[Jeff Higgins]

Hmmm... You are up against the steepest learning curve in the firearms world, and hindered with time constraints that will make this all the more challenging for you. Let me tell you what I would do (and why), for what it's worth.

Forget about those bullets. They don't carry any lubrication whatsoever. No lube + black powder or Pyrodex = very poor shooting and an inability to reload a dirty bore in very few rounds, if not after the very first round.

The lubricant in black powder (I'll use that term for brevity - just assume I'm including Pyrodex and other substitutes when I say it) serves two purposes. First and foremost is to keep the fouling soft; preventing leading is a secondary function. The vaporized lube mixes with the powder fouling left in the bore to keep it soft enough to push the next bullet down bore. Without lube, you will get no more than a couple of shots without swabbing the bore. The fouling will build that quickly, preventing the next bullet from going down bore, much less shooting accurately if you do manage to hammer it down.

That slow 1:48 twist will have no trouble stabilizing a 295 grain bullet in .50 caliber. That is actually extremely light for this caliber. Slower twists stabilize lighter bullets quite well, with the extreme being something like my .50 flintlock round ball rifle with its 1:72" twist. Longer, heavier bullets demand a faster twist. The 1:48 of the T/C is actually optimized for their 375 grain Maxi-Ball, which it shoots exceedingly well.

That Maxi-Ball carries a lot of lube. I cannot overstate the importance of that. It is a very accurate bullet, and it's shape makes for fantastic terminal ballistics. It has a very sharp front shoulder that will cut, rather than punch a hole. You will note is has no "patch", which is actually a misnomer on the Powerbelt, where the plastic cup serves as a gas check, not a "patch". We do not patch bullets in muzzle loaders, we patch round balls. Huge difference. We actually want the plain lead base of the bullet exposed to the black powder upon ignition, so that the bullet obturates and fills the bore and rifling. This plastic gas check will keep it from doing that, resulting in leading and inaccuracy.

Anyway, if it were me, I would buy some T/C Maxi-Balls on the way to the range tomorrow. Shoot them alongside the Powerbelts and see which is easier to keep loading and is more accurate. I would load 100 grains of your Pyrodex FFg under either. Light loads with heavy, plain based bullets do not work in muzzle loaders. You really have to kick them in the ass to get them to obturate, which is critical to accuracy. Don't be shy - load it up. Wear a recoil pad.

If nothing else, hunt with the .490" round ball over 100 grains of powder. Patch it with .015 thick prelubed patches. I guarantee you will not find a more accurate load for that rifle. That, and round balls have been killing white tails for literally hundreds of years. They work.