As there has been a flurry of postings about re-proofing guns, I thought I should give a heads-up on a rather worrying development at the UK proof houses.
Lately there had been rumours of guns 'unexpectedly' failing proof including some from our most illustrious makers which I doubt is a common occurrence!
Although there have been tales of actions failing, it seems that the majority of these failures have been caused by barrels bulging just behind the chokes. The choke constrictions in these cases have apparently all been in excess of a UK 1/2 or 0.020" and all instances have been with 12b guns, smaller bores seem unaffected.
After several 'unexpected' failures, one barrel specialist asked for a formal investigation of the proof loads that were being used as it is alleged that the start of these problems coincided with a change in the sourcing of the loads used by both Proof Houses. The subsequent reply from the Proof House confirmed that they had tested their proof loads and had found no problems with them.
I have heard it suggested that as they test pressure only at 1" and 6" from the breech face, they are most likely looking in the wrong place but not being a ballistic expert I do not know if this hangs together.
I would stress that I have not been a victim of this problem, in fact I have never had a gun fail proof 'unexpectedly', maybe because I seldom work on guns with heavy choke, and I am sure that the proof houses are working hard to discover if there really is a problem. However, I feel that now is perhaps not the best time to be considering a re-proof of your pride and joy! Best to wait until this has all been sorted out.
Toby,
Are we talking London Proof, Birmingham Proof or Both?
Peter,
I am told both, I'm afraid. Apparently the proof cartridges are being loaded by the Birmingham House for both London & Birmingham.
Toby
Odd place for failures. Pressure is significantly reduced that far down the barrel.
Don't worry Mr. Barclay in America we use Remington Nitromags long string and car tire from behind thick oak trees.
A good reason for more open chokes?
Odd! The sort of thing that you would expect from using steel shot and tight chokes. Lagopus.....
Lagopus, I couldn't possibly comment!
However, someone did suggest examining the cases of proof cartridges with a magnet!
Other suggestion is a highly progressive powder: fine at 1" and 6" but pressure still growing all the way to the choke.
What do I know, I'm only a rank amateur.
So is it a fair assessment that right after abuse and neglect the greatest danger to old doubles are the British proofing houses?
Jim
Again, I couldn't possibly comment!
A similar problem occurred a year and a half ago. I tried to get answers and was shamelessly stonewalled.
A similar problem occurred a year and a half ago. I tried to get answers and was shamelessly stonewalled.
Dig,
Thanks for posting that. I had thought I remembered a thread along those lines.
Pete
Dig,
18 months ago you were a highly respected but relatively powerless cog in the UK gunmaking machine. I wasn't even highly respected and am no better placed now! Now that you are a man of prestige and power, try knocking again, it might produce some results this time!
Seriously, there are some significant people out there who are being driven to do some awkward re-designs to make sure that this is not going to happen to their new guns. There are also some lesser known but equally heavy weight individuals asking some very searching questions and not getting the answers they need to steady their hands! However, some feedback that I have received from one is that individuals within the proof houses are very concerned albeit reluctant to shoulder any responsibility at this stage.
On the case and NEVER been Politically correct!!!!
You may not like what you hear but it will be what I hear or find out.
Please do not confuse me with HomelessJoe.
Is this problem occurring with new guns, re-proofed vintage guns or both?
Trying to find out the facts. Historically the Proof Houses have always been very diplomatic and guarded with making public statements, and perhaps rightly so. If we need to know, they invariably publish a pamphlet or issue a statement.
As far as I can ascertain there have been a relatively small number of incidences to date.
When you consider the number of guns proofed and re-proofed per annum the failures are indeed very small in numbers. It is very early days as yet but it is my belief that it may well be a problem associated with barrel boring, choke profile or metallurgy. Safe to say that it is my belief that any reasonably sound gun with a minimum (less than modified)of choke constriction should (will?) pass proofing.
Just got a pair of damascus barrels back from London Ptoof House - guess what? Bulged just behind the very light chokes.
Is the proofhouse using steel shot now? I do not think so, but something has changed.
The proof houses use the old two rule system when things go wrong.you know how it goes.
1 the proof house is always right ,no matter what.
2 see rule one.
Imagine if this were applied in the automotive industry!
"We are going to test your engines to see if they blow up when revved too hard. But We won't tell you how hard, we'll just let you know if they blew up while we were doing our thing".... and no, you can't opt out or go elsewhere.
Dig,
What you describe actually did used to happen in Motor racing, especially when a driver was having an identity crisis he would disappear around the back of the circuit and deliberately detonate a perfectly good engine. That was until engine management and telemetry became common.
Perhaps the Proof houses need to check pressures nearer the muzzle in light of these current problems.
One thing is for sure these guns that are failing are not the weakest barrels available and have not suddenly all become necessary to be proofed at the same timescale. So we have to question, The test procedure, the test components, the test operatives. Something is definately wrong and IF these valuable artifacts are being ruined by incompetence then recompense should be sought. We both know that will never happen but I am sure the Guardians should be made aware of our concerns.
We are short on facts here, but my money is on shot balling or bridging. I can't imagine a powder able to develop barrel bulging pressure at the chokes without chamber damage. Bulging right in front of the chokes sounds like a gas hammer caused by some event, like balling of bridging, that occurs as the shot encounters the choke constriction and is somehow limited in its ability to flow like a fluid.
Dig, I am really sorry to hear of the proof failure. Any chance this is just coincidence or was it a sound barrel?
I have spoken to others about this matter in the last day or two and it would appear that Birmingham have not been suffering the same rash of failures as London and neither were they aware of London's problems.
Another significant member of the gunmaking community smiled ruefully and commented that nothing much has changed. What he was apparently referring to was the history of a lack of communication and some fairly childish one-upmanship over the centuries between our two august institutions.
I agree with Don.
Barrels that are simply back for a reproof should not exhibit this.
I can not imagine a powder or charge common to small arms that would still be building pressure 26+ inches from the chamber. The only thing that comes to mind would be a howitzer.
We have been instrumenting barrels for nearly 120 years. We know full well how things behave. Too much black powder and it gets blown out unburned. Too much smokeless or too fast a burn rate and you rupture the chamber.
Are they testing with some alternative (none lead) shot in an attempt to lower the over airborne lead at the proof house?
Pete
Reading the rules of proof introduction leaves us in no doubt that oneupmanship has existed for centuries. But this childish behaviour does not help Diggory and others who suffer a loss whilst entrusting valuables to 'experts'.
Don & PeteM thank you for your input and observations, as I have said, there will be a logical explanation and then someone will say "Who'd have thought that". The sooner they find out the better for everyone.
