Obviously, every rifle will be different. It took me over 130 rounds and three powders before I could get good results from my 300 RUM using Barnes 180 gr. TSX bullets. My load finally settled in at 98.8 gr. of H-1000 with an ave. muzzle velocity of 3430 fps. Definitely at the top end of the scale...but nothing else was working. Rifle is Rem 700 action w/27" Lilja barrel and McMillan stock. Be sure to work up slowly.