Home Forums Hunting & Shooting Express Rifles and Big Bores Only ".458 Magnum Mystery Solved!" by Jim Carmichel. Has anyone read it?

According to this article in OUTDOOR LIFE, March, 2009, a former Winchester engineer, Walter Engel, who was involved in the initial development of the 485 Win Mag, revealed in a published letter that the problems of erratic pressure and consequent velocity were due to powder being shaken out of the case in the production process. The amount of powder shaken out was not necessarily consistent so, in a box of 20, for example, there might have been great differences in pressure and velocity loss. This apparently was going on for a while without detection until, at some point, the production operation was altered.

In other words, it was not a situation of not being able to get enough powder into the case, but keeping it there before the bullet was seated.

It's a good read, and I encourage anyone interested in the facts (versus speculation and rumor)to read it.

We've heard lots of stories about the 458 WM case not holding enough powder. That has never been my experience, nor the experience of PH's and others who've seriously worked with the 458 WM in discovering it's full potential.

While I expect that some naysayers will continue to repeat worn out untruths, yet for the serious investigator it should put to rest once and for all such myths. What say you?

.

All of that is immaterial as anyone who has ever dreamed of owning a 458 Lott will tell you that while 400gr bullets from a 450/400 or 404 @ 2000fps are extremely deadly - a 500 gr bullet from a 458 Win @ 2000fps will bounce off anything larger than a coyote.

Doesn't surprise me any. It's as easy as falling off a log to load a .458 500 grain bullet to 2200 fps without excess pressure.

The powders available when the 458 Win Mag came out made it very difficult to achieve published velocities without excessive pressure. That is a documented fact. Today with the advent of new powders the 458 can reach the velocities it once claimed. Let's be candid, the main reason the 458 became the mainstay for DG hunting was the demise of the Anglo "Twin Tubes" when Kynoch stopped making ammo. In my view it was a poorly designed concept and a classic example of the "tail wagging the dog" as in Winchester wanted it in a standard length action. Then when the Lott became standard commercially loaded caliber, the 458 has lost a lot of ground. The Lott is what the 458 should have been all along. jorge

The only 458 that I have was a Interarms Whitworth and would do 2110 FPS with 500 grainers ahead off 74 grains of IMR-4895 and Federal 210 Primers. Not an amemic load IMHO

That's a pretty good load jwp. Was the powder compressed? jorge

Yes it was

There's part of the problem. Compressed loads like that from what I've read on the 458 tended to "cake" the powder. particularly if the ammo was old and gave erratic performance with factory loads. I had a Browning Safari in 458 with a 22" barrel that only gave me about 1910-50 fps with 510gr Winchester factory loads. jorge

I've heard quite a few times the powders available when the 458WM was introduced wouldn't provide 2100fps without extreme compression. A quick Google shows the 458WM born in 1956. Military 4895 was used during WWII and sold by Bruce Hodgden beginning in 1947 (another source says 1950). Was the early 4895 that much different than modern 4895 or did Winchester just use the wrong powder? I seem to remember the clumping of powder problems attributed to ball powder in the 458.

It is easy to get 2200 FPS out of a .458 Win with a long tube but you are also in some pretty grim pressure ranges and may end up with stuck cases or whatever in the hot climes..I have seen this happen..

I see little reason to load the 500 gr. 458 Win past 2000 FPS as it kills very well indeed at those velocities and pressures are tolerable..The 458 Win. problems, in the past, came about with factory ammo that competed with the 45-70, some as little as 1800 FPS to 1900 FPS and that is in the sho nuff iffy zone on big nasty creatures IMO...

I believe the .458s controvercy is well deserved as it has a too small case, end of story, it just does...A better solution to the 458 Win is to stick a reamer in it and make it a 458 Lott, a easy, inexpensive operation..Then as opposed to loading the hell out of the Lott, gear it down to a reasonable 2150 FPS, have mild recoil and very low chamber pressure, and a real knock'em in the dirt result on anything...

