doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com New poster w/ a question

Gentlemen,

I've long lurked at this site, and believe I've even corresponded with a member here related to one of my father's doubles (An Alex Henry 450-400 2 3/8's BPE).

I recently inherited all of his British doubles, and had a question related to his Alex Martin 12 gauge. I am hopefully deducing some of the marking correctly but could use some eyes that know what they're looking at.

my two questions are: Would you shoot a 1 ounce load of #5's from RST (2.5 inch shell) in this gun and how do you tell how it is choked? I'd very much like to use this gun in honor of Dad when I get out to chase grouse both in the mountains and on the plains.

Here is the photo of the proof marks:



Many thanks for any information, this site has been invaluable in figuring out how to load for the three BPE's that dad had.

By proofmarks yes you can shoot 1 ounce load of #5's from RST (2.5 inch shell)

But there is more to it than just the proofmarks, the actual condition of the gun and its barrels is part of this as well.

The full answer is you should have minimum wall thickness check on the barrel wall by a good gunsmith.

If you have some good gun sense you could perform the inspection yourself, but without a little experience you should defer to an experienced inspector


On choking you get a gauge measure the bore before the choke (2-4 inches back of the muzzle then again the bore at the muzzle and the difference is the amount of choke. Any good gunsmith can do this for you if you do not have a gauge for it

Hello Ben Lamb
Welcome on your first posting
See here
http://www.shotguns.se/html/uk.html

http://www.doublegunshop.com/forums/ubbthreads.php?ubb=showflat&Number=296927

Best way to check choking is to fire and evaluate
Mike

Hi Ben,

Here is what I see from the marks-

The gun was nitro proved in London for 1 1/8 oz. loads and the chambers are obviously 2.5" long.
Barrels are dovetail lump and were re-proved at some time. At the time of re-proof, the bores (9" from the breech) measured .736" in diameter and this can give you an indication of how much that they have been lapped.
There are no choke markings on the barrel flats so either the gun has no choke or the marks were struck off at some time. You must measure the chokes as described above to determine what the choke is. Choke tools that do not tell you the difference between the bore and choke are useless.

You must measure the bore diameter and determine if the gun is still in proof. If the bores measure more than .746", then the gun is out of proof. You must also measure the minimum wall thickness to determine how safe the bores are. You will get many different opinions about wall thickness here so I may as well give you mine. If the walls are over .020" thick at their thinnest point and the bores are still in proof, you are good to go with either low pressure loads or CIP approved ammunition.

The gun was re-proofed in 1986 in London.
State of prood in the USA is a bit of a red-herring unless you are looking to sell as it can effect value but has little to do with safety.
Wall thickness, barrel condition, changes is chamber length, lump integrity and jointing are the important safety issues.
Chokes can be 'adjusted' by use of appropriate ammunition.
The fact that it is marked 2 1/2" does not mean it is still so chambered. Many guns in the USA have had their chambers 'dropped' but never re-proofed. Best to get them measured.
Enjoy!

Many thanks Gents. My take on the gun is that it's in good shape. It certainly looks like it's been hunted over the years with the usual scrapes and dings in the wood that comes from seasons in the fields. It locks up tight, and while there is a little leading in the barrels, nothing that doesn't seem like it would clean up with some elbow grease.

I'll take the gun to the Smith to get the bores & Wall thickness measured properly. At the muzzle, the barrel thickness measures .032 for both. That's with my reloading caliper though and not a micrometer. I plan on reloading for this gun, so the actual PSI information is hugely valuable. Many thanks!

Here's another photo, Dad had great taste: