I recently purchased a 10 bore double proofed for a 2 1/4 oz load. Barrels indicate this was a 3 1/4" shell. Nitro proofs. Believe the gun is from the mid-1920s.

Any suggestions for where to research an appropriate 'heavy' load? I expect most use will be with 2 7/8" ammo, but it would be interesting to see what performance, and recoil, is like with the loads marked on the barrel flats.

Any help would be appreciated.

Regards,
Chris