doublegunshop.com - home Forums General Discussion German & Austrian Sporting Guns @ doublegunshop.com SKOPAR B scope

I'm looking at a German Sporting rifle with a SKOPAR B scope with see though mounts on it. It also has a set of off set single claw mounts on it. The front one is mounted on the rib a inch or so behind the rear iron/flip-up sight and the rear is mounted off the left side behind ring. I don't have pictures right now. They think it is chambered in 6.5x57. Was that a common pactice to have a rifle set up for to different scopes?

Not sure about how common the different mounting setups would have been but that scope is an old Voigtl�nder

R.Marshall,
It is not very common to have two scopes for the same rifle, but it is not unheard of either. One of my German hunting friends had a Heym Mod 33 Dural drilling 20/20X 5.6x52R with both a 4X and 6X scope. He used the 4X in the mornings and the 6X in the afternoons, because it was better in the dark. There is also the possibility that your rifle is one of the many that was separated from it's scope at the end of the war and subsequently had another one mounted.
Mike

Thanks for the info.
here is a few more pictures. I'm guessing the caliber info is under the scope mount.

R.Marshall,
From what I can see of the proof load, it is likely 8x57I.The proof date August 1913( 813) indicates the bore diameter and case legnth should have been shown under the barrel in mm.
Mike

I didn�t see anything else under the barrel. I have it on hold right now. Once I get it home I will investigate further. Thanks

Schilling forge mark plus 4000 ATM stamp.

The value in the stamp of >> 2,4 g GPB over St.m.G.<< stamp seems odd?







>>The CROWN + crown/N proofmarks stand for Nitro proof using the special "4000 atm proof powder". This proof was used from 1894 to about 1923.
The rifle was proofed for the M88 8x57I sevice load of 2.75(2,67-image) g = 42.4gr GewehrBlaettchenpulver = (military-)rifle flake powder behind the 227 gr Stahlmantelgeschoss = steel jacket bullet.<<
This is what I would expect to see?



Subject longarm....

Cheers,

Raimey
rse

That >>date code<< Ford mentioned is actually 313(6,25mm) - a bore diameter / plug gauge stamp.


Supplemental Proof table - sub - calibre .....

Cheers,

Raimey
rse

Thanks for the info Raimey. I was told it was a 6.5 something, the folks I�m buying it from said they thought the person they bought it from said it was a 6.5x57. I guess a chamber cast will have to be done.

Or slug the barrel. Odd calibre just from memory but as always just another enigma......

Keep us posted on this unique offering.....


Cheers,

Raimey
rse

Maybe a 7 x 57..:

https://www.alamy.de/stockfoto-karabiner...a-51539915.html

Wolfgang

Thanks for the replies.

When I took this rifle apart yesterday at my friends gun shop I was amazed at well this rifle fit in its stock. The inletting was perfect.

R.Marshall,
Disregard my previous post and see my comments in the GGCA forum. Be sure to use cerrosafe for the chamber cast, there is not much difference between 6.5x57 and 6.5x58P, both of which should have 6.5mm bore(278 gauge).
Mike

Thanks Mike.

Have you any ammo or brass that came w/ the rifle?

Cheers,

Raimey
rse

Unfortunately no.

I bought this rifle today. I plan to cast the chamber tomorrow. The safety is stuck in the fire position. Any ideas what is wrong?

R.Marshall,
If it is a transition action, it may or may not have the little spring loaded bolt shroud lock on the left side of the bolt shroud nor the projections on the firing pin that prevents firing if the bolt is not closed. If this is the case, the bolt shroud may just be partially turned. Can you post a photo of the shroud? I don't understand what the last photo is of.
Mike

The last picture above was a picture of the chamber.

R. Marshall,
OK, the latest photos clearly show you have an early transition action without the bolt shroud lock and with the early firing pin. Do you have any other rifle built on a mod 98 action? If so, it would clarify my description if you remove the firing pin/shroud assy. from both, and compare them. It is possible that instead of "cocking on opening", it "Cocks on closing" like 93/94/95/96 actions. Try opening the bolt, withdraw it a little, close it, then see if the safety works. I feel guilty about advising you to buy that dirty old thing and would be willing to give your money back for it, so you won't lose anything.
Mike

Thanks for the info Mike. No this is my first pre-war German sporting mauser. I had a M96 Swedish Mauser several years ago but sold it when I started buying German sporting firearms. I will check the "cock on closing" at lunch.