I can't of course speak for every gun ever built, but all that I have ever checked have had a slight increase in wall thickness as the choke was approached. Thus I have never found the thinnest point of the bbl wall to be at the juncture of the bore to the choke cone, but a few inches back. This would definitely seem to negate it being a simple change of powder.
Whatever the ultimate cause it surely seems the shot charge is being "Checked" by the choke & thus having the effect of an obstruction. This would account for the "Bulge" behind the chokes as the check would occur on the front of the shot column hitting the choke.
They haven't started proofing with a bore size ball have they??
Do they use shot when they proof a gun?
Thanks
OWD
Did some probing today. I'll let you know what kind of responses come back on this. This latest glitch cost me £3000 this week!
I am sorry for your loss. Has all the rash of failures been in the London proof house or at both? Those in the trades must be dreading proofing like a bomb disposal expert with two sprained thumbs. Hope the problem is figured out soon or the proof house in question should be avoided like the plague.
I'd suggest making sure nothing stupid is happening like something being stuck down the muzzle/run through the bore such that occasionally a bit is left to act as an obstruction.
Second,I'd make sure thate is no wad issue that could contribute to shot balling.
Third, I'd look for any coating on the shot that could contribute to said shot not flowing and/or having an unusually high friction coefficient for surface to surface contact.
Forth, I'd check shot size inuse and make sure it is #6 or smaller as larger shot is more prone to bridging.
Last, if two, or more, proof loads are being fired, I'd check for shell bases coming loose and lodging in the choke section.
If one of those doesn't get it, I'll have to think some more.
Rocketman,
I think you have covered most of the bases there!
You can lead a horse to water, but you can't make it drink!
I am sure in the fullness of time this issue will be resolved. Will we ever be told the cause?
I doubt it.
In the procedure, there appears to be only one variable since this issue arose, perhaps they should look hard and long there.
Dig, This problem first surfaced on this forum in 2008 [see crossed chissels post 22-04-08.] At That time we were awaiting your respose to the many posts relating to this same issue.Now almost 3 years later you report an expensive failure on one of your own guns. The proof authorites have had adequate time to determine the root cause of these failures. I would have thought by now that the British gun trade would be demanding answers from the proof authorities.Comments please?
I can't see the English proof house being at fault....I'm sure this wasn't their first rodeo.
I'd be interested in hearing the wall thicknesses where the blow is occurring....sounds like it could be too much honing.
HomelessiOe,I did not intend to imply that the Proof houses are at fault.It is not unreasonable to expect that the Proof houses would seek to absolve them selves from responsibility for failures due to inappropriate test proceedures.This issue begs a response from the London and Birmingham Proof Masters and the Guardians of proof.[Majority of the later being members of the gun trade.]
If there was a defect in any gun that failed at proof; dimensional,material or in the manufacturing process, the Proof house did its job in protecting the end user from an unsafe weapon.
I think we would all rest easier with the knowledge that the Proof Houses have been absolved from any responsibility in the failures reported.
You get that close to the muzzle, wall thickness should be pretty much academic. Were that not the case, ported barrels would be blowing at the muzzle, right and left.
I think we have rightly honed in on the questions. Now, we need to hear if any of the jabs have drawn a response from either Proof House...
Roy Hebbes,
I cannot find the crossed chisels post dated 22-04-08.If my memory serves me correctly the earlier failures were different to these.Please advise /enlighten.
Thanks Birdog,
Re-read the lot, it doesn't make very good reading.
Unfortunately I have never seen an official statement, and it seemed to have died a natural death until recently of course.
I thought OWD's question really interesting, because truth be told, I NEVER thought about/read about/encountered shot being used in proofing a shotgun.
Rocketman, in a way, answered this question by mentioning the use of shot in the fouth point of his "Proofhouse Treatise".
Now, of course, thinking of proof marks on my OWN guns, for God's sake, I feel the fool; 1 oz, 1 1/8 oz etc. My eyes always went for the pressure and shell size. How in the world did I think they arrived at the amount of shot for the gun to be limited to?
So now I must add my voice to the masses and chime in, what size shot do they use and is it only one size; Is there a correlation to bore size, i.e. 10 bore gets size X shot, 12 bore gets size Y shot, etc.?
I've wiped the scraps of ignorance from my eyes and I now see a door blown off its hinges.
Thanks to Roy Hebbes's encyclopeadic memory & knowledge and Birdog's help I have been able to re-live this nightmare. It's funny how things tend to be forgotten and heal up if we don't prod the wound isn't it?
Diggory, I think it would be beneficial if you as an aggrieved party were to make an official enquiry about these failures, rather than us carrying on speculating.
You did say that you would get to the bottom of it two years ago, but like me I guess because it 'went away' we forgot about it.
I do have problems with reconciling myself with why we should subject our pride & joy to two rounds of stress just to appease the common market? Which as far as Britain is concerned, nothing good as come out of it apart from the road out.
Two years ago I was told by the Birmingham Proof House that they would make an announcement when they were ready. None was forthcoming.
The declined to answer any specific questions about the incidents and procedures then of concern.
The London Proof House likewise declined to shed any real light except to say that they now get their proof loads from Birmingham.
Richard Purdey commented on my "scurrilous website comments about the Proof House" when I went there for lunch as a guest. I replied "When you stop blowing things up, I'll stop writing about it". He said "We are in the business of blowing things up".
Don't expect to get any answers from either proof house other than what they decide they want to tell you.
Regarding prof failure, the response is simply that the gun was tested and it failed proof. End of discussion.
The quality of stamping also seems to have deteriorated. Double stamps, stamps in places where it results in damage to the action etc are sadly all too common thesedays.
I have a comment to make that although I may be a little off topic, I think bears some thought regarding bulging of barrels near the muzzle. A few years ago I inspected an Italian (less common maker) 410 over/under that had about 47 thou of choke in one barrel---about double the normal full choke constriction ---my bore gauge would not fit into the muzzle! Although it bore Italian proof, I had a safety concern---I also had a concern how it would pattern. I declined to purchase it.
Now, of course, thinking of proof marks on my OWN guns, for God's sake, I feel the fool; 1 oz, 1 1/8 oz etc. My eyes always went for the pressure and shell size. How in the world did I think they arrived at the amount of shot for the gun to be limited to?
So now I must add my voice to the masses and chime in, what size shot do they use and is it only one size; Is there a correlation to bore size, i.e. 10 bore gets size X shot, 12 bore gets size Y shot, etc.?
I've wiped the scraps of ignorance from my eyes and I now see a door blown off its hinges.
I think it's based on gun and barrel weight.
It appears as though this problem has gone away as fast as it started.
The Proof Houses are not aware of any problem!
Perhaps that is why they didn't comment two years ago?
Bottom line....you send those thin barreled old war horses in for a torture test expect a few not to make it home.
jOe,
Unfortunately, and worryingly new guns with ample barrel thickness are bulging also.
