Was given a box with 81 bullets it when I bought a used scabbard. They are a Speer semi-jacketed semi-wadcutter weighing 220 grains, in .410"
Wondering how they'll shoot in a microgroove Marlin 1894 FG (have not slugged it for groove diameter), and at what speeds I should best push them to [I may need to chamfer the rifle's throat to get them to feed. I have not loaded any in cartridges yet, but other .41 Mag LSWCs do not feed in this action]. Regretfully, I no longer own a revolver chambered so. It had timing issues and I was offered a fair price for it.
Powders on hand are the usual whirlenpopper suspects: Unique, 2400, Viht N110, Green Dot, Bullseye, TiteGroup, AA7 and AA9.