The nice thing about us traditional black powder shooters is that we can tailor our loads. So although a deer load in that .50 might be as John Wayne pointed out in True Grit when Glen Campbell shot the turkey with a Sharps..., "Too much gun". Yet you can drop down that powder charge to something accurate at 50 yards but not at a velocity to whack through and through on a whitetail..., and not blow the turkey up. I will have to check the state regs and see if turkey, unlike deer, has a minimum black powder load. Deer the minimum in Maryland is 60 grains of powder, but with my .40 I'd prefer about 35-40 grains against a gobbler.
LD