Greener... first off welcome to the forum. As for your rifle.. a good one for sure. One thing you will come to learn fast is even though you have a rifle able to handle 150 grains of powder, that does not mean you have to shoot that. The beauty of a muzzleloader is they can be loaded light or heavy depending on the bullet and distance you want to shoot. All a 150 grain charge usually does is pound the devil out of your shoulder, produce a bad flinch in some cases, accuracy is not as good, and puts a lot of stress on you, your rifle and your pocket book buying all the powder. Some of the rifles will not even burn all that powder up before it gets out the barrel.

You are going to find your best accuracy in the 80-100 grain range on the FFg powder scale. Because it is a .45 caliber you might want to go with an FFFg powder which was often the case with the sidelocks. It burns a little cleaner but also rememeber it produced a little more barrel pressure. Approx 15% more in some cases. A rule of thumb to follow is if you were loading 100 grains of FFg then 85 grains of FFFg would be very close to that. Start testing the projectile with a low charge and work up in 5 grain amounts until the group goes out the window. Of course this is harder to do if shooting pellets. When shooting pellets stick to 2 fifty grains or a fifty and a thirty grain pellet. I shoot loose myself. Saves money and I do not have to worry about pellets.

Your rifle was made to shoot powerbelts for the most part. In fact the diameter of the bore was made to fit a powerbelt. Many people find they get better accuracy with a fowled barrel. You will need to experiment. To fowl the barrel drop 20 grains of powder down in, push a cotton patch on top of the load making sure it is seated all the way down to the breech and then shoot it off. Now run a swab through the barrel of alcohol and you are fowled. The problem with fowling the barrel is whether you shoot anything that day or not, you have to clean the rifle.. Some people also fill the button with lube for the first shot instead of fowling the barrel. You will only know how the rifle behaves when you try some of the things mentioned.

I can understand your liking the idea of a full blown conical out of the rifle. Why drop to a .40 or .357 caliber bullet when you can shoot a .45 caliber. The powerbelts are a good answer here. Pull the plastic button off the back of them first and then grease the lead spike of the conical. Replace the button and load as normal. This will help the powerbelt shed the button faster which will increase your accuracy. Put a .45 caliber hole through the vitals of any animal and they do not go too far (we hope).

If you want better penetration then go with the aero tip powerbelts. If you want to shoot thin skinned animals and blow a big hole in them you want the hollow points. A word of caution, some of the powerbelts, especially the hollow points, will not produce an exit hole which if the animal runs off can make tracking harder. I personally like the aero tips but my Staghorn likes the hollow points for accuracy.

If you want to see how sabots will shoot, get some of the name brand sabots and try them in your rifle. Thompson Center, Barnes Expanders, Hornady, Knights... some might load real hard some might not. Also the powder charge depending on the sabot will vary, so what works good for one will not be the case for all. You have to experiment. Sabot brand can make a real difference here. My CVA likes Harvester sabots.

Be sure and swab between shots when at all possible. Firing charges created a crud ring in the breech and you must make sure you remove that so you do not make a mistake of loading only to the crud ring. If you were to fire like that you could ring the barrel. I make a swab solution of 50/50 isopropyl alcohol and car windshield washer fluid. Work a damp patch in short strokes from the muzzle down to the breech and back up. Turn the patch over and repeat that with the other side. Now run a dry patch or two through the barrel and your ready to load again. You should feel a smooth barrel with the dry patch.

Also swabbing the barrel before you load the first time will remove any oil from the barrel and produce a better ignition for you. For the sake of yourself and your rifle, get a range rod to load and clean the rifle with. Make it at least 4 inches longer then the barrel. I like the 32" T/C rugged rod but there are better ones out there. Save your rifle ramrod for loading in the field should you ever need a second shot, which you will not because we make the first one count....... right?

Good luck with your rifle.. Keep us posted.