which caliber gives better long range trajectory? I really like the .54 caliber and I plan to go with that, but my father in law is really partial to his Thompson Center .45 percussion, which he says has a flatter and longer range trajectory.
With roundball rifles, there is not a huge difference in trajectory. They are all 100 to 150 yards rifles, for the most part, in terms of practical accuracy and proformance on game. Shooting conicals, the .45 will have an advantage over a .54 in any practical bullet weight.