Black Powder or Smokeless Powder?
 

How can I determine if a shotgun is intended for black powder or smokeless powder shells?
For example, I have a Riverside Double Barrel Shotgun 16 Gauge with Exposed Hammers made by J. Stevens Arms & Tool Co. I think it is a model 215 and Produced between 1914 and 1924. I think it shoots a 2.5 long shell, although I shot a 2.75 long shell in it.
I'd like to know for sure if it for BP shells and is it for 2.5 long shells.
I don't know of a "gunsmith?" in my are that I trust.

Mule

Re: Black Powder or Smokeless Powder?
 

If it has damascus barrels it's bp only. If it doesn't you're good to go with shells the proper length. I grew up shooting damascus barrels with 2 3/4 smokeless shells but I don't recommend it. When you shoot a longer shell the crimp opens up over the forcing cone and raises pressure dramatically.

Re: Black Powder or Smokeless Powder?
 

If it's manufactured after the turn of the century it's a fluid steel barrel and designed for smokeless. You will be able to tell in a hurry if it's a 2 1/2" chamber when you shoot the longer shell it should drastically fray the end of the hull. My guess though is it's a 2 3/4" chamber designed to shoot a paper hull. You might want to have the forcing cone lengthened to take the plastic shells.

Re: Black Powder or Smokeless Powder?
 

A 2 3/4 inch shell will fit fine in a 2 1/2 inch chamber. So that tells you nothing. The correct way to tell is with a chamber gauge. That will cost you about 80 bucks, so you may not want to go that way.

A cheaper way, if your local gunshop will let you, is to just bring in the barrels (that alleviates the worry about "loaded gun in the store") Drop a 3 1/2" shell in the chamber, and mark on the side of the shell how deep it goes (I just used a sharpie). Tnen measure from the bottom of the shell to the mark.

I say to use a 3 1/2 inch shell, because a 3" will fit in a 2 3/4 inch chamber. 3 1/2" won't.

Once you've measured the distance (and now know the length of your gun's chamber) just put the shell back in the box and put it back on the shelf. You haven't hurt it any - it's just got a magic marker line on the side of it.

Re: Black Powder or Smokeless Powder?
 

There were still some damascus barrels being made into the 20's. No it wont fray the shell but shooting a 2 3/4 shell out of a 2 1/2 inch chamber raises pressure drastically. Good point about the forcing cone.

Re: Black Powder or Smokeless Powder?
 

To all, thanks for the continued answers