The “458 Winchester Magnum, all the cartridge you’ll ever need” thread

The CEB Safari Solid #13, 325 grain .458 is poster child for design and construction.
I think there is a chap on this forum that give the field results of this bullet, on an elephant out of his buddy's 450 Nitro. Amazing bullet. Who the heck would have thought a 325 grain .458 bullet could perform as such ?? Though the tests certainly indicated the probable outcome.
 
Hello Slyfox,
Is the rifle not marked as a "450 Ackley Magnum" ?
That is the one we think of usually.
It came along after James Watts started it all with his ".450 Watts Magnum," shooting first in 1949.
Watts visited Ackley and Buhmiller, looking for a barrel early on in his dreaming stage.
It does seem Watts beat both of them to the .450-bore on the 2.85"-length H&H Magnum case.

The .450 Watts Magnum has a straight, belted case, no shoulder, and is 0.050" longer than the .458 Lott wildcat latecomer (1971).

The .450 Ackley Magnum had a 2.85" belted H&H case length also, but had a tiny shoulder located at 2.407" from the base face of the brass case.
Shoulder hemi-angle angle was 20* (cone angle 40*).
Shoulder was 0.503" diameter at 2.407" length.
Neck-1 was 0.487" diameter at 2.429" length.
Neck-2 (case mouth) was 0.486" diameter at 2.850" maximum brass length.

If you have a .450 Ackley Magnum, it really would be best to get the proper handloading dies and some basic cylindrical H&H Magnum brass to size down and shoot, and some properly headstamped brass for Africa. And the rifle needs to be engraved/stamped properly as to chambering/cartridge on the barrel.
The .450 Ackley Magnum is well known and bragged about often by magnificent author Terry Wieland. Proper brass and dies should not be too hard to find. Google away.


I have a .450 Barnes Supreme by Fred N. Barnes, from the 1950s, which is very similar to the .450 Ackley Magnum. Barnes used both Brevex and 1917 Enfield actions for the Barnes Supreme line of proprietary cartridges he offerred.
Long brass, tiny shoulder, load data would be interchangeable.
I also have a .416 Barnes Supreme, another one from the 1950s.
Both of my Barnes Supremes were built on Whitworth MK X actions in 1987, just before Remington came out with the .416 RemMag, boo-hoo.

Watts also did a 2.5" .450 Watts Short before the .458 Winchester Magnum was released to the public in 1956, after James Watts "released " it to Winchester in the year 1954 or before.

Fred N. Barnes was offering his proprietary 450 B-J Express (Barnes-Johnson) in a lineup of "short magnum" cartridges from 7mm to .458 caliber, in the early 1950s.
He claimed his 450 B-J Express was being chambered and rifles sold "several years before Winchester added the .458 to their line."
The B-J express line all had 2.5" belted H&H Magnum ("short magnum") cases with the case body length to shoulder being 2.125", shoulder diameter 0.500", shoulder hemi-angle 35*.
He said in his March 15, 1958 pamphlet:
"450 B-J Express
The most powerful of the B-J Line. Shoots a 500 gr. bullet at 2200 f.s. Works perfectly in any standard length action. Rifles chambered for this cartridge will also shoot the new .458 Winchester factory cartridge.
While this is a so-called improved version of the .458 Winchester we chambered rifles for the .450 B-J several years before Winchester added the .458 to their line."

Seems Fred N. Barnes might have given Winchester ideas about the .338 WinMag and .264 WinMag too.

So when you say "improved .458" it stirs up thoughts of something other than the .450 Ackley Magnum.
Most likely it is a .450 Ackley Magnum if built on a 1917 Enfield and has a +3.6" magazine box internal length.
Mind your P's and Q's and get a chamber cast if any questions.
Firing a factory .458 Lott cartridge in your rifle to get a short-necked version of the .450 Ackley Magnum would be a sort of chamber cast, in brass.
An actual chamber cast would tell you more about the throat.
Lacking that, check the throat length with dummy cartridges using .458 Lott brass before shooting it.

