You are doing the right thing, asking about before buying...Many buy a rifle made for one type projectile and then can't understand why they can't shoot another...

As Cay mentioned, 150 yards is a good poke at game with open sights...If I were shooting at Redcoats at 150, I could pull it off, with a deer 125 is my max with my .54...

Now...I only shoot round balls and I cast my own...I've killed about 30 deer with the .54 and a round ball and another 25 or so with a .45 and round ball...My younger brother has a .50 T/C Hawken and has taken several deer with 90gr and a Buffalo Bullet...Frankly, I can't tell that the big conical has any advantage over a .530 ball...It might when you move up to elk, but for deer a round ball into the lungs drops a deer as well as anything that I've seen...