Hey Fellas,

New Guy here, love this forum from what I've seen so far...

Would any of you have some load suggestions for 500gr and 550gr bullets? I'm new to the .458 Win Mag and am working up a load for it. I've been experimenting with various bullets and powders and am having trouble with cast bullets in particular in my #1 - very eratic with cast bullets. With jacketed I've had much better luck (Woodleigh 550gr SN), so not sure if perhaps this rifle just "doesn't like cast bullets" or if my .460" bore is the problem cuz most cast bullets are sized .458" or .459"...

Elmer Keith always said "exact groove diameter" gives the best accuracy and I know he was rarely far off the mark with his advice.

Any advice on cast bullets or accuracy problems is appreciated. (Is the forearm pressure the problem perhaps??)

458RugerNo1-
Have you thought about a full case (maybe with a bit of comrpession (about 0.125" or so) of Swiss 1.5fg black powder? Just to try something different.

Brent

I forgot! Also had one in 223 which shot in the .3" 's

The 458 Winnie has a very long throat. So it is damned near impossible to get good cast bullet accuracy out of it. I know, I have tried. At around 1200 fps I could get 4" groups @ 100 yards. That is a mighty reduced load and probably about what you would get with a case full of 1.5 fg powder.

My favorite "plinking/deer" load was:

Federal or Winchester brass
CCI 200 primer
67 - 72 grains of IMR3031
Remington 405 grain Flat point (crimped on first cannelure)
Muzzle velocities ranges from 2100 to 2240 as I recall.
Accuracy was a good as it got ~ 2" in the M70 and 1.5" in the Mauser.

You can load it down to about 62-63 grains if you crimp on the first cannelure, lower than that and I got some hang fires. If you crimp on the second cannelure you can drop powder charges well down into the 50s. The short COL associated with crimping in the second cannelure is an issue with a magazine rifle, but in a Ruger No1 should pose no other issue than increasing you throat length, which will probably adversely effect both velocity and accuracy.

I can dig up more load data when I get home if you like, send me a PM.

Scott

Since the 458 WinMag has a limited case capacity, you have to treat it like a longer 45-70. RE-7 seems to work out well with my older model 77. As far as using cast bullets, I've found that using .460" gave me better results. You have to just call around to the outfits to see if they'll send you unsized 458 bullets. I've also used the bigger 45 Colt/454 cast bullets that were unsized with some good results with Unique. There are a lot of options but requires a lot of hair pulling before you find that 1 or 2 loads that the rifle will like. Try posting on the Cast Bullets section and see if somebody can help you further.