Riflecrank
Sorry I missed your response.
I just bought this rifle at a local auction. The auctioneer called the gun collector and he said his father or grandfather bought this from PO Ackley and it’s a 458 Ackley improved this past weekend. I took the stock off thinking I’d see some markings and there’s zero markings on the barrel that indicate what it is , so that has me rightfully concerned to try to put a bullet off in it based on what this gentleman said your advice is much appreciated. Thank you.
 
Hello Slyfox,
Is the rifle not marked as a "450 Ackley Magnum" ?
That is the one we think of usually.
It came along after James Watts started it all with his ".450 Watts Magnum," shooting first in 1949.
Watts visited Ackley and Buhmiller, looking for a barrel early on in his dreaming stage.
It does seem Watts beat both of them to the .450-bore on the 2.85"-length H&H Magnum case.

The .450 Watts Magnum has a straight, belted case, no shoulder, and is 0.050" longer than the .458 Lott wildcat latecomer (1971).

The .450 Ackley Magnum had a 2.85" belted H&H case length also, but had a tiny shoulder located at 2.407" from the base face of the brass case.
Shoulder hemi-angle angle was 20* (cone angle 40*).
Shoulder was 0.503" diameter at 2.407" length.
Neck-1 was 0.487" diameter at 2.429" length.
Neck-2 (case mouth) was 0.486" diameter at 2.850" maximum brass length.

If you have a .450 Ackley Magnum, it really would be best to get the proper handloading dies and some basic cylindrical H&H Magnum brass to size down and shoot, and some properly headstamped brass for Africa. And the rifle needs to be engraved/stamped properly as to chambering/cartridge on the barrel.
The .450 Ackley Magnum is well known and bragged about often by magnificent author Terry Wieland. Proper brass and dies should not be too hard to find. Google away.


I have a .450 Barnes Supreme by Fred N. Barnes, from the 1950s, which is very similar to the .450 Ackley Magnum. Barnes used both Brevex and 1917 Enfield actions for the Barnes Supreme line of proprietary cartridges he offerred.
Long brass, tiny shoulder, load data would be interchangeable.
I also have a .416 Barnes Supreme, another one from the 1950s.
Both of my Barnes Supremes were built on Whitworth MK X actions in 1987, just before Remington came out with the .416 RemMag, boo-hoo.

Watts also did a 2.5" .450 Watts Short before the .458 Winchester Magnum was released to the public in 1956, after James Watts "released " it to Winchester in the year 1954 or before.

Fred N. Barnes was offering his proprietary 450 B-J Express (Barnes-Johnson) in a lineup of "short magnum" cartridges from 7mm to .458 caliber, in the early 1950s.
He claimed his 450 B-J Express was being chambered and rifles sold "several years before Winchester added the .458 to their line."
The B-J express line all had 2.5" belted H&H Magnum ("short magnum") cases with the case body length to shoulder being 2.125", shoulder diameter 0.500", shoulder hemi-angle 35*.
He said in his March 15, 1958 pamphlet:
"450 B-J Express
The most powerful of the B-J Line. Shoots a 500 gr. bullet at 2200 f.s. Works perfectly in any standard length action. Rifles chambered for this cartridge will also shoot the new .458 Winchester factory cartridge.
While this is a so-called improved version of the .458 Winchester we chambered rifles for the .450 B-J several years before Winchester added the .458 to their line."

Seems Fred N. Barnes might have given Winchester ideas about the .338 WinMag and .264 WinMag too.

So when you say "improved .458" it stirs up thoughts of something other than the .450 Ackley Magnum.
Most likely it is a .450 Ackley Magnum if built on a 1917 Enfield and has a +3.6" magazine box internal length.
Mind your P's and Q's and get a chamber cast if any questions.
Firing a factory .458 Lott cartridge in your rifle to get a short-necked version of the .450 Ackley Magnum would be a sort of chamber cast, in brass.
An actual chamber cast would tell you more about the throat.
Lacking that, check the throat length with dummy cartridges using .458 Lott brass before shooting it.

Thanks Rifle,
Here are a few measurements if you don’t mind looking?
Image1730414691.062533.jpg
The magazine block is 3 3/4 inches
Image1730414737.804422.jpg
I’m calling that the receiver is 3 1/2 inches
Image1730414912.916532.jpg
Image1730414926.124693.jpg
The 06 and a 300 win mag sitting on the bolt both show room left over for the 450 or 458.
 

