I built this little carbine last year, H&R SB2 receiver, 20" 45 Colt Classic Carbine barrel reamed to 454 Casull (rifle chamber reamer) and stocks that I carved and finished (though I sent it out for checkering). It is great fun and shoots everything from PB 185 gr soft lead over Trail Boss to 300 gr LFN GC very well. With the Hornady 250 FTX it has chrono'd at 2250 fps.
I would like to have a go with some of Buffalo Arms 350 gr pure lead cup base paper patched bullets in 454 brass, but I don't do black powder. I was thinking IMR4227 at around 1350 fps?
In any event, as you may have already noticed, I am clueless on the subject of paper patching. I have slugged the bore and leade at: bore .451", groove .454" and leade at .455". Based on that info, what diameter bullet should I be starting with .451, .452? And what diameter should I patch to?
Any and all wisdom most welcome. I appreciate that you may be followers of the satanic black powder, but I'm not ready to go there yet. Baby steps...