I see that as a perfect solution to all this gobbly goop of trying to protect the infamous 458 Win.s reputation...:)

As I said in the original post... there will still be those who hang on to their myths! The question was: Has anyone read Carmichel's article in Outdoor Life, in which he gives his own experience with the 458 WM in Africa, which contradicts everything Atkinson has said a million times?

www.bigbores.ca

No myth, CZ. I clocked my 458 Win Mag with the aforementioned Winchester factory loads and there are literally hundreds of documented incidents of 458WM squib loads, caked powder, etc IN THE PAST. But with today's powders the 458 can live up to it's potential. jorge

jorgeI;

No need to have a compressed load... Study Hodgdon Manual No.27 on the .458 WM.

From a 24" tube: 75.5 grs of H335 under the 500-gr Hornady = 2163 fps at 50,300 CUP. That's NOT a compressed load!

74 grs Varget = 2152 fps at 48,100 CUP, a lightly compressed load.

74 grs H4895 = 2161 fps at 50,300 CUP, a lightly compressed load.

I'd have NO problem with those loads in Africa, using either Varget or H4895. H4895 is renowned for temperature stability.

Other powders, such as AA2230, AA2460 and RL-15 are all excellent in the .458 WM. RL-15 is outstanding for being temperature insensitive.

AA powder data: 72 grs AA2230/500gr Hor/2159 fps at 53,808 psi

74 grs AA2460/500gr Hor/2192 fps at 52,864 psi

That's from a 24" tube and pressure is in psi, NOT CUP! The 458 WM is considered today to easily handle 62,000 psi! Those are low pressures and not compressed loads being ball powders.

So Ray, IndyCA35 is correct. 2200 fps is absolutely possible today within sane pressures and "uncaked" powders.

Bob

www.bigbores.ca

Concur, but the old ball sphericals were awful. jorge

I don't understand what's wrong with compressed loads of stick powder. Back in the early 1960s I commonly used compressed loads of H4831 with very long bullets in a 30-06 for 1000 yard matches. No big deal, and it gets 90 degrees F at Camp Perry, Ohio. My loads were very accurate and I don't think there was "clumping."

Also, I don't think there was any difference between IMR 4895 in the 1960s and now. I have just finished up my last IMR 4895 from that decade, loading some ammo for Garand matches with it. I don't see why a 500 grain .458 could not have been loaded to 2100 in 1960.

My experience differs. Although I chronographed 500 grain bullets at 2200, I elected to use 450 grain bullets at 2250 in Zim because I thought the flat point North Forks would give superior penetration. Neither showed any signs of high pressure. There were no problems with case extraction. My barrel is 22 inches.

"I clocked my 458 Win Mag with the aforementioned Winchester factory loads and there are literally hundreds of documented incidents of 458WM squib loads, caked powder, etc."

Jorge, the point of Carmichael's article is that the squib loads were caused by powder sloshing out of the cases in their loading process.

I can't comment on the caked powder except to wonder if it ever really happened. How does one tell after firing the round? How come it has never been reported, to my knowledge, in any other cartridge loaded with compressed loads? I also read someplace that Winchester initially glued in the bullets, and the glue got down into the powder.

The point is that the .458 is a fine round for launching 500 grain bullets at 2150 fps at reasonable pressures. The case is not too small.

Indy,
Thanks for the info on the early 4895. I have read accounts where cartridges from the same box were pulled apart after squib rounds were fired finding the powder in a solid mass which had to be dug out of the cases. The opinion was that the clumping of ball powders required heavy compression over time (years) and was accelerated by high temperatures, causing the coating on the grains to bond together. Stick powders don't seem to suffer from the same problem due to either different types of coating or because it doesn't pack together as tightly.