But why would you subject a barrel to a double dose of torture when once was always good enough? Plus I can't find it in the 2006 rules of proof as to why we have to double test?
Another thing, why have they changed from commercially provided ammunition to loading their own? Why did a commercial cartridge manufacturer decline to load for them?
I do not think it is unreasonable to ask for answers, unfortunately they are not forthcoming.
Over to you Diggory.
In the past has either house had a suit filed against them for failure of a proofed gun causing injury? Perhaps they are doubling loads up to lessen the chance of such an occurrence. Sort of like Smith & Wesson putting internal locks on guns, perhaps they are becoming scared of the lawyers. Perhaps their insurer is demanding it.
Cheaper to get sued when a good gun gets blown up than when a good hand gets blown off.
Apparently several new AYAs recently failed at the chokes. This is just more of what has been reported to me verbally so 'Allegedly' should be added wherever appropriate. The Trade is rife with gossip about unusual proof failures at the muzzle ends of guns that pass visual inspection and have been properly prepared by top gunsmiths with strong expectations of them passing.
Something is wrong.
Small Bore,
Reference Burrard,The Modern Shotgun Volume 3,The Gun and Cartridge, pages 375-378,[deals with obstructions and bulges near the muzzle.]
Quote:"Ring bulges near the muzzle are usually caused by some form of obstruction in the bore.They normally occur between .75 and 1.25 inches from the location of the obstruction. Position of the choke [acting as a restriction] and the wave pressure generated by the charge fired are also important factors in the location and forming of ring bulges."
A pertinent question for the Proof House:might well be;
"Dose the Proof house test proceedure require the barrels to be cleaned and viewed prior to and after the first proof test; so as to ensure that there are no fragments of the first charge remaining and/or permanent deformation of in the barrel, prior to the second proof test? If this proceedure is not in place[and strictly adhered] to,the possibility of fragments of the first charge remaining in the barrel exists and could result in formation of a ring bulges.
You have a point there, Roy. From what little I know, bulging behind the chokes would seem to support an obstruction. Or it's almost as if they were using steel shot.....
Mike
The choke section should never act as a restriction to properly functioning shot pellets. Rather, it is a constriction which the shot will flow through with decreasing pressure and increasing velocity. I think the disproportinate number of fowlers, as compared to gameguns, with bulges immediately behind the choke section is evidence of the larger shot usually used for fowling being more succeptible to bridging. The even brief existance of a bridge could slow the shot/wad sufficiently to create a gas hammer behind the wad. Sounds like the same thing could be happening here.
Is there an inspection that would catch a fragment, say base wad, from the first firing? Are the hulls tracable to the gun fired in?
Dig, were both barrels bulged?
I seem to recall reading in W W Greener that when choke boring was first introduced there was still a good many guns being made with low quality bbls consisting mostly of iron with very low steel content. Seems these soft bbls could not stand up to choking without bulging.
Personally I am not convinced that when that charge comes hurtling down the bore that there is not a "Check" applied to it as it hits the choke. Normally it is not so severe as to cause any problem, "But" if the bbl is too weak, too thin, too soft etc, then things can change.
In my case and the case of a Westley that came to my attention, both tubes bulged.
Too many guns are bulging in the same place for an obstruction of wadding etc to be the answer.
All the points about occasional bulges in the field are valid but in the recent cases, too much repetition is evident for it to be dismissed as sloppy cleaning or a weak tube. A lot of guns are failing where they would previously have passed. My own observations lead me to suspect steel loads are being used but I have no evidence to support this other than the reports of the number and types of failures.
miller,
What you mentioned about the choke acting as a sort of "check" seems to the logical mind to be so. However, we have been told that small shot acts like a liquid, and that as it enters the choke it actually speeds up, being subject to the venturi effect. We see other applications of the venturi effect around us, carburetors, cooling towers at nuclear reactors, etc.
I, however, am not convinced that a load of shot acts the same as a moisture laden gas, and will continue to believe that great stresses occur when the shot enters the choke constriction area. The greater the constriction the greater the stresses, I believe.
What I would find interesting is how the bulged barrels in question were choked.
Stan
Stan
A choke barrel should not fail proof because it is choked. We are missing the point here.
Dig, this whole thing with bulges and proof failures is very troubling to me. I'm planning on sending a set of barrels from a high grade Lefever for Teague liners. I certainly wouldn't want a set of unreplaceable barrels destroyed because of some stupidity on the part of the proof house. Would you suggest holding off on the lining until this issue is resolved?
Doug
I understand that Mr. Teague doesn't line barrels anymore.
Doug
I understand that Mr. Teague doesn't line barrels anymore.
John, Would it be more proper to say that Jon Connor lines barrels or is no one doing that service now???
Doug
I don't know who did Nigel Teague's lining for him but I know that Nigel does not offer that servise anymore as it was not to successfull. So he withdrew his name from it.
Sorry for going off topic.
Doug if I can help in anyway email me.
Doug,
I would certainly hold fire as Toby said until this is resolved.
Maybe SKB can enlighten you on the liner situation?
miller,
What you mentioned about the choke acting as a sort of "check" seems to the logical mind to be so. However, we have been told that small shot acts like a liquid, and that as it enters the choke it actually speeds up, being subject to the venturi effect. We see other applications of the venturi effect around us, carburetors, cooling towers at nuclear reactors, why airplanes and hydrofoils fly, etc.
I, however, am not convinced that a load of shot acts the same as a moisture laden gas, and will continue to believe that great stresses occur when the shot enters the choke constriction area. Would you not describe the passage of shot through the reloader as flow? Probably, shot doesn't act exactly as a fluid, but it certainly does so in many ways. If the choke is not responsible for a venturi effect reduction of pressure within the shot column, then to what do you ascribe choke effect?
The greater the constriction the greater the stresses, I believe. This line of logic should lead you to believe that the sharper the choke taper the higher the stress. However, choke taper angle is not much of a concern in choke performance. Rather, it is the total constriction. In a very sharply tapered choke, the shot charge could be aware of the total constriction. However, in a shallow taper, the shot charge could all be contained within the choke section and have no idea of the final diameter.
What I would find interesting is how the bulged barrels in question were choked.
