I would not go over the recommended 120 grains. Some are going way over, then don't know why their gun blows up. They have the potential of a bomb blowing up in their hands. If you need to go faster than 2000 fps, get a center fire. Muzzle loaders are supposed to befor short range. If we start shooting deer out to 300 yds, pretty soon we won't have a special season.