Let me kill a few deer with it first. lol

Thanks
Robert

It cocks when opening. It will chamber and eject a 6.5x55.

I also took the bolt apart and the safe works now.

R.Marshall,
Reading the serial number as 868( can you verify it is not 368), Axel dated the action as 1898-99. If it were chambered for 6.5x57 or 6.5x58 Port., it should not chamber a 6.5x55 Swed. original specification cartridge, because it had a larger diameter case head. American 6.5x55 ammo is often( if not usually) in cases with 06 head size cases so if you tried an American cartridge the test might not work. Mauser knew of the 6.5x55 and had the reamers because they developed the rifles for the Swedes, but the rifle was barreled in Suhl, rather than Oberndorf. If you used an American cartridge, a chamber cast might still be advisable.
Mike

I will take the stock off to get a better picture of the serial number and do a chamber cast tonight. Thanks for your help.

The serial number looks like 368

Serial number

My chamber cast pour ended up over filled and I ended up with cerrosafe in places it shouldn't be. Lesson learned, but here are a few numbers in millimeters.


The 6.72 in blue is a bore reading

Schilling forge mark along with 4000 ATM proof test stamp.


I've seen the script lowercase G attributed to Zella � Mehlis barrelmakers either Gottlieb Greifzu or Kurt Griebet. But I'm not sure if theses Zella - Mehlis mechanics could have attributed effort?


Cheers,

Raimey
rse

R. Marshall,
The serial number 368 falls into an area that is not especially firm, as to date of manufacture. Number 356 is thought to be from 1898 and 950 is estimated to be from 1899. Between these two numbers, no others have been attributed to a date( as far as I know).Many early actions are dated on the receiver ring, but yours has a clawmount base dovetailed into it, removing any date. Therefore 368 falls between 1898 and 1899 as it would if it were 868.Of course 368 is closer to 356 than 868, therefore would be closer to 1898 than 1899.
With regard to the caliber of the rifle, I believe it is not 6.5x58 Port. because that cartridge has noticeably more taper in the body and shoulder. Between 6.5x55 and 6.5x57, the differences are not so obvious. A chamber cast will always be larger in diameter than the cartridge, and a chamber cast from a bolt action rifle doesn't accurately indicate case length because of the space between the rear of the barrel and the bolt face; in opposition to a rimmed cartridge in a break open gun were the face of the rim can be located. In rebarreling several Mausers, in can say the distance between the rear of the barrel and the face of the bolt varies. The last one I did measured .102"(2.6mm), by my faulty memory. When added to the 54.38mm length from your chamber cast this would result in a case length of 56.98mm. This is too long for a 6.5x55. The head diameter of the chamber cast is shown as 12.30mm, the head diameter of a 6.5x55 is about12.04mm(about .010" smaller), and the head diameter of a 6.5x57 is about 11.86mm( about 0.17" smaller).For both cartridges, the difference in head diameter of the cartridge and chamber cast is within often encountered tolerances. Based on mainly my rebuttable calculation of case length, I think it is chambered for 6.5x57.
Mike

Thanks Mike!!!

R.Marshall,
Not knowing where you live, I don't know if there are any gunsmiths in your area. I think if you can find one with headspace gages, he can determine the correct chambering of your rifle. If it is 6.5x57, as I think, it will close on a 6.5x57 go gage, but a 6.5x55 should not. Headspace gages for 6.5x55 are more common than 6.5x57( in the US); if the bolt will close on a 6.5x55 no go gage it is likely 6.5x57, but if it won't it is likely 6.5x55. I hope this doesn't confuse matters more.
Mike

It doesn�t. Unfortunately good gunsmiths are far in few between in northeast Arkansas. If I have to I�ll buy the gauges.