Stan
Stan
Don, If there is a reduction in pressure within the shot column it is just a physical side effect of the forced lengthening of the shot column, emphasis on "forced", because all of it simply cannot get through the constricted area in the same length that it was before entering it. Lower pressure within the shot column does not assume no stress is transmitted to the barrel at the choke area. If indeed there is a lowering of the pressure within that shot column it comes at the expense of great outward force which is the result of the column being forcibly lengthened. What I meant was that I do not believe that shot necessarily SPEEDS UP while passing through the constricted area (choke, venturi). This is what I was taught in physics was meant by "venturi effect", the acceleration of the gas or liquid. I am not entirely dogmatic on this point, however, as I cannot prove it either way. If it has been proven that shot accelerates in a choke, I stand corrrected on that point. Sure, shots flows, but not the same as a gas or liquid, IMO. The shot flowing through my reloader is not under several thousand psi, either. Of course no outward pressure is being exerted as the shot enters the drop tube on a reloader, it is only being acted upon by gravity. It isn't hitting a constriction at 1250 feet per second.
The length of choke taper has been debated and argued for many decades. Many different makers had their beliefs/ideas about this. I have my opinions as well, and opinions are all I claim them to be, not fact. However, if the sharpness of taper has no effect on choke performance, why not just try cutting a .040" X-full choke with a taper length of only .040"? This is an extreme example, just to make a point, because hopefully you don't believe that the stresses on the barrel steel in the radical taper would not be greater than it would if the taper took place over a distance of 3/4 inch, or more.
I did not make my point clearly enough in the earlier post, when I said that I would be interested to know what the constrictions were in the bulged barrels, that I was relating it to the earlier thoughts that possibly the proof houses had begun using steel shot proof loads. I certainly don't think that tight choke alone should cause a sound barrel to fail proof with a lead shot proof load. But you don't really believe that all shot, even that of very hard material, flows through chokes without causing stresses to the choke area, do you? Even steel? I think you know how risky it is to shoot steel shot loads through very tight chokes. I have seen any number of ruined chokes and barrels, at a friend's choke tube business, that were ruined by using steel or harder non-toxics through very tight chokes. The venturi effect may have eventually lowered pressures in those shot columns, but it was at the expense of a barrel and a choke tube.
Stan
WOW! When did Nigel Teague stop the lining service? I've seen plenty of barrels lined by nim...was it this year he stopped?
B
Don't forget its gun proof ammo, muzzle pressure is pretty much high and any minor changes in proof ammo loading could be fatal. For instance lead shot hardness of every pellet and its size.
In 70-th of last cent. Germans began to use parabolic full chokes in Merkel o/u's gun as it was used in Russian sporting guns such as MC-8, these chokes gave extremely tight patterns when small shot numbers were used. The result was ring bulges on most Merkels, when large shot numbers were used, because MC-8 was heavy gun with massive barrels, when most of Merkels were light weight guns.
If they are using a nontox shot or steel to load proof loads then they have altered the test beyond any reasonable test for these old doubles to pass. Why on Earth would anyone decide to test with steel? Has the proof house suffered a serious drop in IQ?
The entire reason for the test is to assure guns pass a reasonable standard test. For years we have deemed a gun safe to shoot, with the correct loads, if it passed proof and was in proof. Never considered shoot loads that by their very nature would cause major damage to my gun. And I never thought a Proof house would do it without major disclosure and fair warning. Shoot steel loads in a tight choked gun and you will soon have major barrel damage unless you can repeal the laws of physics. This is either unthinkable or unbelievable and I am not doubting the charge or the messenger.
Doug,
Nigel Teague sold the rights to the process to Jon Corner. Jon developed the process for Nigel originally and did the work for him under contract. Nigel decided to focus on his choke tube business and the rights and name were purchased by Jon. We have had very good success with the process and are currently taking orders. More information can be found on my website.
This answer is intended to be in the spirit of debate - nothing personal or derogatory intended.Don, If there is a reduction in pressure within the shot column it is just a physical side effect of the forced lengthening of the shot column (disagree as the lengthening of the shot column comes with increasing velocity which requires reduceing pressure), emphasis on "forced", because all of it simply cannot get through the constricted area in the same length that it was before entering it (agree, but I believe the shot must obey fluid flow laws and acts mostly as a fluid in a venturi). Lower pressure within the shot column does not assume no stress is transmitted to the barrel at the choke area (Stress on the choke area must be the hoop stress due to pressure within the shot column and the following gas column. I do not believe the shot is transmitting momentum to the choke walls.). If indeed there is a lowering of the pressure within that shot column it comes at the expense of great outward force which is the result of the column being forcibly lengthened (Disagree. The lowering of the pressure within the shot column is in exchange for the shot speeding up to maintain mass flow rate.). What I meant was that I do not believe that shot necessarily SPEEDS UP while passing through the constricted area (choke, venturi) [Yep, this is well established by Remington data from the '30's - one fps per 0.001" constrictionis a fair rule of thumb.]. This is what I was taught in physics was meant by "venturi effect", the acceleration of the gas or liquid [Venturi effect is acceleration of the fluid in exchange for reduced pressure. Venturies have been used on airplanes as a sorce of vacuum power for instruments]. I am not entirely dogmatic on this point, however, as I cannot prove it either way. If it has been proven that shot accelerates in a choke, I stand corrrected on that point (Remington has published proof that choke increases shot speed). Sure, shots flows, but not the same as a gas or liquid, IMO. The shot flowing through my reloader is not under several thousand psi, either (Just gravitational pressure of the column). Of course no outward pressure is being exerted as the shot enters the drop tube on a reloader (Disagree. Not a lot, but there is pressure due to the weight of the column due to gravity) , it is only being acted upon by gravity. It isn't hitting a constriction at 1250 feet per second (if it does flow, it doesn't actually "hit" the constrictiion).
The length of choke taper has been debated and argued for many decades. Many different makers had their beliefs/ideas about this. I have my opinions as well, and opinions are all I claim them to be, not fact. However, if the sharpness of taper has no effect on choke performance, why not just try cutting a .040" X-full choke with a taper length of only .040" (Not exactly no effect, but over usual taper lengths, say 1" to 7", no appreciable effect. Very short or highly constricted tapers would get into the sonic speed of the shot, not the sonic speed of air, but of the shot and I don't know what that would be.)? This is an extreme example, just to make a point, because hopefully you don't believe that the stresses on the barrel steel in the radical taper would not be greater than it would if the taper took place over a distance of 3/4 inch, or more (Would depend on some factors I don't know. Remember Greener's experiment with a super thin choke wall.).
I did not make my point clearly enough in the earlier post, when I said that I would be interested to know what the constrictions were in the bulged barrels, that I was relating it to the earlier thoughts that possibly the proof houses had begun using steel shot proof loads. I certainly don't think that tight choke alone should cause a sound barrel to fail proof with a lead shot proof load. But you don't really believe that all shot, even that of very hard material, flows through chokes without causing stresses to the choke area, do you? Even steel? I think you know how risky it is to shoot steel shot loads through very tight chokes. I have seen any number of ruined chokes and barrels, at a friend's choke tube business, that were ruined by using steel or harder non-toxics through very tight chokes. The venturi effect may have eventually lowered pressures in those shot columns, but it was at the expense of a barrel and a choke tube. I think steel shot is more prone to bridging due to larger shot sizes and higher inter-pellet friction of steel on steel. The bulge comes from a gas hammer and scoring can occur as the end pellets skid against the barrel walls. Stan
Stan, come on back with points. You have raised good and logical issues that you should feel comfortable with.
