I have not had the pleasure of hunting elk with a muzzle loader but always thought if I did I would use one of the 450 grain or heavier bullet in the pic below. (edit one of the 4 on the right) I do have a Knight (several) and I do have these bullets. They shoot great with 77 grains by weight of T7 ffg and a cardboard wad between the bullet and the powder and lube on the bullet. I have not pursued additional load development because I have doubts about me hunting elk in the future.
The bullet is made by Mr Hollowpoint and he has a web sight. He will size them to your specs and I requested .503. Our member Ron has shot them in his expansion tests and those videos are available here.
I like this bullet because it should have a slightly better BC than a lot of lead. A little help anyway for longer shots.
Personally with heavy lead I think if you can hit it you can kill it. I just checked and if assigned a BC of .2 and a velocity of 1450 fps then you will still have 800 fps velocity at 500 yards. I think its going to require something more than a baseball glove to stop that bullet. Lots of theory here. Good luck and kill one for me.
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