I have 2 large-game muzzle-loaders currently--a Thompson-Center Hawken in .54" caliber with OEM 1-48" twist barrel for Maxi Balls and a Green Mountain swap barrel in 1-66" for PRB's.
The Hawken is a PRB-only gun as far as I'm concerned. Accuracy is far superior with PRBs to that of the Maxi-Balls. In my barrel, accuracy stayed good all the way to 110 grains, but that crescent buttplate on the T/C exacts a toll on the user's shoulder once past 100 grains behind a 280 grain PRB. No mas, por favor!
The other rifle is a Spanish-made Zouave-pattern in 58 caliber with 1-72" shallow-groove twist. I have fired traditional Minie balls through it using musket caps and 60 grains of Goex Flaming Dirt. Recoil isn't strident, accuracy is about like deer slugs in a rifle-sighted Rem-870.......five go into about 3" at 50 yards. Velocity runs about 900-925 FPS; 60 grains of FFg was the service load using the Minie balls during the War Of Northern Aggression.
Patched round balls elevate performance markedly with this rifle. A .570" RB patched with .015" ticking soaked in melted SPG atop 80 grains of Goex F/D will run about 1275-1300 FPS and shoot into 1-1/4" to 1-1/2" at 50 yards. Accuarcy degrades and recoil increased at 90-100 grain charge weights. 80 grains is its sweet spot, but is by no means a maximum load.
I still have Swiss and KIK powders on hand. These burn cleaner and provide a bit more energy per a given charge than does Goex. Musket caps are all I use for hunting loads.
To conclude--I have seen two massive mule deer in California during my lifetime. The first occurred during deer season 1983 at 0400 hours. I was on duty driving a patrol unit up Old Banning-Idyllwild Road. This HUGE beast stepped out into view that late October early morning, and had a couple does with him. We looked at each other for a half-minute before the 3 critters walked out of my headlights on the curve. Remarkable.
The next monster California buck showed himself right at shooting light on an early November morning while I was afield, 400-450 yards away across Cienega Seca in the Santa Ana River's headwaters area. If I had my scoped Model 70 x 30-06 with me, I would have tried the shot. That season I had committed to taking my deer with ether a magnum revolver or a M/L rifle, and i had both along for the ride this day. What followed was the most sublime, exhausting, and memorable day of deer stalking it has ever been my pleasure to engage in. That wise old buck toyed with me for 11+ hours, staying just out of view and/or shooting range all day. It was the last day of the season as sundown fell; legal shooting time ended 30 minutes later. Job well done, Mr. Muley. That Hawken and my S&W 686 x 4" ended my 1996 deer season with style.
