Shotgun, 12 ga, 2 5/8” chambers

[paul harm]

I'm a little late to the party BUT, I don't know where some of you are coming from stating it's unsafe to shoot 2 3/4 in a 2 5/8 chamber. Have any of you done it ? I have nine old Remington SxSs, six are Damascus barreled, and have shot 2 3/4" shells in their 2 9/16" chambers for over 16 years with no ill effects. I also have three Parkers, and they were known for making chambers a 1/8" shorter than the shells to be fired in them. They claimed it gave a better seal. I quite measuring chamber length after reading Sherman Bells article on short chambers.
MacAR, I also have three 2 7/8" 10ga SxSs, all Damascus, and shoot then quite often on our SCs course. One is a Remington, a Parker, and a Lefever. They're just another gun till I slip in a 3 1/2 Dram BP shell. Then a couple of guys wake up.

 

[MacAR]

They're just another gun till I slip in a 3 1/2 Dram BP shell. Then a couple of guys wake up.

I used to do that, too. When I shot trap with my buds, I'd bring the ol' girl out and load 'er up with some light smokeless loads. Everybody wanted to shoot it, and then when the wise-acres started in, I'd slip a goose load in it (140grs of black under 1 1/2oz of #2's) and then stand behind them, to catch my gun! Had a lot of fun outta that old hammer gun.

Mac

 

[clang]

Some of it has to do with if you have a tapered forcing cone or sharp shoulders in the gun. A short chamber with sharp shoulders was designed before was a plastic shot cup and helped transition the shot load into the barrel with a minimum of turbulence. Firing longer shells than the chamber was designed for can create a pressure spike as the shot load leaves the shell.

A tapered forcing cone originally designed for paper shells usually has enough space for a modern plastic shell to open without creating a ring of restriction at the mouth of the open shell.

Many of the old guns were were also reamed to longer chambers and/or tapered forcing cone sometime during their life.

Look into your barrel. Is there a sharp shoulder at the end of the chamber? If yes, measure how deep it is. If it's less than 2 3/4" you probably don't want to shoot modern 2 3/4" shells out of it.

 

[paul harm]

Out of the 50+ old SxSs I've owned, only one had the stepped chambers, a early Parker 10ga. Someone correct me if I'm wrong. but those chambers were for brass shells. My chambers measured 2 5/8, and that's for a 10ga. Most the early 10s had 2 7/8" chambers. Only my Remington 10ga has 2 3/4" chambers - the Lefever and all my other Parkers have the 2 7/8 chambers.You'll find early guns that were made during the fiber wad days had shorter forcing cones. They were kept to around 3/4" so there wasn't a pressure loss. The back part of the wad was still in the shell while the leading edge was in the barrel itself.