Accurate loads for 458 win. Mag.

[358Scout]

I have a 458 Winchester Mag built on a Remington 700. It has a 24" Bevin King barrel with a 1:14" twist. I have developed loads with Barnes 500gr using 50gr of IMR 3031 which gives me 3/4" groups at 100 yards.

Because of the price I would like to lighten the loads and use 300, 350 or 400gr jacketed bullets used in 45-70 cartridges mostly for target shooting.

My problem is this - I'm getting crappy groups. ( 1.5" - 3" ) I've used 3031, IMR 4895 and Reloader 7. Hornady 350 gr, Speer 350 gr, cast, both wheel weights and x hard both gas checked. Wasted a ton of gas to the range and back
and now dont know where to turn.

Any great recipes?

 

[JasonYuke]

You may not find what you are looking for with light bullets and that twist...I went through the same thing, just bit th ebullet and stuck with 500 gr and BLC2

 

[Boomer]

A good way to beat the cost of shooting a .458 is to choose cast bullets. The velocity possible with a .458 when loaded with a heavy bullet is perfect for the cast bullets and no performance is lost over the expensive premium bullets. MT Chamber's hard cast 480 gr WFN is a fine bullet for both the .458 and the .45/70. IMR 3031 and Winchester 748 are suitable powders for maximum loads and SR-4759 and Unique would be my choice for loads up to 1600 fps. Ken Waters notes that H-4831 will produce a good low velocity load, but you'll have to use much more of it than you would with either 4759 or Unique.