doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Thoughts on possibly buying a Birmingham SxS...

2-piper, doesn't "13" mean .719 to .724 and "13/1" mean .725 through .728?

Hi, once again Mike is on the mark. I do agrre that 3k is a bit high for a BLNE. Of course condition is always a major factor and to some extent the maker.

Who is the maker BTW?

1 1/8oz is the standard shot charge for 12b 2 1/2" guns. During the First World War factory loaded shells were loaded with only 1 1/16oz of shot, to save material for the war. Markers just continued to use this charge after the war. This is why most 12b 2 1/2" shells today are only loaded with 1 1/16oz of shot.

I think you may have made a typo, the 1/31 should be 13/1. If so this means that the gun is a 13b and was so stamped under the 1925 Rules of Proof. It's still a 12b, just means the bore is tighter.

The 12C in the diamond indicates 12b and chamber size as Mike says, but it could also mean the gun could have a chamber length of 2 3/4" (which was used for heavy waterfowel guns). A general guide is 2 1/2" chambers are proofed for 1 1/8oz and 1 1/4oz for 2 3/4".

Anyway, this is a very good discussion. To bad we can't see a pic of the bbl flats, that would tell the whole story.

Here's a link to the Birmingham Proof House, it may help you out:

http://www.gunproof.com/

Good Luck and all the best!

Greg

Joe;
12ga = .729"
13ga = .710"
14ga = .693"
15ga = .677"
16ga = .662"
To find dimension for 13/1 simply add the .729" & .710", Divide by 2 & drop (don't round) beyond three decimal places. thus .729+.710/2 = .7195 & drop the .0005.
You were right in theory, but somewhere picked up the 13/1 dia for 13ga.
The full gauges are worked by a mathamatical formula & all "Rounded to three decimals, but the in-between sizes are averaged & simply dropped to three places.
Beginning with 10 ga where there are two in-betweens the steps are 1/3 & 2/3 of the space between whole gas, & still dropped to three places, not rounded.

A 1950s W&S Model 700 found its way into my truck somehow a few years ago. I've been very pleased with it. Case colors are mostly gone, but it is a good solid shooter that I take care not to feed overly large fodder.
So far I have used it for skeet and phez; it does fine at both.
Its choked IC and MOD, 28 inch barrels and 2 triggers of course.

Best,

Oops, thanks 2-piper. My brain slipped a cog. Thanks for the data.

In Burrard's Volume III first edition page 208 he gives 1-1/16oz as the standard load for 2-1/2" nitro shells. This was written in the ninteen thirties.


Best,

Mike

Yeah, and when I read it my dyslexic mind translated it to 13/1 and I never noticed it wasn't until I read your post.


Best,

ekMi

Here's a bore size table I have on my wall. Shows the minimum for each bore size.

A true 4 gauge bore is 1.052", though most 4 gauge shotgun bores run closer to 6 gauge & will be so proofed. I have ben told, but cannot really verify, that the original 4 gauge guns were built with brass cases. When paper cases began to be used rather than change the chamber they dropped the bore diameter. Makes sense at least. Not positive but 4 gauge rifles may have preceded the shotguns in this size.

I shot a four bore rifle ONCE......have no idea where the ball landed--I was taking a nap on the ground......