Home Forums Hunting & Shooting Express Rifles and Big Bores Only The great 458 Winchester. Everyone should own one at least once

A closer look at the sectioned Peterson brass:

Other brass to turn into .458 WM:

404-gr Shock Hammer review:

If the Peterson brass formed to .458 WinMag comes out with smaller case capacity than any other I have measured,
seating the bullet out by 0.100" will add 4.166 grains of water capacity for each step.
With Winchester, Hornady, Remington and Federal brass, case capacity is 94-95 grains.
Norma brass is 99-100 grains.
Could Peterson be as small as 90-91 grains ?
Even if so, equivalent net case capacity roughly:
Norma: ~3.280" COL
W-W, R-P, Hornady, Federal: ~3.380"
Peterson: ~3.480"

Or use them all with same COL and use less of same powder in the Peterson ...
more velocity per grain of powder would come from the Peterson.
Less recoil for velocity achieved.
Less is more with the .458 WinMag.
That is why the Lottites flinch so much.

I'm shooting the 404 grain Shock Hammer @ 3.383" COAL in Norma brass Federal 215 primer ahead if 85 grains of AA2230 new manufactured powder for 2523 FPS. This load may be a bit over SAAMI MAP, but has worked fine in my rifle with repeated loads in the same bras

Sir John,
Good .458 WM+ load.
Probably less than SAAMI MAP for the .458 Lott, so it is less than R.I.P. MAP for the .458 WM+.
When I get the Peterson brass fired, I will check the gross water capacity,
once-fired and not re-sized, and trimmed to 2.500" or corrected by calculation if short, as is customary for my comparisons.
The QuickLOAD default case capacities use that sort of value.
If default .458 WM brass is 95.0 grains,
then NORMA brass would be 100.0 grains.
Peterson brass TBD.

I have some dummy cartridges loaded for M70 Super Express Classic. 404 Shock Hammer, COL 3.3395" seems reliable function. Though, I am going to seat somewhere between there and slightly less. This magazine box is unaltered and seems a bit short, particularly at the top. I will investigate further, but good enough for the present.

I may try an H&H magazine box or another of the same type. But, I think 2350 fps + will be comfortably achievable as is with the 22" barrel. I am going to start with either 74 or 75 grains of A2230 using virgin WW brass.

The Interarms Mark X that I have will take a COAL that will not fit in the classic Super Express's magazine box.

Sounds like a good plan, Sir Larry.
You'll get more velocity per grain of powder with the 404-gr Shock Hammer seated like that
than what Speer shows here:



Weird is all I can say about the short M70 Super Express mag box.
Could it be one of those Monday or Friday rifles circa Connecticut closing in 2006 ?
Maybe one of the depressed employees grabbed the wrong box in assembly ?
Close, but no cigar on that one ?

Speaking of mag boxes and assembly, my FN Mauser with 24", 1:10" twist Pac-Nor is finally
moving in the one-man assembly line at Hilltop Gun Shop and Spa for Wayward Rifles.
Gunsmith messaged a blurry photo yesterday asking if this was OK:



I said it was swell, looks like a Westley Richards front sight ramp placement. Stylish.
He used the barrel sights that came off of my 19.75"-barreled .458 B&M+, with No. 4 sporter Pac-Nor, 1:10" twist,
when I had it cut down to 16.9" barrel length.
That is where the old front sight fitted on a No. 5 sporter Pac-Nor cut to 24". Sweet.
So I will eventually have a 24" fast twist .458 WinMag to compare to a same maker/twist 16.9" barrel on the .458 B&M+.
Mag box on the .458 WinMag is a Sunny Hill that is about 3.470" inside length, IIRC, drop box.
Should be interesting.
Both can share the same suppressor or muzzle brakes.
One or the other might be better for subsonic work or VLD supersonic plinking,
will see eventually, heh-heh-heh.

Save expensive bullets for serious work.
Plink and pot-shoot with these duffers:



Remember that the 300-gr Sierra Pro-Hunter hollow point vaporizes at 2800 fps muzzle exit.

Having to make .458 WinMag brass out of "wildcat tubes" got me thinking about the .458 WinRuger again.
I never did it justice since it was done half-heartedly to clean up a .458 WinMag chamber that had factory chatter rings in the chamber.
It may need a second look to make use of the Hornady-Ruger brass lying about.
A review, comments welcome:

I cannot fully explain the differences between my .458 WinMag results, compared to the .458 WinRuger.
Maybe a second trial with formed brass would allow the .458 WinRuger to handle more AA-2230 ?
Maybe it is a result of the one rifle I have tried in .458 WinRuger (Whitworth Mark X) having some idiosyncracy?
It was put together by re-chambering the .458 WinMag with a Ruger-body reamer and a .458 Lott reamer for neck, leaving the remnant .458 WinMag throat.
I am quite certain the unimproved Ruger-body is sufficient, producing adequate shoulder.
Neck length of .375" might be criticized as relatively better than what is on a .500 Jeffery.
The .416 Ruger neck length is .339" and it does well.