This should be something that testing could clear up. I have a Pressure Trace we can use (straingage), I enviison we'd need a couple barrels screwed together and the ultimate port job might help reduce most of the hoop strain from gas pressure and provide some contrast in the strain values. Straingage two areas: one at the choke cone, the other along the straight bore. Just need a pump, single, or auto with two plain barrels we can wreck.
Rocketman,
Have you conducted, or do you know of any research concerning Young's Modulus of good Damascus barrels? This would be in reference to the elastisity of steel shot passing through the choke constriction and if the Damascus barrel expands and contracts.
I witnessed steel shot, #2's and smaller, being fired in Damsacus guns with no noticable effects. The chokes of one 12 gauge Parker's Damascus barrels were measured .030" and .035" constriction and minimum barrel thickness of .030". I was so amazed at that Damascus "steel shot special" that I bought it.
The story behind the subject Parker is that the owner thought that the chokes were .015" and .020". Only later when he had access to good barrel thickness and choke gauges did he realize his mistake. Of course, he continued shooting that gun. When I bought it about 150 rounds of high quality steel 4's and 2's had gone throught those chokes. As one might guess the stock is cracked from the recoil of those steel loads.
If I could obtain access to the means to accurately measure the barrel's expansion and contraction this gun might be sacrificed to research.
Respectfully,
Mark
Chuck, I'd really like to see you try that but, I would think you should test it without porting, and then port the barrel for testing, even in varying degrees, testing loads in it all along the way. Might learn even more by doing this. I will donate a 12 ga. Rem. 1100 barrel for the testing.
Don, let me chew on this some today while I harrow some firebreaks in the pine plantations. I'll get back to you tonight. Thanks for replying.
Stan
This should be something that testing could clear up. I have a Pressure Trace we can use (straingage), I envison we'd need a couple barrels screwed together and the ultimate port job might help reduce most of the hoop strain from gas pressure and provide some contrast in the strain values. Straingage two areas: one at the choke cone, the other along the straight bore. Just need a pump, single, or auto with two plain barrels we can wreck.
Chuck,
If you are serious email me.
Pete
Don . . . "increasing velocity requires reducing pressure". Are you speaking in general, or only in the specific case of the changes that take place as a shot column passes through the choke? I ask because, while pressure and velocity are not directly related, more often than not an increase in velocity will be accompanied by an increase in pressure. Or at least that's what you see if you look at a reloading manual.
Larry, while pressure and velocity are not directly related, there are more tight connections between these units, than you could think and plz stop to repeat this sh*t every time.
While I understand the rationale to relate this to Bernoulli's principle, I'm skeptical that it would be applicable in this debate.
I'm looking at the stress/strain issue on the choke as more of a single impact event, where the shot is traveling in a direction and then deflected in another. I suspect the point of highest stress will be somewhere along the cone.
Gas dynamics. The gas pressure will be increasing dramatically just behind shot column and wads, if shot column and wads meet obstacle such as full choke for example and slow down.
This should be something that testing could clear up. I have a Pressure Trace we can use (straingage), I enviison we'd need a couple barrels screwed together and the ultimate port job might help reduce most of the hoop strain from gas pressure and provide some contrast in the strain values. Straingage two areas: one at the choke cone, the other along the straight bore. Just need a pump, single, or auto with two plain barrels we can wreck.
Rocketman,
Have you conducted, or do you know of any research concerning Young's Modulus of good Damascus barrels? This would be in reference to the elastisity of steel shot passing through the choke constriction and if the Damascus barrel expands and contracts. Unfortunately, I know of no such data.
If I could obtain access to the means to accurately measure the barrel's expansion and contraction this gun might be sacrificed to research. See above, Chuck's proposal will get the information you/I/we want. Strain gauges are based on the change of electrical resistance with the "stretch" of the barrel.
Respectfully,
Mark
Chuck, I'd really like to see you try that but, I would think you should test it without porting, and then port the barrel for testing, even in varying degrees, testing loads in it all along the way. Might learn even more by doing this. I will donate a 12 ga. Rem. 1100 barrel for the testing.
Maybe we can get a test going. Don, let me chew on this some today while I harrow some firebreaks in the pine plantations. I'll get back to you tonight. Thanks for replying.
Chew away, Stan. This is not a timed event. Stan
I'm willing to machine a couple barrels to screw together. I would hope we could find a tightly choked barrel for this. Sounds like Pete may have something.
I really think porting after something like 18-20" in the first barrel is a good idea to reduce gas pressure as low as possible to negate any effect on the strain measurement, since this debate is about the stress effect of the shot column on the choke.
Don . . . "increasing velocity requires reducing pressure". Are you speaking in general, or only in the specific case of the changes that take place as a shot column passes through the choke? The specific case of a fluid passing through a constriction. I ask because, while pressure and velocity are not directly related, more often than not an increase in velocity will be accompanied by an increase in pressure. Or at least that's what you see if you look at a reloading manual. Good point. However, we need to look at several "pressures." I agree that there is not a general relation between peak breech pressure and MV. However, there is a very direct relationship between average barrel pressure and MV. For example, a fast powder can produce a higher breech pressure and a lower average barrel pressure than a slower powder; this is because the charge of slower powder contains more chemical energy - the retarded burn rate allows a larger charge of slow powder without high breech pressure. By the time the shot reaches the choke, the powder is long since burned out and the choke passage is a typical fluid dynamics event. IMO
While I understand the rationale to relate this to Bernoulli's principle, I'm skeptical that it would be applicable in this debate. The Remington data shows that MV increases with increasing constriction. There is nosource of additional energy. So, how else can we account for this?
I'm looking at the stress/strain issue on the choke as more of a single impact event, where the shot is traveling in a direction and then deflected in another. I believe the pellets act independently as fluid particles and not as a solid mass. I suspect the point of highest stress will be somewhere along the cone. If you are right, it should be exactly at the cone entrance where all pellets would have to change direction.
Don,
do you mean to say that: if the pressure drops in the choke, there will be, effectively, no expansion (no change in strain value) of the barrel at the choke?
Toby,Over the past 2-3 years we have seen many posts reporting abnormal failures of guns during proof testing in the U.K. This is causing consternation on the part of gun owners,in particular those considering sending valuable guns for reproof. The failure of the proof houses to issue a statment on this issue,is in my opinion damaging their otherwise excellent reputation.
