sxsman1, Cabela's sells Gamebore Shells, made in England. 2 1/2" 20 ga., and 2 1/2" 16 ga. and 2 1/2" 12 ga. (65 MM). The price is $8.99 a box. Most have 28 grams of shot (1 oz) and are lower pressure. They used a fibre wad.
There is also a few sites you can go on, and find reloading data for 2 1/2" shells. You can also take 2 3/4" shells and cut them to the right size to make 2 1/2" shells. For 16 ga. go to
http://www.16ga.com . If you ask I'm sure someone will give you reloading advise, that is if you reload.
There are some loads there as low as 4400 PSI, and 1100 fps.
I wouldn't go any higher than 7800 psi in your gun.
Also I definitely would not alter the chamber of your gun, as some have stated it was not made for modern loads. David