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Hold up !
I just saw your images of the bolt face that looks too big for an H&H belted case.
Looks like a .416 Rigby or .460 Weatherby size bolt face.
Do not fire .458 Lott ammo in that rifle until you get a chamber cast.
Slug your barrel also to check the rifling groove diameter, easy if the number of grooves is even (2, 4, 6, 8, etc.)
but hard to interpret accurately if the number of grooves is odd (3,5,7, 9, etc.).
 
Hold up !
I just saw your images of the bolt face that looks too big for an H&H belted case.
Looks like a .416 Rigby or .460 Weatherby size bolt face.
Do not fire .458 Lott ammo in that rifle until you get a chamber cast.
Slug your barrel also to check the rifling groove diameter, easy if the number of grooves is even (2, 4, 6, 8, etc.)
but hard to interpret accurately if the number of grooves is odd (3,5,7, 9, etc.).
Stay tuned my wife has some Cerrosafe ordered and I will pour a cast of the chamber this weekend. This is exciting because I didn’t know what Cerrosafe was until 30 minutes ago!
It’s great a little bit of knowledge from others goes a long way…
 
Michael458,
No apologies for wandering off topic.
It is all on topic and welcome words if coming from you.
Agree on twist, 1:12" for .416 Dakota I had built on an M70 RUM action.
My .500 wildcats have used 1:12" X2 rifles.
My .510 wildcats have used 1:10" X 3 rifles, 1:12" X 2 rifles, 1:20" X2 rifles, and a 1:9" X1 rifle.
The slow twists of 1:20" were on my ".500 Jeffery Match" (that is the CIP spec for .500 Jeffery) and on
my ".50-70 Little Bighorn."
Both meant primarily for heavy cast bullet fun, with the .500 Jeffery Match being fully equivalent to a .50-140 Sharps for BPCR "match" work, heh-heh-heh.

1:12" was also used on .35 Whelen, .35 Brown Whelen and (Lord help me !) my 5-different .395 Wildcats in 6 different rifles.

1:12" even works great on a .300 WinMag with 185-gr Berger VLD Match Grade Hunting bullets in a custom rifle of a friend that gets them up to 3160 fps MV from a 24" barrel !

For .458 WinMag 1:14" is great.
So is 1:10" which I have from Pac-Nor on a .458 WM+ and a .458 B&M+.
Any velocity or pressure changes with twist in going from 1:14" to 1:10" are nil.
The .458 B&M is a fantastic cartridge, my favorite of your B&M line.

I think a faster twist also helps with the transition from air to animal tissue or other denser media,
to keep the FN solid on course even if it does not impact the surface of the target perfectly normal/perpendicular.

You can even get by with cast bullets in 1:14" twist at usual velocities in a .458 WinMag.
1:10" is a bit too fast unless you are using really heavy ones subsonic, like 600 to 750-grainers.
 
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Back in the old days before I knew of the McCourry Institute of Ballistics (MIB) headed by Doctor McCourry (Doc M) in South Carolina it was rough.
I was trying to interrogate bullets myself in what I called the Iron WaterBoard Buffalo.
I quit the torture soon as I had access to MIB data.
I will claim to have suggested the "witness cards" to Doc M by using the cardstock found in storage bags and boxes of my comic book collection.
He immediately improved on this with the idea of laminating some larger cardstock to fit his bullet trap cross-section.

a002.jpg


a003.jpg


a004.jpg

Frozen waterdrops one winter night after testing a custom .500 Jeffery bullet from a forum member with handle "Jeffery_in_Denmark." He mailed the bullets from Denmark.
a005.jpg


a006.jpg



a007.jpg



a008.jpg


a009.jpg


Penetration scores:
GSC 340-gr/.395 Copper FN: 7.0-
S&H 330-gr/.395 Brass FN: 8.0+
Out of a possible 10.0

I never got around to trying a .50 BMG or a .416 Barrett with proper brass FN solids at maximum velocities from 32" barrels.