From Pierre van der Walt-
"The problem with the .458 Winchester Magnum arose when field ballistics did not live up to paper claims. Long barrels are not liked on dangerous game rifles, so hunters chopped the barrels - sacrificing some velocity in the process. There is no denying that Olin, the company that manufactured Winchester ammunition in the early days, made a terrible hash of manufacturing .458 Winchester Magnum ammunition. Stronger terms actually come to mind to appropriately define the situation.

Daan van Heerden and I once pulled bullets from still sealed boxes of old Winchester .458 factory ammunition. The results were shocking. I could not believe that coming from the same box, some cartridges were loaded with ball propellant and others with extruded propellant! Measuring the ball loads and extruded loads separately we could not even determine what the intended load for each actually was supposed to have been! This variation was consistent throughout all the old boxes checked.

Another problem identified by A-Square in Zimbabwe was that the coating on the granules of compressed loads of ball propellant caused the propellant to congeal into lumps. Combustion subsequently was incomplete and muzzle velocities as low as about 1,650 fps were apparently recorded. Not even remotely close to published figures - in fact that compares with blackpowder loads. All these problems caused the substandard field performance that resulted in the loss of public faith in the cartridge. Penetration was often poor and failures regular. The .458 Winchester Magnum soon acquired a bad reputation.

Although not easily, all the .458�s problems can be solved when handloading for the cartridge. Once success is achieved and the cartridge is brought up to original ballistic specification, it is as good as any classic English .458″ cartridge on the receiving end."
http://www.safariactionshooting.com/?page_id=188

(If I can find the article talking about pulling down the squib loads I'll post the link.)

My current favorite .458 load is approximately the same, but using the 450 grain TSX @ 2,270 fps (CZ 550 with 25" tube). It took me some time to warm up to the x-bullets, but I'm coming around ever so slowly. I've really not done much experimenting with any of the 500 grain bullets, but certainly had some loads -from years past- in the 2,200 fps range with no pressure issues (tropical climate or otherwise). I'm just now starting to mess around with this caliber again after not using it for probably 15 years.

Interesting thread.
But I am puzzled that this inherent powder inconsistency was NOT discovered immediately by the Winchester folks.
Certainly they did tests on these runs (lots?) of ammo as it was produced?
Interesting.
Hold into the wind
VarmintGuy

VarmintGuy,
It was discovered by Win. and most of the ammo companies very discreetly cut the powder charges and the velocities to about 1900 FPS or less in some cases..

I happen to disagree with some as to the virtues of the .458 and the 45-70, and that is one of the few rights we have left under the present administration!

I do agree and should state for those that seem to misread or misunderstand my posts on the .458 that I do believe the .458 is a viable caliber with proper handloads at 2000 to 2100 FPS with a 500 gr. bullet..I also believe that 2200 is pushing the string in hot climes or with rounds bouncing around for a year in the bakki etc. My only suggestion is to punch it out to a Lott for $50 and load it to the needed 2200 FPS if you must, that seems to make since to me! but in guns and horses one has to be careful when telling folks that the old smoke pole is faulted!

I also think that the 450 gr. 458 bullet sounds like a good load at 2200 FPS, but I have not used it on game..I did shoot a .458 for some years early on with good hand loads and had not problems killing anything with it at 2000 FPS..It is a real killer at that velocity, contrary to popular belief it seems. Likewise the .470 N.E.

The old Brit recipe was a .450 and 500 gr solid at 2,150 fps and 5,000 lb-ft energy, guaranteed to lay critters low if properly shot.

jim

And againnnn.....when will it ever end??? WHEN will people quit bringing up OLD crap that "maybe was" but is "now fixed".

People keep "disremembering" that barrel length, bullet seating depth, variance in rifle bores, loading techniques, chrono differences and variance in velocity readings, proprietary powder, IGNORANCE OF THE FACTS and a hundred other things can affect cartridge performance...any of which could have/HAS affected the 458 WM.

