I hunt with a older investarms 36 I use 3 f from 18 to 35 hrs. 350 RB with.015 patch. At 30 grs or above I sight it in dead on at 50 yards. Killed a lot of squirrels with that load.
I don't think this is as big deal. I shoot original English double barrels made this way. Pull wedge remove nibble if percussion and plug fill barrel with boiling water. Leave set a few minutes. Push wet patch or mop down bore remove plug then stick barrels in pail of hot water pump water in and...
WOW. I have a small collection of Original 12gauge and 14-gauge double barrels that I hunt with and shoot regularly but none are as nice as yours. I really want a 11 gauge in a Moore or Mortimer. Yours with the travel case is really special...
I'll say this I have several Original English double barrel shotguns. And a few of them have a combination of filed screw head on a angle to match the tang and also a larger countersink hole. And diameter of the head made smaller. But if the wood was to srink That does create a problem tighten...