Jeffery_in_Denmark's 540-grain/.510-caliber Copper Monometal Cup Point scored only 49" or 5.0-. Impact velocity was about 2400 fps from my .500 A-Square with 1:10" twist.
Impressive for an "expanding solid."
See 5 missing buckets in nighttime photo of IWBB above.
 
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Just to continue the hijack, here is how Mike Brady, originator of North Fork Bullets, tested bullets,
with blocks of bookbinder glue that could be melted and moulded for re-use after he blew them up inside a long, steel drum with doors on the side:

a010.jpg


a011.jpg
a012 Northfork2.jpg


Nowadays, to me, only .458-caliber bullet tests are interesting, just like an accurate .458 WinMag rifle.
There, back on topic.
 
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Seeing as both the 500 Jeffery and 505 Gibbs cartridges both have dedicated threads, I thought I’d give Africas #1 underdog the same love.

We all know the history of the 458 WinMag and the teething issues it experienced in the early years. We also know those issues have been resolved with modern powders and bullets.

Modern factory ammo will produce 2,100-2,140 fps for 500 grain bullets out of a 24” barrel and reloading will easily let you surpass 2,150 fps.

Considering the vaunted 450NE produced these velocities (sometimes less in reality) with a 480gr bullet which proved more than adequate on everything up to and including elephant, the 458 WM is more of the same with a higher S.D of .341.

5,100+ft-lbs of energy out of the lowest recoiling of the 0.458 DG cartridges at sub 65 ft-lbs out of a 10 lbs rifle, why would you ever want or need more with the additional recoil penalty?

Due to the cartridges compact OAL it can be used in a standard length action, not requiring a bulkier or more expensive magnum length action.

The cartridge can be reloaded with an extremely versatile range of projectiles ranging between 250-550gr making it suitable for everything from white tail and hogs up to bull elephant.

All in a relatively light and affordable package with readily available and affordable ammo (by DG standards).

What’s not to love? It’s like hitting the easy button.
So, the 38 spl is better than a 357 mag?
Never have understood the love for the Win Mag but hate of the Lott. In these times of limited ammo and reloading supplies availability, the Lott opens up "a lot" of options.
 
So, the 38 spl is better than a 357 mag?
Never have understood the love for the Win Mag but hate of the Lott. In these times of limited ammo and reloading supplies availability, the Lott opens up "a lot" of options.
Seriously? A fondness for the Win does not mean a hatred of the Lott. They both have their place. There are advantages to both. A failure to recognize the advantages of the Win does not make the Lott better. The standard length action, easier to find and less expensive ammo (and yes you can shoot .458 Win in a Lott rifle, but if you do that you'll have to resight the gun), and the fact that Win will completely transect a buffalo or elephant skull making the extra recoil somewhat unnecessary.

If you want the extra power of the Lott that's great, but it does not make the Win irrelevant.
 
So, the 38 spl is better than a 357 mag?
Never have understood the love for the Win Mag but hate of the Lott. In these times of limited ammo and reloading supplies availability, the Lott opens up "a lot" of options.
What's the ammo situation like where you are? 458 WM is far more common here than 458 Lott and cheaper per round overall.
 
I already have model 70s in 375 H&H and 416 Rem, the next time Winchester makes a new run of 458s I think I need one to try out.

I don’t expect to be disappointed. Two of my rifles are from New Haven, but the 375 Alaskan is from Portugal.

Frankly both New Haven guns needed a little work to feed perfectly, but the new production M70 has been perfect right out of the box.

I have used the 375 with reduced loads( 235 grain TSX @ 2600 fps) on local hogs with perfect results. Also used full power loads in 375 and 416.

It would be fun to do the same thing in 458 with 45/70 bullets at 2500-2600 fps.

I have plenty of test media for the bullets, having caught around 400 wild hogs in a Boar Buster Trap over the last 4 years.

I like to shoot the big boars with big bores. ( pun intended) Shooting them broadside tells you something about incapacitating effect.

Length wise gives you insight into penetration.