Resolution of this issue is very important to the British gun trade and their customer base.If the Proof house and the Gun trade have not already embarked on a joint study to resolve this issue they would in my opinion be well advised to do so.
The University of Aston, in Birmingham, is but a stones throw, from the Birmingham Proof House; surely this highly respected technical University would have the expertise to advise and resolve this matter.
Don,
The wads from some steel/hard non-toxic shot are tapered so that the side petals of the wad are significantly thicker toward the base of the wad than toward the top. Could this positively affect at least the start of the flow of shot under Bernoulli's Principle?
Respectfully,
Mark
Gas dynamics. The gas pressure will be increasing dramatically just behind shot column and wads, if shot column and wads meet obstacle such as full choke for example and slow down.
Don, if "the pellets act independently as fluid particles", as you said earlier, how do we explain the ruptured chokes so prevalent when steel, and especially hevi-shot, is used in conjunction with very tight chokes. We say, "because of bridging", right? Well, how can a substance acting as a fluid be subject to bridging? If all those little balls, acting so independently as fluid particles, are able to bridge, occasionally, to the point that the barrel, in the choke area, is violently ruptured, then I say we cannot use the Bernoulli Principle to predict the flow characteristics and resulting pressures, within and without the shot column.
As I understand it, even the Bernoulli Principle is subject to modification because of the difference in viscosity of the substances being examined. In it's simplest form, Bernoulli's Principle governs an inviscid flow. Where does lead shot fall, as far as viscosity is concerned, and steel shot, and tungsten/iron shot? And, could a number value for viscosity can be assigned to the different types of shot? More questions.
And, again, how does a "liquid" (or a mass acting as a liquid) bridge and burst chokes if there is a reduction in pressure? The gas pressure may have reduced, but the forces acting on the barrel at the burst point certainly have not. I can accept that there can be a reduction in pressure AFTER the shot has passed the taper, and maybe even a velocity increase because of it, but cannot yet accept that the shot exerts no strain on the tapered area of the barrel.
How in the world can we even compare the dynamics of small shot, as it passes through the taper, with that of much larger sized shot? There IS a difference in it's behavior at that point, or there wouldn't be all the burst chokes and barrels due to the larger hard shot, as compared to the smaller.
Still chewin', Stan
Don,
do you mean to say that: if the pressure drops in the choke, there will be, effectively, no expansion (no change in strain value) of the barrel at the choke?
Don,
Unfortunately, my device only has the capability of one input at a time. You could still get statistical information.
That last sentence was a hint... I'm willing to machine all the parts and provide the device, Pete is onboard with supplying the guns. I'm thinking you're the right person with the right credetials for the testing.
Don,
do you mean to say that: if the pressure drops in the choke, there will be, effectively, no expansion (no change in strain value) of the barrel at the choke?
Don,
That is the reason Chuck and I need you to blow up a couple of guns for us!
Roy,
This whole situation is becoming more troublesome with each passing day.
Today I received news of 3 freshly sleeved guns from a highly respected specialist all failing proof with bulges behind the chokes.
Understandably the specialist asked for an investigation and the Proof House has offered to do the subsequent tests using old proof cartridges from a previous supplier. I have an interest in this as I have several guns in the log jam from this situation and I am crossing my fingers that all will be well.
It would appear from this development that the London Proof House has tacitly admitted that there is something amiss with their proof loads although the are admitting nothing verbally.
The problem with what you suggest is that the Proof Houses are very much a self contained, self regulating institution. If they brought in outside help, they would probably see that as an admission that they are not up to the job, something that I doubt they would be prepared to do.
Furthermore, if they had been at fault, they might be at risk of becoming liable for all the damage they are currently causing. Again, not something they are likely to relish.
It would appear that this current difficulty is centered in London, I have heard from 2 sources that Birmingham were unaware of London's problems.
Give me strength!
Toby,As I understand the proof regulations,the U.K. proof houses were established by act of parliment. Surely this means they have a responsibility to report to a parliment. For example, who whould take action if the weapons failing proof were military issue? Is this an avenue worth exploring in order to expedite resolution?
OK. I will do it. I will have be careful that I can work around available time. But, basically, yes, I'll do the testing.
One input is only inconvenient, not problematic. How many strain gauges do you think? Breech pressure, barrel pressure just in front of the choke section, the start of the choke section, and muzzle?
Don,
The wads from some steel/hard non-toxic shot are tapered so that the side petals of the wad are significantly thicker toward the base of the wad than toward the top. Could this positively affect at least the start of the flow of shot under Bernoulli's Principle?
Respectfully,
Mark
I don't think so, as these principles were at work back when shotguns lacked shot protection. The venturi effect is, unfortunately, counter-intuitive to "common sense," which is why it was so long to be discovered.
Don,
I'm not sure how much you want to expand the research. But I'm leaving that up to you.
One nagging question I have and probably many others is the comparision of steel vs lead on the choke area stress. Then further comparisons of smaller vs larger shot size in both lead and steel. All testing should probably be done with like loadings from same mfrs when doing the shot size comparisons, of course.
I also have a chronograph if you don't have one.
If I might add a little to the thoughts. In one of the appendices to The Modern shotgun bu Burrard he reported on some tests which had been conducted in England. A heavy pendulum gun qa fitted to record max pressure, velocity & recoil. Two bbl extensions were very carefully fitted & lapped to identical diameters, one cylinder bore & one full choke. Loads of several varieties of powder were tested from the heavier of the bulk smokeless down through a fairly light dense powder & If my memory is correct I believe black as well.
Bottom line was that though small, statistically significant readings showed the full choke to give higher velocity & lower Recoil readings. Velocity was of course the "Observed" velocity over 20yds. Load in all cases was the normal 1 1/16oz with 3 dram measure or equivelent depending upon powder. The conclusion drawn at the time was that the choke "Checked" the velocity but the shot remained closer together as the exited the muzzle
& drag was less for a short distance allowing them to more than regain the loss.
Now, if we can take it the Remington tests recorded velocities close enough to the muzzle to eliminate the possibility of the results being skewed by outside influence, then obviously their conclusion, though reasonable, was not factual.
But, Something caused the lowered recoil & it wasn't the "Speeding Up" of the shot. So what's left. Note the comparsions are strictly between the F choke & Cyl for Each load, everything else being identical. Maybe, just Maybe we need to look to the wadding. Could the wadding have been checked enough to slow the ejection of the gases just enough to give the lowered recoil??
I am going to go out on a limb & "Predict" you will find a point of a slight pressure spike when you run your tests. You may have to move the strain gage around a few times to find the right place, but it'll be there. Normally this will not be enough of a spike to bulge a bbl as the check is slight, & the load is moving so rapidly at the time it takes a bit for the gases to "Catch up". I do seem to recall seeing high speed pics of the charge as it leaves the muzzle & the wad was snugger against the shot from a cylinder than from a full choke, which indicates the wad was delayed by the choke.