Todays 458 WM ammo, which I would use rather than something even 10 years old, has solved all the known glitches as far as I have read...of course if I were going after something that bites hard, I would build my own ammo out of recently made powder and primers and FIT to my gun...that way I the onus is on me.

Forums have now taken over the job of the barkeep or local pub so we can carp at anything and everything and forget about keeping things in perspective...want a donnybrook...just shoot off your mouth at the wrong time or place and you have one...except on the net you don't have to worry about getting busted up physically for mopery with intent to commit great stupidity...or what you deserve....

Just about ANY rifle chambered for the 458 WM has a magazine length sufficient handle a 3.5" cartridge...you can buy a cannelure making tool to put cannelures where YOU want it so YOU can come up with a non-compressed load...or as it is suggested rechamber to a Lott(much better solution) or one of the REAL hairy customs and quit your pissing in the wind...but no one wants to solve a problem...just whine about it using OLD information or just want to stir the pot...or just armchair.

Dammmm I build a 458 WM on a SMLE 2a action...max COAL of 3.1"...I have no trouble coming up with loads for a 400 gr bullet in the 2300 f/s range and just under 39KCUP...just look in the Hornady 2006 manual, I have to keep the pressure down because of the action, but I don't know of very many animals roaming the earth at this time that could take one of those rounds without wanting to find a nice soft place to lie down. I COULD come up with a 500 gr slug at 18-1900 fs if I wanted without any trouble and still at 3.00" COAL, but I have no use for that in the SMLE application, I have a 45-100 to handle that size and much heavier...

I mean really...a 22 in the eye into the brain will get you most animals if you have the ability...way too many people are living in the bottle, in their minds and on the net, now that this forum thing is taking over what little minds we have now....much worse than TV, VCR or DVD's I think.

Maybe new powders have resolved the early problems with the 458 win mag.

However I fail to see how the 458 Lott cannot do everything the win mag does just that little bit easier and probably with less felt recoil for the same velocity as the win mag.

A bit like a downloaded 378 wby versus a maxed out 375h&h.

Plus, my CZ 550 feeds the longer Lott case soo much better than the original win mag case!

No intention of starting a brawl, NFG, but I found Carmichel's article of interest, and perhaps helpful in understanding past issues with the 458 WM, and thought some others might have also, HAD THEY READ IT!

I was not naive, as some reaction was anticipated in regurgitating some past failures of 458 WM ammo.

As pointed out by Phil Shoemaker, and others, a whole bunch of DG cartridges have not lived up to pre-announcements either, falling short sometimes by quite a lot!

I could literally count on one hand the boxes of factory ammo I've shot in my rifles over the past thirty years and have three fingers left over! Modern ammo doesn't always live up to announcements either, and it has nothing to do with the case being too small!

A few years back, I wanted to take my then new 35 Whelen deer hunting before the dies for handloading were in. I bought an expensive box of 250 gr RN'S (all they had at the time) advertised as giving 2400 fps. I chronographed 10 of the 20... average speed = 2247 fps! I later discovered that my rifle was capable of 2600 fps from 250's with the right powder!

That's not shocking... but it's revealing. With the right combination of components today, most any rifle will outperform it's past history! If you want examples, I can give them... but that includes the 458 Win Mag also.

I've gotten 2712 fps from my 375 H&H shooting 300 gr N.P.'s. It was a book load using a modern powder from a 26" barrel!

I've received, from a companion rifle to that 375 H&H, 3215 fps from 180 gr N.P.'s in my 300 Win Mag... it had a 26" tube! From that same rifle 3000+ fps was possible from 200's.

Those are just a few examples, but they're not isolated! Nosler's latest manual shows 3 loads over 3100 fps from their 180's in a 24", 300 Win Mag test barrel. One load attains 3160 fps. From their 200's, one load records 2972 fps, another 2960 fps! Yet, there are still those who potificate that the 300 Win Mag will barely break 3000 fps from 180's! Remember, Nosler's numbers are from a 24" barrel. Mine were from a 26".

