After watching the "Best of the West" hunting show on tv I checked out the gunwerks rifles on there website. They are coming out with a 500 yd. muzzleloader. I did a little calculating and figured a 250 gr. bullet will need to be traveling at 2300 f.p.s. to have enough energy to kill a deer,(thats at the 800 f.p.e. some claim is needed). The bullet would need a .300 b.c.. A 200 gr., .300 b.c. bullet would need to be traveling about 2550 f.p.s. By the looks of the prices on there other 2 rifles it seems it would cost no less than maybe $2500 to purchase. Would you spend the money if you could to obtain those yardages? I would just be more interested in the bullet they come up with. Right now I'm not aware of any muzzy bullets with a b.c. near .30
http://www.gunwerks.com/Products