I'm getting a lite primer strike with this transitional action. I think I have it cleaned good and bought some different spring to try from 22Lbs to 30Lbs. It did not fire with the 22lb spring. So I'm a little lost on what to do next.

R.Marshall,
If you already changed springs, you might check firing pin protrusion. Firing pins are sometimes damaged and replaced or sometimes "cleaned up"( meaning re-contoured, not actual cleaning), either could result in reduced protrusion. It is hard to ID a problem with out the rifle "in hand", some transitional actions were made with the new style firing pin that required the bolt to be fully closed or it wouldn't fire; it would have the two protrusions where the "Pin" part comes from the main body. The old firing pin wouldn't have this, it would be round here like a 93/94/95/96 action. If an old style firing pin was replaced with a new style one, the protrusions or maybe partially removed ones might interfere. This is also a traditional sign of excess headspace, but I did note you were using 6.5x57 ammo, and the chamber cast didn't indicate re-chambering to 256 Newton( a somewhat popular modification). If you have another Mod 98 Mauser, it might be instructive to test the rifle with another bolt and check the firing pin strike. If it is still too light, you might stack .004-.006" of shim material between the cartridge head and bolt face of the original bolt, and see if it closes w/o force.
Mike

I did get one round to fire the other day and the round was a little deformed.
the first pic is of the fired round primer.

I would call that quite a bit deformed. Better measure that fired brass and compare it to the chamber specs. Looks like a polished or possible re-cut chamber to me.

6.5-08? Neck down a 308 and try it.

My chamber cast

measurement at point of bulge on unshot ammo

measurement at point of bulge

Well, how about https://en.wikipedia.org/wiki/.260_Remington
No, you said a 6.5x55 chambers. You may have to work over a 308 case until you can get it to chamber and then fire form it out with a few grains of pistol powder and cream of wheat filler and have custom dies made.

The way the neck expanded could it be saying 6.5x58P?

R.Marshall
I think you can forget about the 260 or anything on the 308 case, they are too short. I'm leaning now toward 6.5x55 as suggested by SKB. I wouldn't think a 6.5x57 cartridge would chamber in a 6.5x55, but maybe there are enough tolerance differences in the right places to allow it. I note the 12.18 mm measurement you got from the fired case is about the same as the head diameter listed for the 6.5x55. My brother had a 6.5x55 rifle and used American cases in it( I think Rem., but maybe Win.). These cases did not have the larger head diameter, rather, they had the same size as 30-06/308/270. If you try an American 6.5x55 cartridge then, it will likely expand a lot also. It is hard to tell from the photo of the fired case, but it seems it has shortened some. This is common when a case expands a good bit ( the brass has to come from somewhere). Also I still believe the 6.5x58 P. has too much taper in the case and neck to be the correct cartridge. I went back to the earlier posts and the rifle does have the early type firing pin, I believe. Can you post a photo of the tip of the firing pin? You still have the problem of light firing pin strikes we have to work out(it would still be good to measure the firing pin protrusion).
Mike

Here is a picture of the PPU 6.5X57 unfired and fired in the problem rifle and some norma 6.5x55 unfired and fired in a Swede I onced owned.

Here are a few picutres of the bolt taken apart. It has the original firing pin.








This picutre is the pin in the bolt body without the cocking piece on the end to show no obstructions.

R.Marshall,
Now I'm back to my original assessment that it is chambered for 6.5x57. This is based on the photo, showing fired and unfired 6.5x57 and 6.5x55 cartridges. We still have the problem of the failure to fire. Except for the spring, the parts in the bolt are 120 year old original parts. Parts don't grow over time, and the rifle wouldn't have lasted through mounting and sighting in of two scopes and 120 years of use if it didn't reliably fire. From the photos, I can't see any repairs that may have been botched. This leaves us with very few possibilities for the cause(s) of the problem. If you told us earlier, I don't remember if it cocks on opening or on closing, and does the sear have the same number as the bolt parts? One of the most obvious changes during the transition was the shroud lock that was added but which was not added to your rifle. The reason for the lock was to prevent the shroud from "unscrewing" itself from the bolt during use. If the shroud is one thread short of being "turned up", there would likely be a failure to fire. The bolt body fits into the shroud when assembled, a foreign object inside the shroud could prevent it being "turned up" fully. The firing pin has three lugs, onto which the "nut" or cocking piece turns. You might assemble the bolt with one fewer of these lugs in the cocking piece, and check the firing pin protrusion in that mode. It is hard to troubleshoot a problem without the rifle "in hand", it is easy to miss something that would be obvious if you can handle the rifle.
Mike