The point is a simple one: a 458 WM will EASILY attain 2150 fps from a 500gr Hornady WITHOUT max pressures or compression of powder, though I don't think light compression of powder is an issue at all!

And, BTW, my 458 is a CZ 550 that allows a COL of 3.75". IF I WANT TO USE IT! But, I'm not referring to my rifle in particular... just to 458's in general.

Bob

www.bigbores.ca

I don't think these issues have to be an arguement or a cat fight..IMO they are interesting discussions and nothing more...I mean what someone else shoots is of very little concern to me, as that is their decision to make...

I don't understand how some folks can become so emotional over a caliber of a rifle, as one is about as good as another and we all have some choices to make and many of us have used many of the calibers we discuss and by doing that have formed an opinnion and that is all it is, an opinnion, at least on my part.

The 458 Win is a viable DG rifle with proper bullets and loads and that is a 500 gr. bullet at a minimum velocity of 2000 FPS IMO...The use of lighter bullets is not the answer, again my opinnion as I want a 500 gr. bullet because it has great Sectional Density and that means penetration which is very important on most big animals.

I salute all of you and I find most opinnions interesting, and as always the .458 and 45-70 continue to flair emotions on the internet.

Ray,

Regarding light bullets, there is a whole lot of data that seems to support that a 450 grain North Fork or G.S. flat point solid will in fact out-penetrate a 500 grain solid bullet of the classic Kynoch shape. I chose the 450 grain bullets because (a) the penetration was at least as good, (b) felt recoil was less, and (c) I wanted to use Barnes 450 grain TSX bullets as my softpoints and I felt that 450 grain solids would shoot to the same point of aim. In fact, they shoot about an inch differently at 100 yards from my rifle. Velocity 10 feet off the muzzle is about 2250 in both cases, chronographed.

I don't think there is much of a pressure problem with the .458. The real problem is how much you can cram into the case. I use AA2230 because it is a little denser than H4895. Some loads I have seen published would seem almost impossible to me insofar as putting that much powder in the case.

I have heard that the Ramshot powders are dense. Anyone use any Ramshot powders with the .458?

Now as for clumping when bouncing around in the bakki for a year, I solved that. I load my hunting ammo a couple of weeks before the trip. The last trip I left all the unfired ammo there. PHs tend to keep all sorts of mismatched ammo around forever, because it is harder for them to get ammo. I don't have that problem and mine is "fresh."

Loading the .458 is just as easy as loading anything else, except that North Fork's solids have very narrow grooves, and you must pay attention that case lengths are all the same and seating depth is exact. If not, crimping them won't work well. North Fork says they may not feed in all rifles but mine fed perfectly in my rifle including multiple shots at dangerous game.

I'm not sure that simply reaming out a .458 to make a Lott is that simple. I have heard of some feeding problems when doing this. I see no reason to use a Lott so long as I can get 2150 with a 500 grain bullet or 2200+ with a 450 in the .458 Winchester.

Also I don't understand why you bring up the 45-70. Whatever is "magic" about a 500 grain bullet at 2150, you can't do it with a 45-70 and there is no need to load the .458 down to 2000. On the other hand, I have read somewhere that the old .450s 100 years ago had their ballistics taken in 28" barrels, and most of the actual .450 rifles you could buy had shorter barrels and shot nearer to 2000 fps.

Indy,
Point taken and I have no problem with your suggestions, just that I have a different approach to the .458 than you...You want to make it work and you have, and I said that it could be done in my posts and that I had used it succesfully..

My approach on the other hand is that I don't want to have to make any caliber work so why not chamber it out to .458 Lott and have the options that are available. If you like 2200 or whatever you have the option to do so, if you prefer a 500 gr. bullet at 2350 FPS thats an easy do in the Lott.

