P-Wolf is corect, the internal structure of the bullet has alot to do with what is safe in one gun and not in another.. as the explosion occurs some bullets will physically react differently that other bullets, this core and % of ingrediants are different also it's bearing surface, how much metal actually touchks the barrel and alot of other physical conditions ALL affect and effect pressure...plus the individual characteristics of each gun enters into the equations...I always start low for a few shots and see and feel what the ejected cartridge is like, I myself use only coated bullets, Moly and most of the time DANZAC, I'm finding that I can take things alot higher than what is printed, but WHY, it really serves no purpose other than flattening the trajectory.. it wears the throat and is hard on cases.. lately, it seems that once I get one to reach 3000 fps, that's enough, no animal can survive a chest hit at that velocity and hit with a great bullet... I use only Nosler Partitions and Barnes X-bullets.. I see no reason for anything else....