Small ring receivers were a little soft and maybe the locking recess has been set back just a bit. The fired case should be a better fit than an unfired. Put a primer in the fired case without sizing and see if it fires reliably.

The shroud is screwed down to it meets the bolt handle and the cocking piece will only go on all the way. I'm guessing I'll have to find a firing pin.

R.Marshall,
You can get another firing pin and modify it, but you should keep the one that is in it as it is now. The last photo above shows the firing pin alone has plenty protrusion. Other photos show much less protrusion with the assembled bolt. I don't remember that you measured the protrusion, even though you have a dial caliper. I have found from making other firing pins that you must have enough protrusion that the primer stops the forward motion rather than the pin "bottoming out" on something. This transfers the energy to the primer, rather than some part of the rifle. Let us know what the problem is when you find it.
Mike

Mike thanks for your help.

I wonder which would be easier modifying a cocking piece or modifying a firing pin? or would messing with the cocking piece mess the bolt timing up? Because really it is the cocking piece bottoming out that is stoping the firing pin.

R.Marshall,
The transitional actions are intermediate length, I believe. This might give you a little to work with. You will have to modify the front end of the new firing pin any way to remove the two "lugs" that are not needed in the transitional action. It will take some careful measuring to come up with what you need. You may find the rear part of the firing pin too long, but I have modified standard length pins for use in intermediate actions. I did this by filing another groove ahead of the others at the rear and filed off the last lug that locks the cocking piece on and shortening the end to match the cocking piece. If you want to try modifying the cocking piece, get another one to work on and save the original parts. If you move the cocking piece forward, you will have to move the cut for the safety backward. This is confusing but when you examine the parts you will understand.
Mike

Thanks Mike.

I ordered a couple of new firing pins from Numrich to work with. If that don't work I'll try some used pins.

Well I ordered a new firing pin and it is works most of the time on Prvi Partizan ammo so I thought I would try Sellier & Bellot and first shot PING!! Case rupture! I don't think it hurt the rifle and it vented as designed. So I'm back at wondering if the chamber has been over polished or rechambered to something close to 6.5x57 or is it a 6.5x58P. Gunwolf had mentioned 7x57 very early but I don't think the bore is big enough for that. I would really like to get it up and running.

Time for a chamber cast so you can see what is really going on.

I guess I will measure the PP fire formed brass that didn�t rupture vs my old chamber cast measurements and see if anything matches. .257AI?

What does the chamber cast measure at the base and in front of the web? Fired cases? Un-fired cases?

Unfired case
Base 11.72mm
shoulder 10.85mm
Base of neck 7.53
Top of neck 7.44
Length of neck 7.52

Fired case
Base 11.88mm
Bulge 12.19mm
Distance From base to bulge 4.73mm
Shoulder 11.50mm
Base of neck 7.82mm
Top of neck 7.55mm
Length of neck 6.48mm

I am still a bit confused but I can tell you that at the point of your bulge you are measuring larger than a .30/06 base.

What does the base of the chamber cast measure? Start there to establish what the parent case is. It could be an over polished chamber or an odd ball cartridge.

Here is the chamber cast

Going back to your post # 557779 on 11/4/19, there is an excessive expansion of the neck of the fired case that is easily visible without measuring. Is this really a 6.5 m/m?

Then, assuming your Sellier & Beloit ammo was new unfired brass, there had to be a considerable difference between the case dimensions and the chamber for the brass to split as it did, and have a partial head separation, instead of just fire forming.

