I have a Rossi R92 (lever gun), SS, 44 mag, 24" barrel. The groove in this rifle is fairly large (.4330", .4330", .4326"). I tried to measure the bore/lands from a slug, but couldn't get a reliable measurement. I do however have some minus pin gauges and the .426" (.4258") pin fits loosely in the barrel, while the .427" (.4268") will not quite enter the muzzle (no surprise with the .0004" squish). I have done some fire lapping and have knocked off the really rough edges and it feels good enough to at least try some cast bullets in it.
With this size bore/groove I thought PP might be the way for me to to run some cast bullets for hunting without much expense (custom cast GC .434" bullets at $0.35 each, or custom molds and etc). Especially since I have not yet entered the world of casting.
My initial thought was to buy some economical 240 gr, .429/.430" commercial cast bullets, sized them down to .427 with a Lee bullet sizer, patch them, and then final size with another Lee sizer honed out to .434" (I already have one at .4338"). FYI, I loaded a dummy round with a .4347" slug and it chambered just fine. The throat however is pretty long and rounds that reach the throat will not cycle.
But after reading the stickies and many other posts, I am beginning to doubt myself. It seems as though I have the cart before the horse. PP is not in lieu of casting, but rather another part of the science of boolet casting. So where am I, off in the weeds, or what?
FYI: I have a copy of "The Paper Jacket by Paul Matthews" on order.