Yeah, certainly the 44 has the umph to put down a whitetail at that distance. Are you handloading or using factory loads? For the factory stuff, I'd look to wide meplat lead projectiles for the best accuracy and slap. Look at Garrett Cartridges, Cor-Bon and Buffalo Bore for spectacular results. But... you gotta do your part, put the bullet where it counts or it don't count atall.