I'm thinking your light primer strikes were possibly caused by the firing pin pushing the case off of the bolt face because the shoulder was several thousandths back from contacting the chamber. This looks a lot like an excessive headspace situation, and the recommendation to measure with headspace gauges seems like a great idea. That might explain the strange deformation at the case-shoulder juncture, and the partial head separation in new brass. Was the primer very flattened, which could indicate that the case head was unsupported by the bolt face at the instant of firing?

I think I'd start with headspace and bore measurements, followed by another chamber cast, and careful measurements of the Cerrosafe at the correct time to get exact dimensions. It wouldn't hurt to find a soft lead ball slightly over-size to slug the bore, and get precise land and groove dimensions. It seems strange to not see even a trace of rifling on your chamber cast.

It is unusual that a chamber would be polished that far out of spec unless it was severely pitted. I don't see anything in 6.5 cal that has dimensions very similar to what you measured. This could be some wildcat round. Or you might end up setting the barrel back a couple threads and rechambering... or rebarreling. I'd sure be wearing good shooting glasses, or better yet, firing this rifle tied to a tire with a long string on the trigger, until you get this sorted out. I once spent about a half hour totally blind in both eyes after having a complete head separation with a VZ-24 Mauser rechambered to .22-250. That gets your attention, and it isn't worth taking such risks.

I am having a hard time finding something that is that large of a diameter and so short. I am leaning more towards a damaged chamber that someone has tried to clean up. I'll keep looking but that is my feeling at this point.

If we are considering wildcats now, has anyone thought about 6.5-284 ?For the "life of me", I can't imagine anyone rechambering an early Mauser to any wildcat, muchless 6.5-284;but it was popular, for a while, with people chasing it around like they are doing the 6.5 CM now.
Mike

How about one of the .257 Roberts?
.257 Roberts
.257 Roberts AI
6.5-.257

No, no, no The base diameter on those cartridges is 12.01mm or .473", much smaller than your chamber 12.3 or .484", a 6.5x57 is even smaller at 11.9mm or .469",this is what makes me believe you have an over polished chamber.

Your issue is the diameter of your chamber at the base and at the point of the bulge is larger than your brass by more than tolerances allow. Some of the brass when pushed this far is failing. I converted the measurement in MM to inch and can not find any cartridge to match. Do you have a micrometer that measures in inches? The chamber should only be a couple of thousandths of an inch larger than your brass. As mentioned above, this is very dangerous.

Yes I have a micrometer that measures in inches.

A very accurate measurement taken at the base with your micrometer will help.

The base diameter of 6.5x55 Swedish is listed as 12.1 and the chamber would be larger than that( in Europe),but as mentioned before, American factories commonly make cases with 06 size head diameter without obvious problems. I think a chamber cast is necessary, even if you have to pull the barrel to get a good one( measuring case length would still be tough).
Mike

Could be a 6.5x55, I looked past it due to length but with the difficulty measuring it you may be on to something.

I�ll bite the bullet and buy some headspace gauges also. I really want this rifle to work. What gauges should I get? No-go, go or both?

I can take a bullet out of a 6.5x55 and try a fire form and we can see what happens. Or is that a waste of time?

Headspace gauges are not needed until you are sure of the gauge, they are quite expensive. I have quite a few and could lend you some if I have the caliber you need.

Firing form a 6.5x55 case sounds like a very safe option that should give you some valuable information. You will want to use a fast burning powder when you fire form.

I agree with the idea of fire forming with a 6.5 x 55 case and fast burning powder to get the the best fill out. I also agree that you shouldn't buy any headspace gauges at this point, due to the cost and the fact that they may not be what you need, and you may never use them again. Another option to see if you may have an excess headspace situation would be to cement round pieces of thin plastic shim stock of various thicknesses to your 6.5 x57 cases to see how much makes it difficult or impossible to close the bolt. It doesn't take very much to cause excess case stretching, or partial or complete head separations. At this point, it is impossible to know if you are dealing with an obscure standard chambering, a wildcat, or an over polished chamber. Here's a silly question... any chance of contacting the original owner to get some clues?

I'd still recommend slugging the bore too. And another chamber cast with very careful measurement at the correct time after casting is a good idea. You already have the materials.

