doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com "In" and "out" of proof?

A couple of points do come to mind. This gun may well have been made with oversize bores for use with all brass shells. In 1872 the 11/1 marking had not come into use. It could thus have started life of a size Just Shy of taking the 10 gauge plug of .775". The bore may not have been enlarged more than .005"-.006". This could well account for the thickness of the walls which would seem unlikely had the bore actually been enlarged some.030".
Technically though, yes it's out of proof. With that kind of walls, I wouldn't concern myself about that.

Miller, That insight is very helpful. The gun is otherwise in superb condition. I suspect it went fowling a time or two and has been languishing in a gun safe for the majority of its existence. It digests the 10ga RST 2 5/8� 1 1/8� shells nicely.

Owen;
In your original post on this gun, you had just stated that the bore was proofed at 11 with no mention of the chamber. I had been thinking all this time it was an oversize 12. It makes a lot more sense as a 10. That would certainly account for the heavier walls etc. Most likely it has been enlarged but very little from where it started but when proofed the proof house marked it as per the larges plug gage it would accept.
After 1887 it would likely have been marked as an 11/1 but was still probably actually nearer to a 10. That was a major fault of that system which it took many years to correct by marking actual bore diameter, rather than using a series of plug gages.

ah so...so it is a 10 gauge gun after all...

sounds like a fun gun to shoot...

Somewhere in my files I have correspondence from someone who bought a 12ga Elsie, Damascus barrels, 2 3/4" chambers. His club wouldn't let him use the gun at their facility. He had it sent to the UK, got it back, passed CIP "standard" proof (850 bar). What shells to use in the gun? The Brits said any standard 12ga load--which, to them, means "standard proof", NOT superior or magnum proof. I pointed out to the individual that SAAMI service pressure for the 12ga is 11,500 psi, while CIP standard service pressure is 10,730 psi--so he likely would not want to use typical US 12ga loads in that gun. But especially with 2 3/4" chambers, it'd be very easy to work up loads well under the CIP standard service pressure limit.

We're still not quite speaking the same language as our British cousins when it comes to certain topics (like pressure). But if we take the time to understand what they're saying, we can safely use their guns (and our own vintage guns) with modern ammunition. Either British/European, RST, or our own reloads.