You do what everyone needs to do... and that is take the time and experiment with loads to find out what works for a particular smokegun. You actually go the extra mile and post. I believe too many center fire shooters or beginners who try muzzleloading expect too much on the bench the first time they stuff something down the barrel and "let-'er-fly". There are no pre-packaged "factory ammo loads" at WalMart... they need to realize they have to make the loads up themselves
!
Here's a flash-back story that comes to mind, so please bear with me. I once met a rookie at the range who had a collection a .50 caliber muzzleloaders of various qualities spead-out all over the benchs(you know... you've see it before). It drove me insane when he said he didn't like to shoot "that one" because: "I can't get that piece-of-junk to shoot...I guess you get what you pay for". Well, as I stared at the "out-of-the box" Traditions rifle, I was so-o-o-o tempted by the devil
to first say to him: "if you want to sell that piece of junk, I'll take it off your hands for you". But my better sportman half won. I ended-up getting 6 pounds of elk hamburg from him in payment for getting his Traditions "piece-of-junk" to shoot.
He couldn't put any of his smokepoles down from then on. He was on the bench ALL the time experimenting. (I don't think his wife particularly cared for me for what I turned him into ... I think his wife was ready to divorce him!...
)