458 Win Mag Cast Load Data and Musings

[bobthenailer]

Saeco #020 540 gr fpgc sized @.459 with 50 gr 4831 in my 45/70 has put 25 shots in 2 1/2 inches @ 200 yards. just bump up the powder charge some use Accurate powder data for reference.
I tried all of the usual powders and this gave me the best accuracy, also bullets much over 450 gr may have to be shot @ 200 yards to stablize correctly to obtain the best accuracy

[bosco555]

I know that this is an old thread, but here it goes anyway. I have a ruger M77 bolt action in 458WinMag. I had untold trouble with cast boolits as they would not stabilize and were going all over the joint.

I tried all sorts of powders/GC and different casts, eventually I gave up. However last yest I found that a specific type of cast boolit of 405gr, with only 2 grooves, GC and coated (Westcastings Australia) together with a load of 66gr of Re10x, gives me good accuracy at 2100fps. I have to have that speed according to competition rules (big game).
I can only surmise that too mane grooves on the boolit prevent it from gripping the rifling and stabilizing properly.

Yes, no loose fillings and also while developing that load, it was a punisher shooting from the bench...Rather have a couple of rounds with Mike Tyson..

Next, I need to test Reloader7 as many shooters told me good things about it. Here we go again...Ouch! Also will be trying PC, please see the PD threads...

[Just Duke]

I know that this is an old thread,

We are old men so no problem.

[Just Duke]

I now use 40 grains of IMR 4198 and a 500 grain LEE GC in a Winchester Model 70 Control Round Feed .458 Winchester Magnum.
The recoil is so tolerable that Barbie can shoot a whole box through the gun with no flinching.
I have pics of both of us shooting the gun if anyone wants to see them.
This load and these guns will be our go to load for S. OR Roosevelt Elk in dense Timber.

[Just Duke]

[Changeling]

Barbie's Camoflage is awesome, but her "Outback" hunting shoes need some work, LOL. Great photography, I have shot a friends 458 loaded hot (his sense of humor!) Winchester pre 64 model 70, best I can say is "OUCH".
I really like this post, it shows what can be done with a 458 if one knows what they are doing, thanks Duke.

[Just Duke]

Barbie's Camoflage is awesome, but her "Outback" hunting shoes need some work, LOL. Great photography, I have shot a friends 458 loaded hot (his sense of humor!) Winchester pre 64 model 70, best I can say is "OUCH".
I really like this post, it shows what can be done with a 458 if one knows what they are doing, thanks Duke.

You bet.
We were on our way back from the other house and were also attending a pool party in the vicinity. We had the rifle with us and Barbie asked if we could pull off and break it in as it had never been fired before. So we pulled off and unboxed it and let loose 40 rounds.

[Just Duke]

We both got fat as the picture shows but were working on leaning out.

[300leonidas]

http://www.saami.org/PubResources/CC...r%20Magnum.pdf

This link didn't work anymore but I found the information here:
https://saami.org/wp-content/uploads...sting-Copy.pdf

[300leonidas]

I plan on running this series again with water dropped alloy that is giving me a Brinell of about 18 or better. Don’t want to get into oven heat treating, but if harder continues to be better, may ultimately give it a try. Even if this was the best I could do with these bullets and velocities, these loads will do just fine for hunting anything in the US.

Thank you for all of this great information! I am new to the 458 Win Mag and am trying to work up some cast bullets that will work. If hardness is a vital part of good accuracy, as you suggest, wouldn't linotype lead (BHN ~22) work well?

[Ben_51004]

This is a fun thread! I'm the odd duck with a Remington M700 in .458 WinMag. I inherited this from my father, who found it in a gun shop near Topeka Kansas. It came with a box of ammo with one round missing.... hmmmmm....! Anyway, I loaded up some .458 cast bullets (about 350 grains as I remember, this was about 20 years ago) with some light charge of powder and went to have some fun! Well, fun I had at the range, but those bullets did NOT carry enough lube and I spent quite a bit of time de-leading the barrel. I've been meaning to get the ol' girl out and give her a spin again. I was thinking the Lee hollow-base... it carries plenty of lube! Or, now that I'm somewhat wiser, maybe powder coat them or at least LLA. Now this thread has me wanting to get out to the range....

[Larry Gibson]

Thank you for all of this great information! I am new to the 458 Win Mag and am trying to work up some cast bullets that will work. If hardness is a vital part of good accuracy, as you suggest, wouldn't linotype lead (BHN ~22) work well?

You'll want two things if you intend your 458 to "work" in the range of factory 458 Magnum ammunition. First is a more malleable alloy than straight linotype. Linotype can be a bit too brittle. Use the linotype to make Lyman #2 alloy which will be excellent AC'd or WQ/HT'd. Second is you'll want a GC'd bullet such as the Lyman 457483 (385 - 400 gr) or the Lee 547-500-FN (500 gr). Both bullets will carry sufficient lube. On your own bullets use a soft NRA 50/50 lube or 2500+. White Label makes both.

If you want a plinking bullet, there's not a lot of sense throwing 400 + gr of bullet with each shot or using a GC. Check out NOE and Accurate for a bullet in the 250 - 300 gr weight. Bullseye or Unique will prove very good powders to use to push that bullet at 800 to 1400 fps. I use a 270 gr bullet at 1050 fps.

[Larry Gibson]

Ben 51004

Your lube problem was probably due to a hard wax lube on the commercial cast bullets if those are what you used(?). The Lee 405 HB bullet replicates the original M1873 bullet and is made to carry sufficient lube for BP loads. I suggest the bullet advise I gave to 300leonides for use in your M700 458 Magnum. Those bullets carry sufficient modern lubes such as I mentioned that leading should not be a problem.

[300leonidas]

You'll want two things if you intend your 458 to "work" in the range of factory 458 Magnum ammunition. First is a more malleable alloy than straight linotype. Linotype can be a bit too brittle.

Larry, My question about Linotype was based on paborn's recommendation that the harder the lead the better. I actually did make some from linotype a couple weeks ago and they shot very well. They were also powder coated and did not have gas checks. That doesn't mean Regular Lyman #2 will not shoot well also. I'm going to try that and see.

[300leonidas]

Powder coated bullets made from a Lee 2-Cavity Bullet Mold 459-500, which actually came out to weigh 432 grains using linotype lead. No gas check. This load was with 50 grains of IMR 4198. No fillers in the case. Velocities were 1850, 1850, and 1846 out of my Winchester Model 70. Adding 3 more grains diminished accuracy significantly.

[ShooterAZ]

Nice shooting 300leonidas! If you can find any, Accurate's 5744 is a fantastic cast boolit powder in the 458 Win Mag.

[JWT]

I've got a 1965 Winchester super grade model 70 that I want to dedicate to cast. Lots of good info here. Has anyone tried PP?

[300leonidas]

i've got a 1965 winchester super grade model 70 that i want to dedicate to cast. Lots of good info here. Has anyone tried pp?

pp?

[ShooterAZ]

PP = Paper Patching.

[charlie b]

I'd go to the BPCR folks. They know PP.

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