whitesmoke, ive got a t/c renegade .54. havent ever shot conicals out of it, i actually purchased it so that i could shoot roundballs. at 50 yards it shoots roundballs pretty well w/ 90-100 grains 2f blackpowder. actually, i seemed to be getting more strays as i went up in the powder charge, so 90 grains was the load i settled on. if i remember correctly, i was getting 2-3" 5-shot groups (at 50 yds). that's with the crude t/c sights.
the renegade has the same 1-48" twist as the deerstalker, and i believe that it will shoot conicals very well. i'd try the t/c maxi-balls @ 430 grains. if you are set up for lead casting, that'll be a lot cheaper. i shoot roundballs in mine cause it has a steel buttplate and i don't find it comfortable to shoot with heavy conicals. the deerstalker has a recoil bad, tho . . .
with conicals i'd start with a slightly lower powder charge, say 70 or 80 grains 2F, and then work your way up until you find the charge that groups best. not sure about the deerstalker, but my renegade will take a full 120 grain charge of 2f and a 430 grain maxi-ball. that packs a wallop on both ends! i'd also experiment with 3f, but keep in mind that the maximum loads listed for the gun are for 2f (3f produces more pressure).
btw, i just ordered a deerstalker myself
. ive been wanting a flintlock for some time now, and the deerstalker is the cheapest good-quality flintlock available for someone like me who just wants to give rocklocks a try. i ordered one of the "reconditioned" deerstalkers from lyman's webpage fer $230.