this was a great thread, full of whiz and vinegar ! i am sorry i missed it earlier.
in automatic and most sheet metal guns, made para bellum, they arent terribly concerned with trifles like accuracy or primer dent size, they simply want the ammo to fire and not jamb, from the open bolt position.
so evidently, we have found that firing mil-spec 7.62 x 38 surplus or new just won't work too well in a handi and/or requires mechanical changes just to light it off !
a question that begs to be asked is "are any of you shooting military stuff seeing blow by around your cases and out the breech ?"
i'll bet the steel cases release from the chamber walls at much higher pressures than brass cases.
although i understand freds' dislike for the 7.63 x 39, having commie roots and all, i think it would perform quite well with cast bullets using hunting grade brass cases and an upset version of lymans 31141 mold with some sort of gas check !
sg