458 Win Mag

[Cheech]

Hey Guys, I need some help. I have a 458 Win Mag built on a Mauser action and have some Barnes 500 and 600 gr boolits and I have reloading data for these. I just purchased some 550 and 720 gr cast WFNGC boolits and have no data for them. I've searched the net to no avail. Any suggestions?

[Johnw...ski]

I have one built on a 1917 Enfield action, I plan to use the 462560 boolit from a group buy, it weighs around 545 gr., in it next and will start out with lighter 500 gr. load data for IMR3031 or IMR4064 powder. I have no problem interpolating loads for odd weight boolits and usually work up the load untill I start getting leading. The most accurate loads usually happen just before the leading start.
The .458 will really hurt shooting from a bench with these heavy boolits so you may have to end up finding a load you are comfortable shooting and that prints well at whatever range you are using.

I won't even venture a guess as to a load for your 720 gr boolits but they should be very suitable if your rifle has the standard 1 in 14" twist.

John