CVA make a sold lead Power-Belt bullet in 295 grain, I've used it in my .50 cal Optima and it has performed good.

I like the .45 mostly cause I have a good assortment of .45 caliber molds from 200 up to 550 grains. Sized to .451, they all work from my TC and Whitworth rifles. The Whitworth likes the heavier bullets and the TC shoots an elk load of 130gr. triple 7 behind a 385 gr flatpoint. That load exceeds the "power" of the old .45-90 which was considered big elk medicine in the day. In a conical shooting rifle .45 is very nice.

If you are hunting deer only, a .45 lead pistol bullet will work, but I'd prefer a .50 with a heavy bullet for elk or moose. Some states requirte at least .50 caliber for elk hunting.

I would go with a .50 cal. I have .40, 45, 50, 54, 62 and 76 cal muzzleloaders. The 45 is okay for deer, and yes you can shoot heavy bullets and heavy charges of powder for knock down power and distance but a .50 with a conical, maxi ball or roundball and various charges of powder will do most anything you want. Like said earlier, most states have min. calibers for elk. I have taken many whitetail and mulie with 50 roundball. You can plink with a roundball and 50 grns of powder or hunt with a roundball and 90-100 grn of powder. They make many power belt style bullets and sabots for a 50 and not very many for a 45 anymore.
I like my .50's and .54's. You just get a little bigger dia. projectile and weight and depending on the barrel/brand of muzzleloader you can shoot roundball or bullet with sabot or like the Hornady Great Plains bullet without the sabot. Just my opinion and it took me 30 years of shooting smokepoles to come to that conclusion.
Good luck and shoot straight.

Mike

I dont have one yet. I'm trying to decide if I wnat a .45 or a .50. I want\have to shoot a conical all lead bullet due to regulations in Montana.

If I can get a modern .45 calibre muzzleloader that will shoot lower weight conicals (pistol bullets) with a 150 grain charge of powder I will probably go that route. If not I'll try a .50 cal.