The effective throat on my prototype .458 WinRuger is only 0.080" shorter than on the .458 WinMag,
due to the brass difference: 2.580" max versus 2.500" max.
I need a new barrel and a purpose-built reamer to be fair to the .458 WinRuger.





Wildcatter264 is our newest Four-Five-Eight Fellow, Knight of the Square Table, Sir Khulu (Ndebele for "old man") might be interested in doing this,
to add to his experience with a 404/.416 Ruger, .458 WinMag, 460 G&A, .450 Rigby, etc.
Most old men usually settle on the .458 WinMag, after the new wears off the others.
But a .458/.416 Ruger with a .458 WinMag throat makes good enough sense.
Sir Khulu has mentioned having JES do a .458 re-bore of a .416 Ruger.
Shazam !

Wonder how CFE223 would do in the WinRuger? Might require a heavier bullet seated to 3.6" to be efficient...

The Ruger Hawkeye Alaskan with the 20” bbl is currently at JES undergoing rebore to 458. Soon as it’s back it’ll be pressed into experimental service to determine feasibility of making the Zim trip in July. Reports on load development will follow then, using the CEB BBW #13 450 & 500 grain monolithic solids.

Agree with Sir Ron’s capacity measurements for the 458 Ruger preliminarily formed from Ruger 375-Basic brass but not yet fireformed. I use BL C-2 as the volume measuring medium, as its specific density is very close to water equivalence and doing so saves wet case dry outs. Based on my tests with the Hornady brass which I use for this class of cartridge - 375, 404, 458 based on the Ruger case - capacity measured to base of a seated bullet - not to the shoulder-neck junction or mouth of case - with the BBW #13 450 grain 87.0 grains and with the 500 grain it’s 81.0 grains. Both are based on COAL = 3.4” limited by the Hawkeye’s magazine and bullet groove crimp locations. These parameters allow use of the unmodified Hawkeye magazine box and based on preliminary tests in a Hawkeye African, buttery smooth feeding. Capacity is 3 down and 1 in the chamber. - the classic 4 quick shots, if needed in the herds.

Most of the experimentation will be focused on defining the appropriate burning rate powders to achieve 100% load density with little to no compression. Will probably start with RL-17 and H-4350. Both work well in the 404-375 Ruger but may prove slow with the 458 Ruger. RL-16 and possibly IMR 4451 may be candidates if faster burning rates are required.

Good to see Sir Khulu planning a .458 Safari.

Anything .458 caliber is cool IMHO, from .45-70 and SOCOM to .460 G&A and Weatherby.
Always interesting to hear how which bullet at what MV did at what range to what critter.

IMR-4451: I have not tried it, but might have put some in the powder locker.
Or was that IMR-4166 ? Would have to dig to see.
IIRC, IMR-4451 burn rate is a tad slower than IMR-4350.
and IMR-4166 is a tad slower than IMR-4895, but faster than IMR-4064.
But both are Enduron powders that cut copper fouling and have good temperature insensitivity.

IMR-8208 XBR is slightly faster than IMR-4895, super-short-grained,
tops in temperature insensitivity, and I can vouch for a lot of good load data with that
in .458 B&M, .458 WinMag, and .458 Lott,
pressure tested and chronographed by Michael McCourry in South Carolina.
That would be my next choice to test in the .458/.416 Ruger.

As suggested by Sir Bevan:
Another good one to consider is CFE 223, ball powder, good for +2200 fps in the .458 WinMag with 500-grainers,
at 3.340" COL or less and 60,000 psi or less.
Ought to be great with heavy bullets in the .458/.416 Ruger.

Peterson Cartridge Company H&H-Belted Wildcat Tube
fire-formed to .458 Winchester Magnum,
with a delightful, low-recoiling, very uniform starting load for the .458 WM+:



A Ruger M77 Mk II with 25" Shilen, 1:14"-twist barrel, was used.
Scope was a Nikon 3-9x40mm SlugHunter with 75-yard parallax, in medium-height Ruger extension rings:



Not quite ready for King of Two Mile, but this is the brass to use for the competition.
When I get the 1:10" twist FN Mauser out of the spa, some experimenting with supersonic VLD heavy bullets is in order.
I got a taller tripod and now I can chronograph at the 100-yard public range position,
where the ground drops off more in front of the bench,
as long as I hang a sandbag under the tripod to keep the wind from blowing it over.

Good stuff, Sir Ron, and thanks!

Bob
www.bigbores.ca

Excellent research!

Sir Bob and Sir Larry,
Asante-sana-sana.
Peterson brass will definitely be my pick for King of Too Far shooting with the .458 WinMag.
10-pound weight limit and 3-pound trigger rule.
We'll put those contestants from King of Two Mile to shame.
They are invited to the match, bring on the .375 Chey-Tac, but they have to make the weight limits.
An FN Mauser .458 WinMag (still at the spa) will be my entry.

Sir Khulu is building a .458 WM Hawkeye.
It will be backup for his .460 G&A safari.
He will be leaving his .458 WM ammo with his wise PH who favors a .458 WM.
All the ammo will all be elephant-adequate, I am sure.

That fire forming group ain't too shabby!