Making the best use of the feral hog explosion
and all…
 
So, the 38 spl is better than a 357 mag?
Never have understood the love for the Win Mag but hate of the Lott. In these times of limited ammo and reloading supplies availability, the Lott opens up "a lot" of options.
Good work Northern Shooter.
Got them bitter clingers to their .458 Lotts flushing like a covey of quail.
Makes my heart go pity-patter.
Actually my .357 RM S&W 360PD has a 1-7/8" barrel, weighs 11.7 oz empty,
and with .357 loads of medium hotness they turn my "pocket pistol" into the equivalent of my 6"-barreled Python shooting .38 Special. Very nice.
 
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I picked up a CZ 458 Lott AHR #2 a while back. Really just cause I never shot one and all the horrible recoil talk. Found a M70 458 Win mag early this year. Figured I'll see what all the bashing is about with a legit comparison. This thread is extremely enjoyable and informative. Thank you gentleman.
 
Good work Northern Shooter.
Got them bitter clingers to their .458 Lotts flushing like a covey of quail.
Makes my heart go pity-patter.
Actually my .357 RM S&W 360PD has a 1-7/8" barrel, weighs 11.7 oz empty,
and with .357 loads of medium hotness they turn my "pocket pistol" into the equivalent of my 6"-barreled Python shooting .38 Special. Very nice.
Says the person that has made a career of spreading half truths to inflate his own ego.
 
I posted this in another thread thinking it was this one? I was a little foggy eyed I think lol But thought I’d post again in the correct thread for posterity…

This is my 2002 Winchester Custom Shop 458WinMag with a 22” bbl that shoots Hornady DGS to an honest 2170ftps and DGX to 2150ftps! This was verified through both LabRadar and Garmin Doppler double verified! My best friend and @CoElkHunter witnessed…
That easily matches the 450NE or 470NE so what more do you want?!?!
Seriously! All the 458WinMag sceptics WHAT MORE DO YOU WANT!!! :LOL:
Now I have no hate for the 458 Lott, but as a client I don’t see any imaginable reason for it? None!
The Lott these days is a specialized cartridge, like the Cap and the 500’s, for DG PH’s! And even then as the boys at Dalton and York who hunt a ton of DG will tell you the 458WinMag is plenty as that is what they use…
I have an upcoming DG for both Ele and Buff on the Save. My PH asked me what I’d be bringing and I told him that I have a 375 H&H, a 416 Rem, and a 458WinMg and he said without hesitation “Bring the 458!”. That’s all I need to know on the subject as he does this for a living!
IMG_0459.jpeg

IMG_0410.jpeg


That is the Custom Shop 458 on the bottom that I gave to my nephew and that is a 50 yard three shot group open sight out my 458 with DGS! Again what more do you want?
 

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Grz63 wrote on roklok's profile.
Hi Roklok
I read your post on Caprivi. Congratulations.
I plan to hunt there for buff in 2026 oct.
How was the land, very dry ? But à lot of buffs ?
Thank you / merci
Philippe
Fire Dog wrote on AfricaHunting.com's profile.
Chopped up the whole thing as I kept hitting the 240 character limit...
Found out the trigger word in the end... It was muzzle or velocity. dropped them and it posted.:)
Fire Dog wrote on AfricaHunting.com's profile.
2,822fps, ES 8.2
This compares favorably to 7 Rem Mag. with less powder & recoil.
Fire Dog wrote on AfricaHunting.com's profile.
*PLEASE NOTE THAT THIS IS FOR MY RIFLE, ALWAYS APPROACH A NEW LOAD CAUTIOUSLY!!*
Rifle is a Pierce long action, 32" 1:8.5 twist Swan{Au} barrel
{You will want a 1:8.5 to run the heavies but can get away with a 1:9}
Peterson .280AI brass, CCI 200 primers, 56.5gr of 4831SC, 184gr Berger Hybrid.
Fire Dog wrote on AfricaHunting.com's profile.
I know that this thread is more than a year old but as a new member I thought I would pass along my .280AI loading.
I am shooting F Open long range rather than hunting but here is what is working for me and I have managed a 198.14 at 800 meters.
That is for 20 shots. The 14 are X's which is a 5" circle.
 
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