From further back in this thread I recall it being mentioned the proof house had quit using shells supplied by the trade & started loading their own. Maybe its not the shot at all, maybe they are using stiffer & heavier wads & these are making enough difference to create the bulge in sme cases.
OK. I will do it. I will have be careful that I can work around available time. But, basically, yes, I'll do the testing.
Thank you Don. I leave it to you and Chuck to design for best possible data.
Pete
A couple of years ago the Birmingham Proof House were having an abnormally high percentage of failures in 20 bores. Not choke damage but just burst barrels and cracked actions as would be expected from proof overloads. I don't know if Smallbore has any knowledge of this. I submitted a 20 bore with damascus barrels at around that time. The barrels were o.k. but the action was bent like a banana. Lagopus.....
Too much black powder and it gets blown out unburned.
Pete
That might hold true with a muzzle loader over loaded by a small amount....but don't think you can't reek havoc on a cartridge gun with an over load of black powder.
It is quite true that Black powder is quite capable of building excess pressure. However, the vast majority of cartridges designed for black were designed for all the powder the case would hold up to the bullets base, usually compressed somewhat. Normally there simply is no place to put an overload. In fact even with old style baloon head cases most find it difficult to get the amount the cartridge's nomenclature would indicate. Did you ever try to drop 70 grains of black into a .45-70 case & then try to seat a bullet for instance??
My 1889 Lefever Arms Co catalog recommends for a 12ga gun of 7-8lbs wt up to 3½ drams-1¼ oz. Then for 12ga 8-9lb guns up to 4½ drams-1¼ oz. You'll have a hard time getting any more than that 3½-¼ load into a 2 5/8" shell, with the heavier loads requiring long hulls. Other than muzzle loaders its generally hard to over load a black powder gun, because their shells were built around the correct charge & there's just no room left for extra.
I would not however recommend taking an old gun & loading these charges using 4FG priming powder, that might well lead to some fantastic pressures. In fact I would personally not recommend loading anything heavier than a 3-1 1/8 load in a 12ga with 3FG powder. Anything over this I would switch up to 2F or for the very heaviest ones in the long hulls even up to 1FG.
I do agree, Black Powder is capable of building considerable pressure.
Before I knew better I wrecked a 12ga. Gibbs Jones under lever with 1 & 1/4oz of shot and 4 & 1/2 drams of FF Goex in just two shots....like some I was told too much black and it would just blow out the barrel.
Joe;
I don't buy that "Just Blowing out the Barrell" either. I am though somewhat surprised that load wrecked the Gibbs. In what way did it wreck it?
Bad off face in two shots.
Don,
do you mean to say that: if the pressure drops in the choke, there will be, effectively, no expansion (no change in strain value) of the barrel at the choke?
Don,
That is the reason Chuck and I need you to blow up a couple of guns for us!
Pete & Chuck.
I don't envision blowing up any guns- yours, mine, ours, or theirs!! We need a very simple single barreled gun where we can have cyl and full choke. I'm imagining a a choke section like a very long extended choke tube. We need to provide a means to pressure calibrate strain gauges at all locations. Chuck, my chronois oldand hasn't seen the light of day in years (I've had easy access to betterinthe recent past, but not now), so, I'll check mine out and let you know if I need yours.
I'm thinking a 10 shot series for each strain gauge with a common factory load. Six gauge locations on two chokes would be 120 shots. I'll provide ammo. Also, I'll capture patterns from each choke and we can see if Andrew Jones will run statistics on them. Chuck, what sort of computer will your pressure rig need? Pete, what do you have in mind for a gun?
Don,
a simple laptop of windows OS, either XP, Vista, or Win 7 (32 bit only). The software can be downloaded here.
http://www.shootingsoftware.com/ptsupport.htm
It has all gone quiet over here. Have people stopped sending guns to London for Proof?
Come on Diggory, what is the update?
I think they are now sending them to Rocketman and Chucks proof house....
I spent all last Thursday at the Birmingham Proof House for a series of articles I'll be working on. I spent some time going through the steps of the proofing process with the proof master and his superintendent, and also got a look at their ballistics lab.
That does not mean I am able to offer real answers to problems of proof reported here, or their cause, which seem to be mostly coming out of London.
I understand that in the past the London house may have obtained at least some of its proof loads from various sources, so in theory some could have been too weak, thus allowing guns that might have failed to otherwise pass, and conversely some could have potentially been too strong, thus wrecking sound guns. Today the Birmingham house is supplying the proof loads to both houses.
I can report a few impressions: Birmingham was just accredited to ISO standards in late 2010, which means they are working to very strict international standards of control. I had a look at the lab, where shotgun proof ammunition was being loaded as I observed (this wasn't done for my benefit, I just arrived in mid-process). Proof loads are made in small batches, with each load's shot and powder charge individually weighed and, if necessary, corrected with additions or subtractions of powder & shot to meet the load's specifications. Batches are given lot numbers and are kept in temperature-controlled conditions, both for storage and just prior to proof firing. There has been lots of modern ballistics measuring equipment added since my last visit a decade ago. This is not a seat-of-the-pants operation.
Since 2006 two proof loads are fired per barrel, which is done to meet CIP standards. One could surmise that in some cases two loads are too much for some old guns but I do not offer the professional expertise of a ballistician.
My overall impression is that the Birmingham house is working, as I said, to very strict standards and is staffed by a team of experienced, conscientious technicians. I realize that this is not a full and satisfactory answer to many questions raised here but I do not think negligence is the root of reported problems.
I'll have more on CIP proof and the process of proof in coming issues of SSM.
Vic,
Just 1 question. Are they using lead?
Pete
Pete:
According to 2006 CIP Rules, which both proof houses work to, "Standard" as well as "Superior" (magnum) proof call for lead shot.
"Steel" proof calls for lead-free shot of a certain hardness (steel).
It would be hard to imagine steel being substituted for lead, esp on a chronic basis.
Vic,
Thanks.
That was not my thought. I wondered if they may have tried a non-toxic substitute.
Your post clears that up.
Pete
It is very disturbing that to date the London Proof House is still continuing to destroy NEW guns.
It reminds me of when we started to do smoke emission testing of Oil Engines (Diesel) the original test consisted of revving the engine and maintaining high rpm whilst the smoke test was carried out.This resulted in numerous destroyed engines until the British Government Ministry of Transport took the decision to discontinue this method of testing.
Perhaps before too long a resolution will be found and the lunatics will be back in the asylum.
We can but live in hope, because common sense does not seem to be prevailing.