If chambering a rifle for a caliber I don't have access to headspace gauges for I sometimes use a factory cartridge with one thickness of tape on the head for a go gauge and enough thicknesses to make the normal difference between the gauges for the no go( usually .003 or .006"). I usually use masking tape because it is "on hand" and easy to trim to fit the head. The same idea as Keith's, different material ( this is a "make do" solution, not the preferred one). Be sure the cases you to fire form with a European case rather than a smaller American one.
Mike

It is Norma brass.

I will try the masking tape trick first.
I have some Bullseye powder on hand. How much would I need to use to fire form or to see if this case moves much? I have seen 11-11.5gr mentioned to fire form .260.

when using the tape to check headspace do I feed from the magazine?

R.Marshall
No, don't feed it from the magazine. It is preferable to remove the extractor( you don't have to remove the retainer, just have a scribe handy to turn it around if necessary to remove the bolt). You can slide the case under the extractor by hand, you just lose some sensitivity of feeling( the tape is somewhat compressible so don't "crush" it closed). The Bullseye load should work. Tamp a quarter sheet of toilet paper over the powder, fill the case with polishing media/corn meal/ grits/or cream of wheat and plug it with toilet paper/ foam/ wax/ etc. If it doesn't fill out the case, increase the powder. Avoid using a bullet with any significant amount of Bullseye.
Mike

RM, When you fire a case-forming load, don't have the muzzle near anything you don't want damage. High velocity corn meal is more serious than it sounds.

well I fire formed a pcs of 6.5x55 norma brass with 11gr of Bullseye and coffee and a pcs of cotton ball for plug. The primer is slightly bulged.

unfired brass in inches
base .4760
shoulder .4325
bottom of neck .2950
top of neck .2930
lenght .215 60

fire formed brass in inches
base .4760
shoulder .4550
bottom of neck .3080
top of neck .3025
lenght .214 95

Original cast with cerrosafe in inches after cooling
base .484
shoulder .457
bottom of neck .311
top of neck .300

original drawing of cast measurement in MM after cooling and where my measurement were taken on brass also

would it be interesting to fire form a .257 Roberts?

It seems awfully close to .257 Roberts AI going of the fire form brass but not a exact match.

R.Marshall,
I have come to the painful conclusion that I don't know what the heck it is chambered for now. It seems to have been chambered for a standard early German cartridge and underwent some unfortunate attempt at rechambering to something that was available, and is now unidentifiable. If it were mine, I would fireform a couple more 6.5x55 Norma cases, "slug" the barrel to insure it is 6.5mm(.264" about) and send the fireformed cases to CH4D to have them make a set of dies to fit the chamber. Then you can treat it like a wildcat, load to 6.5x57 pressures, call it whatever suits you( 6.5 Marshall special?) and kill a pickup truck load of deer with it.
Mike

Mike thanks for your help as always and everyone else that has replied with advice.

You might try just neck sizing after fire forming and can likely use 6.5x55 dies or something similar set so they do not resize the case. As long as you do not own two rifles in the same caliber this method works very well.
Steve

Thanks Steve, that sounds like a good method. Thanks for all your help.

You are more than welcome. If you use the neck sizing technique be sure not to move the shoulder on the fire formed case.
Steve

SKB, R.Marshall
I use that neck sizing trick for several of my rifles, even sometimes shortening the sizing die. I don't believe it will work in this case, because the fireformed cases seem to be "blown out" larger than the normal 6.5x55 chamber. If you have a die set made to fit, then it could be used to neck size for other rifles. Of course, as always, I could be wrong.
Mike

A larger body die may then work, 6.5/06 etc. just have to play around with it but I think something may work in place of a custom die. I as well could be wrong.
Steve

Steve,
06 diameter is smaller than 6.5x55, maybe 6.5 Rem. Mag., but they are pretty rare too. I know custom dies are pretty pricy, I had to have one made to form 6.5x58R S&S cases in a couple steps. I made up one for fireforming with about 5 different dies. It formed OK but it was more trouble than it was worth for a rifle I planned to keep.
Mike