^^^^^^ This!!!
There are so many nuances to shooting projectiles at game via muzzle loaders... I try to give advice that works and simplifies the problem. To me, that answer has always been to use Sabots and Jacketed Hollow Points from a reputable manufacture. That advice is legal in 48 states and Canada. Jacketed handgun bullets fired from sabots just work, and work with every choice of powder.
But it isn't legal every where, and for some that generic recipe is hard to load (probably due to choice of sabot/bore/projectile diameter, dexterity, hand-strength, tools, techniques, perception, etc)... but it does seem to simplify the problem overall and yield consistent results... both on loading, shooting, and terminal performance in game... in most rifles.
Alas, there is always freedom of choice, and some chose not to use Sabots/Jacketed handgun bullets. And I support that.
I do -hope- to get my hands on the Hornady Bore Drivers, and I -hope- that they become a simple effective no sabot/jacked hand gun bullet solution, that is easy to load/use (for those who don't like or legally cannot use sabots), and effective on game under most every variable shooters can throw at them. (ie also seals well enough to be reliable with BH209, and has great terminal performance at high & low speed... hitting bone eary/late on its ride through the game animal... etc).
Bottom line for me, is that I cannot recommend a projectile to customers when it has large performance realms that are lacking... just because its easy to load and readily available doesn't make it the best choice... though it may be the best choice of what you have available.
my .02USD
Tom