id venture to say maybe it was th ebullet weight and the twist of the barrel liking it a little better......my mauser liked 165 gr corelokts.....i hated their performance so i quit hunting with them.....but it liked them pretty good...pretty wierd...the cheap ammo shoots better......but i didnt like the performance and i dont care how good the shot is...the bullet falling apart wont give you a good kill...