doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Is it a 2 1/2 inch or 2 3/4 inch chamber if it is

Pooch, Now that you have the gun in hand,why not take it to a gunsmith and have him read all the measurements of the barrels? This might be the best way to know what's what with your gun.

My source says the 12 over c in the London proof means chamber over 2 1/2. The 12 over c does not define chamber length in the Birmington proof house. Surprisingly the gun has been proofed in London

I'm done....

Hi Pooch, as been said, the 12C, just means that the gun is a 12b(ga) gun. It has nothing to do with chamber length. It does not matter what proof house, London or Birmingham.

Army & Navy did not make any guns at all, they were an oulet, that when they first started supplied, various sporting goods (to include guns of course) to Officers of the Army and Navy of the UK. Most of the guns were supplied by the Birmingham trade, but a gun could be proofed in either house, regardless of the region, maker or where the gun was sold. Charles Boswell was a London Maker who had his guns proofed in Birmingham after a "disagreement" with the London Proof House.

If you can, please post pics of the bbl flats, that sure would help!

Col. I stand correct on my one post, I done forgot about the Rules of 1904-1925 and shot charge....good catch.

Best of Luck!

Greg

Reference I'm using
http://proofmarks.tripod.com/englishproofs.html

They simply didn't word that listing very well. 12/C means any chamber shorter than a 12/LC. There has for a long time been controversy over which mark a 3" chamber would have, but not a 2�" one. A 2�" chambered gun would bear the 12/C mark as would a 2 3/4" one. A 3�" chamber would for sure carry the 12/LC mark leaving the 3" the only one really in question.

Aha! Thanks! Having little to no experience with a London proofed gun I was quite willing to read it to mean what I wanted it to do.

Hi Pooch, don't worry! There are so many ins and outs to the English gun trade, even guys who have had years of experience with Brit guns have had curve balls thrown at them at times.

There are no absolutes in Brit guns like anything else.

It just takes time, first hand expierence and lots of reading and learning from others (like on this forum).

Good Luck to you!

Greg

THERE IS A GREAT ARTICLE BY SHERMAN BELL "LONG SHELLS IN SHORT
CHAMBERS" IN THE WINTER 2001 DGJ THAT WILL ANSWER A LOT OF THE WORRIES ABOUT SHOOTING 2 3/4 " AMMO IN SHORT CHAMBERS. IT IS LONG AND COMPLETE WITH EXCELLENT DATA.
THE RESULTS ARE THAT IT INCREASES PSI A FEW HUNDRED LBS, GENERALLY IN THE 500-600PSI RANGE EVEN WITH FEDERAL PAPERS.

Definitely some poor wording on that website, Pooch. As noted above, 12 over C doesn't tell you anything for sure about chamber length, on either a Birmingham or London-proofed gun, except that it's no longer than 3".