doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com chokes

American "Old" system:

12ga .729" bore

cyl=.000
skeet in=.005
i/c=.009
skeet out=.012
mod=.019
i/m=.025
full=.035

American "New" system

cyl=.000
sk in=.005
sk out=.008
i/c=.010
light mod=.015
mod=.020
i/mod=.025
light full=.030
full=.035
xtr/full=.040

I'd think the Brit system would imply 10, 20, 30, 40 pts but I could be, and probably am, wrong. I rely on Jim to tell me when I'm wrong and have never been disappointed. Incidentally, that first chart is the strait poop from "Mikey" Orlen.

jack

Salopian, could you expound on those "scientific tests" that proved imp modified and full are the best all around chokes for hunting? Whoever came up with the test sure as devil never hunted Ruffed Grouse in thick cover. I just can't imagine such a generalization holds true for all types of game. Maybe the tests showed such choking suited English driven birds or waterfowl. And since we are already into our uncommon language usages, I was under the general impression we do a lot more bird hunting in USA whereas you do a lot more shooting of birds in British Isles. The distinction being whether the guns are moving to find birds or are waiting for them to arrive on cue. We do some shooting too for Doves and waterfowl.

rabbit (or others): Where can I read more about these "old" and "new" American systems of choke designation, including an explanation of the migration of the "Skeet Out" designation in relation to Improved Cylinder, and of In and Out's relationship to the "Skeet 1" and "Skeet 2" terms I hear more often in my neck of the woods. Didn't Winchester use the latter, and what measurements did they correspond to? Thanks. TT

TT, the first abbreviated system came from Mike Orlen because it has the "Choke & Chamber Music" Logo at top of page. I cannot remember where I got the "New System". It is copied out in longhand at bottom of the photocopy of the Orlen photocopy and I remember it being called "New System". Possible I got it from Browning or Remington website. I checked again and the Orlen chart does use Sk1 and Sk2 nomenclature rather than Sk in and out. I can't explain why the two skeet constrictions bracket ic in the Orlen chart but are both less than ic constriction in the other. I don't know the constrictions of the Winchester designations for solid chokes. I have always heard that they are much more open (less constriction) than their nominal counterparts in Browning solid chokes.

jack

Jack: Thanks. Yes, in my experience, continental guns tend to be more tightly choked, compared to American and British guns with the same choke designations, Browning being a good example of this. Not sure how Japanese guns compare. Just as an aside, I've also heard that Winchester chokes from the great modern era (approx. 1925-75, maybe?) are typically very accurate and well-bored. TT

More choke charts:
http://www.shotguncombogauge.com/multiboregauge.html
http://www.colonialarms.com/chokespecs.html
http://www.hallowellco.com/choke_chart.htm


16 gauge Browning-- Remington-- Winchester
Bore diam. .665------- .673-------- .664
Full Choke .628 (.037) .640 (.033) .633 (.031)

Modified .640 (.025) .656 (.017) .648 (.016)

Imp. Cyl. .649 (.016) .665 (.008) .657 (.007)

No apologies needed for the inbreeding. I live in Utah.
You can tell you're at a typical Utah wedding because the bride will not be pregnant, but her mother will.

I'm with Jerry on questioning how one set of chokes could be "best" for everything. Come on over here and hunt up some valley quail in thick brush with those chokes and you'll be wanting a cylinder bore and mod combo within the first hour. Or over to Arizona and hunt up some Gambels quail. A modified first barrel will put nice saucer sized holes in the brush most of the time and if you ever hit a quail with it on the first shot, it'd be ABC (already been chewed) bird.

Jerry & Chuck,
My original post on this subject was in answer to the original question "what is your opinion on opening my choke from F&F?"
My reply was advice to consider Half(Mod)& Three Quarter (IM)based upon my Field experience and scientific tests.
My Field experience encompasses mainly, Driven High Pheasant, Wildfowling, and Pigeon Shooting.
The scientific research I mentioned is based upon my interpretation of research which is ongoing by BASC in conjunction with CONSEP which is available on line by going to the relative organisations websites.Obviously we all know that in any debate numbers can be crunched to favour either side of the argument.
Back to the plot.
It is my fervent belief that it is better to have adequate patterns to ensure the humane despatch of any quarry I shoot at.
There is no doubt that if you put enough pellets from True Cylinder into your quarry you will despatch it but the real problem is accurately judging range, which we have all proven we are generally poor at doing.
If I was Snipe shooting, Quail shooting, Dove, Decoyed Pigeon shooting I would prefer Quarter choke or less.
But with a fixed choke gun for general purpose shooting I would favour Half in both or Three Quarters (IM) in the second barrel.
Indeed originally many fixed choke Continental Game guns featured choking of 1/4 & 3/4 and two Italian guns I have with 1/4 designated choking actually throw patterns nearer half choke.
When we have knowledge and experience, we know wether to take that shot or not based upon the belief we have enough pattern to despatch the retreating bird or not to take the shot at a close bird because of the belief we may damage the meat.

Here is food for thought, In early trials it as been found that out of 100 participants (mainly clay shooters) it was found that under 30% achieved a strike rate of 6 ex 8 at 30 yds.Only 8% succeded at 40yds.
These tests were on a clay crossing at about a height of 12ft 90 degrees to the shooter crossing left to right, level flight, and a report bird right to left.
Also a driven overhead tower bird at 30 yds high and 40 yds high.
Before you scoff, try it, no practicing, 8 shots only, straight in.
Let me know how you get on.
In fact let CONSEP know how you got on.
Good shooting.

No doubt many can't hit 6 of 8 crossing clays at 30 yards. To hit at that range consistently, you have to continuously practice at shooting at the distance or longer. Note to self: It's been a while since you've practice 30 yard crossers.

Cooperative North American Shotgunning Education Program (CONSEP) and Tom Roster are familar names to most USA waterfowlers. And from what I can tell it looks as if other countries are using the CONSEP charts for shooting waterfowl with steel shot. That chart is an excellent guide.

Reading some of the articles on the BASC site, it looks as if research is showing that half and three-quarter choking are the tightest that should be used, depending on shot size. Since you do mostly pass shooting half and three-quarter would be the most logical. But that somewhat goes agains what the London houses have been saying and selling to their USA customers as read in the sporting magazines. My experience with quarter/half and improved-cylinder/half chokings is that they are better than half/three-quarter when rough shooting.