Sounds like you right on for starting out. I use the Shockwaves 250 grain bullets with the supplied black sabots and fire 100 grains of Pyro Pellets and can group within 2" at 100 yards using a Remington Kleenbore 209 primer. My muzzle velocity was around 1780 fps last time I checked a long time ago. I would start out at 90 grains of powder and gradually go up in 5 grain increments if you use loose powder. My other muzzy does great with same load but using 110 grains of loose Pyrodex. You never know. Most guns work well in that 90-110 range IMO. Good luck and let us know how you do.