I have found that most in line ML's shoot best with 75-100 of volumetric measure. I have also found that shooting the Sabots they like the pelleted powders verses using loose grain powder. This what I have experienced, but isn't the rule. I have seen guys trying to use 100-120 grains and have poor accuracy. I tell them to drop to 75-80 grains and their groups come right together. It is a serious chunk of lead you are going to be slinging, so keeping it right around 1650-1900fps is going to wreak havoc on the inerds of deer when you smack. Not to mention it only weighs 90#. The bullet is half it's weight already!
I all seriousness, I hope this helps.
If you want to shoot round ball (which I know is not suggested by the manufacturer, but can be done) use a .015" patch, Goex 3F powder, and a Hornady .490" round ball. Loose powder with the round ball works really well. This would be great practice for off season shooting and practice. I can attest to the effectiveness of 50grn of 3F within 100yds on a whitetail with a round ball. You may want to look at your local laws and see if you can use smokeless powder in your muzzle loader. The ML-II I believe are capable of using smokeless, but make sure you have the right model. One is black powder specific, while the other can handle both types of powder. If you are allowed to use smokeless powder in your muzzle loader, then I can't help ya there.
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