The SAAMI meeting where it was suggested that manufacturers begin marking the chamber length on there guns was in 1937. Savage began stating 2 3/4 inch chambers in their 1938 A.H. Fox catalogs and marking the guns like this by 1939 were marking the guns like this --

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Remington got around to it by about 1940 --

1935 Sportsman --

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1940 --

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December 1940 Parker --

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[QUOTE=Dean Romig;336261]James, do you think those stamps are original or might they have been stamped by a smith who lengthened the chambers? No offense intended, just asking...

And which of your vintage SXS's are stamped that way, if you don't mind?





.[/QUOTE

I know all the ones on my LC Smith's are original, that is the ones that are stamped. The LC Smith's that are not stamped are 2-9/16" chambers. I'll have to check the AH Fox guns I have and some of the other SxS's in the safe.

Dean: Just as a note... I have had some experience shooting 2 3/4" ammo out of a 2 9/16 chambered 16 ga Euro gun. the 2 3/4 loads kicked noticeably more then the shorter shells. This was caused by the forcing cones being bored for the short shells not being able to allow the entire crimp on the shell to open completely. You might notice on the 2 3/4 ammo that the very front of the fired shell is somewhat "frayed". I now shoot nothing but 2.5" out of that and other short chambered guns. I dont know what shooting the longer shells does to pressures but I do know they kick noticeably more.

JMHO

Right Bruce, they do kick a bit more and I would probably say the cone ends of the plastic shells are more pinched.

I have read however, that the increase in chamber pressure amounts to something like 100 psi and IMO that’s a negligible increase and in the realm of chamber pressures of from 5,000 to 8,000 in these old guns I’m not especially concerned when it comes to this stout DH.

But that’s just me. By no means am I suggesting others do the same.



.

Do you think the 2 9/16” chamber was for 2 5/8” shells?

Could be. Did they make a 2 5/8” shell in 1898?





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In the early days, the 2 5/8 inch paper case was the "standard" 12-gauge shell. The 12-gauge 2 5/8 inch shell could be had with loads up to 3 1/4 drams of bulk smokeless powder pushing 1 1/4 ounce of shot. Circa 1907 all of our U.S. ammunition companies dropped 1 1/4 ounce loads from the 2 5/8 inch 12-gauge shells. From then on one had to go to 2 3/4 inch or longer 12-gauge shells for 1 1/4 ounce loads. The Remington Autoloading Shotgun, the Remington Repeating Shotgun, the Winchester Model 1897 and the J. Stevens Model 520 pump were all made for 2 3/4 inch 12-gauge shells. Our U.S. ammunition companies continued to offer 1 and 1 1/8 ounce 12-gauge shells in the 2 5/8 inch case up to WW-II --

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In that the 2 5/8 inch shell was considered "standard" most boxes up to the later 1930s don't have the length given on them. If they were for the longer 2 3/4, 2 7/8 or 3-inch they are so marked. Same with the 2 9/16 inch 16-gauge and the 2 1/2 inch 20-gauge, no length marked on the box?!?

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