Just as a matter of interest hpw many people who have discussed this have actualy had a gun fail proof at London ? Apart from Smallbore,who should know that guns are sumitted at owners risk and who as an R F D should have factored that risk in to any submission. So how many of you have had a failier???
Great logic gunman. Everyone knows proof is a risk, as it s a test. When significant numbers of apparently sound barrels start failing in a manner not usually observed, even RFDs have a good reason to wonder if all is not right.
Vic, did you notice what size shot was in use? Any idea about its hardness?
So thats only one person on this forum thats had a failier then, as my original question asked. Any others? You talk of significant numbers .What do you mean by that? 10% 20% ?How many guns have you submitted in the last year and how many have failed?
As a PS I am like most people In the British gun trade concerned with the problem and agree whole heartedly that a solution needs to be found.
But , this is our problem and endless discusion on an American web site is not the answer. Discussion within the British Trade and investigation by the Proof Houses is what is needed . If indeed London is "blowing up barrels " then use Birmingham as they do not seem to have the same problem.
I say again this is a British problem ,washing our dirty linen in public is not going to help.
Gunman,
Unfortunately, as you well know there is no forum for discussion with the proof house.
I have always tried to answer anyone's concerns openly and truthfully with the details that I have at my disposal.
I have sent both you & Dig pm's expressing my concern at the way that this situation is being handled, or not as it may seem.
Thats my point . This is not the way to deal with a problem . We have the Gaudians in Birmingham ,the Gunmakers in London and the Gun Trade Assosiation . It is down to them/us the Uk gun trade to sort it out .Not and I mean no disrespect, to any one else.
Rocketman:
Can't answer your question accurately at the moment.
Traditional lead proof loads were English No. 6s (per Appendix II, 1954 Rules)
2006 Rules do specify a Vickers Hardness index for loads for proof for "lead-free shot" (Steel)
Today the Birmingham house is supplying the proof loads to both houses.
The clue at last....Birmingham.
Could the London, Birmingham proof house feuds be back ?
Joe,
With all due respect the feuds were possibly an overstatement, embellished by two hundred years of posts on doublegunshop.com.
Certainly not a current day problem by any means, we all have to observe the rules.
Maybe it is time to bow out gracefully.
Rocketman:- Yes for standard proof we use No6 Lead pellets.
Bowing out now just adds fuel to the Proof House feud theory....you think it could be an inside job by a saboteur ?
Salopian and Small Bore.
How many guns have you submitted to proof in the last year?? How many have failed?? Let us have some numbers. Have you contacted the GTA about this?? Have you put it on the agenda for the GTA. AGM in May??
I have submitted many new guns, used guns and sleeved guns to both proof houses in the last year with 100% pass rate and I don't know anyone in the trade that is having a problem with their guns failing.
Salopian are you in the gun trade?? If so send me a PM and tell me who you are.
I have also had 100% pass rates until this recent failure. However, when the word comes through from friends in the trade to be aware that guns are suddenly failing with bulges behind the chokes - and then exactly that happens to your next submitted gun, it is natural to ask the question "Why now?"
Big deal 1 gun that fails proof and you make all this fuss. Just send it out for sleeving and forget it.
I've also heard from friends in trade that they have heard of more problems recently. This isn't just a blip...something appears to have changed in the processs..
t
You wouldn't have a vested interest in giving that answer would you John? besides, if my gun were the only one, I would not be as concerned that there was a particular issue. Numerous reports such as there are raises questions. I'm just asking questions.
The "don't wash our dirty linen in public" approach is typical of the gun trade. Keep it quiet, don't explain anything, don't take responsibility and wait for the problem to go away. Until next time.
Stop sending the old war horses in...
I do not think that this thread is now going anywhere.
Should the problem that does exist be resolved, I will update you all.
Until that time I will refrain from posting.
For John Foster to make such a ridiculous statement as he has obviously shows that he could not care less about valuable guns being damaged, sometimes beyond repair.
I find that attitude very poor.
The original poster only started this thread to make people aware of possible problems and many of us have only posted to share knowledge and experiences.
A good number of folks in the US do send their British guns back for re-proof. While I am not personally in that category, I do applaud those who have brought this to our attention.
How could I have a vested interest?? You have 1 gun failed proof. It is proved unsafe to shoot that is what the proof house is for. They have saved some one from blowing their hands or face off. The gun now needs to be repaired and reproofed. So have it sleeved.
All the other guns that have failed proof are just hear say. I haven't heared of any failing and there are few people that put more guns into proof than me.
Salopain, You have it wrong, a gun that requires reproof is NOT a valuble gun it is a potential sleever and it is valued accordingly. You still have not sent me a PM with your ID and gun trade qualifications.
As it is The Gun Trade Asosiation AGM in May ,to which I assume that all the British correspondents are members. Can I ask has the GTA been askeked to mediate on your behalf? Has the GTA been aproched and this matter put on the agenda for disscusion? If not why not.
Gunman, That's what I asked but these 5 minute wonders who think they know about the gun trade will not answer my questions. They seem to be all blow and no go. If we submit good quality workmanship to the proof house it will pass. Only the junk fails and so it should.
As a PS I am like most people In the British gun trade concerned with the problem and agree whole heartedly that a solution needs to be found.
But , this is our problem and endless discusion on an American web site is not the answer. Discussion within the British Trade and investigation by the Proof Houses is what is needed . If indeed London is "blowing up barrels " then use Birmingham as they do not seem to have the same problem.
I say again this is a British problem ,washing our dirty linen in public is not going to help.
gunman, with the greatest of respect, I'd disagree. This is an international forum populated primarily with people who care deeply about British made guns - many of us consider them an international treasure and wish to give them the most sympathetic use and care possible. Some here are deeply interested in gun technology, including the various proof systems. It is my understanding that proof failures are uncommon due to the requirements for pre-submission prepration; a failure in testing usually means something in the preparation-viewing-firing schedule went wrong. When the failure is limited to one specific type, bulges in front of the chokes, one suspects a process failure rather than a speciman failure. Safety system process failures are alarmingandrequire an explaination rather than an "All clear!"
Yes, I do "peek at the works." I am unabashadly interested!! And,by the way,I do know a bit about testing.
All said in the spirit of comradship and with all due respect.
I spoke to the head of the gunroom at one of the best English makers last week, all three houses, Westley, Purdey and Holland are having problem with NEW guns at the London proof house. As I understand it there will be a meeting in the next week or so, best, Mike
Hear Hear Rocketman.
Mike B, that IS scary....something just isn't right. I just don't get why they don't say what has changed...something has...
T
Well said Rocketman.
What circumstances are required for a "new" set of "best" barrels to fail a "normal" proof test for such barrels?