As to the Lott feeding that just isn't right if the gunsmith knows his business..Too many just ream it out and it feeds most of the time without tweeking, therein lies the problem. The longer round in not in timeing as the shorter 458 Win. You must do the rail work and fix the timing on it, but that is not a major problem at all...

Nothing is magic about 2150 FPS other than its supposed to be an ideal velocity for a 458 caliber bullet with a 500 gr. bullet. I used 2000 FPS as its easy to get too, never any pressure problems, its in the safety net for the 458 Win.., and it certainly is all one really needs to kill a buffalo, and extra 150 FPS is nice I suppose,but makes no difference to the buffalo...

I respect your opinnion on the .458 and certainly don't disagree with it, although some of your reasoning fails me, but that is your perogative for sure..

If I had another .458 Win. I would not be opposed to shooting a 500 gr. Woodleigh at 2000 or so FPS on anything including elephant,and I have done that, but in reality, I would probably punch it out to a Lott before I got to Africa this time! PLease allow me that?

OK, you have my permission to punch out your .458 to the Lott.

Best reason I can think of to prefer the original .458 is that I already had one plus ammo and brass before I got interested in African hunting!

I have a .458 WM that has served me quite well for the hunt I built it for (I did have some help from my father). Loaded with a 500gr Hornady and about 2150 fps. it did its job.

I am not really sure how much more cartridge could be crammed in a Mauser, but the .458 fits well enough. If I want something bigger its time to get a #1 and talk to my father about something like a .450 NE 3 1/4 or a .475 #2 Jeffery.

Indy,
Your got it! I agree...and I want to make it very clear that I never said the .458 was not a good cartridge as some proclaim I have said, all I ever said on the subject was that IMO there are better options, some don't think so such as yourself and I respect and bow to that decision, it is yours/theirs to make..

I do believe the 450 gr. Northforks and GS Customs make a real diffence in the .458 Win., when I posted that about 500 gr. bullets I was thinking in the past and have said that so many times over the years that its a habit! :), the world moves faster than my old brain does these days...

Mitdr774,
The 98 Mauser can be opened up to about any cartridge. In fact, I have seen a couple of Holland and Hollands, and one Rigby in .416 Rigby caliber, several 500 Jefferys, but thats close...

I have built a number of 404 on the std. 98 and I do feel that I'm pushing the string by doing that but they worked, after a lot of tweeking. To make a Mauser take a 458 Lott is a snap, plenty of room as the length of the Lott is 2.85 or 2.80 depending on who does it and the 3" does real well in the 98 and FNs also.

I think the best of the bunch is the new Ruger case opened up to 404, and the .416 is already available and you don't have to do much to make these shortys fit a M-98, you could almost do the rails with your fingernail! I would be curious as to what this fat little booger would do necked up to .458, sounds like a winner if you can get the velocity. It should work I think.

For me it was a matter of what I had available and could easily obtain. It did its job for me and I have no problem trusting it.

My father has tinkered around with building a .505 Gibbs (at least that is what I recall it being) on a M98 based action. However it seems to be an on and off project.

I dont have much experience with big bores and as a result I stuck with something more "common" and had easy access to equipment to build it and reload. As with most of my rifles, factory loads just dont shoot as well as I would like.

I've said it before but will state it again here - the more I experiment with other large bores the more impressed I am with the standard length 458 Win.
A 500 grain bullet @ an honest 2150fps from a standard length cartridge is hard to beat.

Phil,
I knew you would take the bait on this one, but like and old bear you were slow to take it...but I agree with your post..

Mittdr774,
The 505 Gibbs is just too big for a std Mauser and such a conversion would be dangerous IMO..I have seen a 98 in 500 Jefferys, but was not impressed with it either. A PH I know has a 416 Riby by Rigby on a 98 action, its pretty crowded in that box..

I just believe those big cases need to be on a Mod. 20 magnum action or one of its modern clones like the Victor.

Oh - Oh Ray, when we start agreeing does that mean we are getting old ?

I will just note that Harry Selby's famous .416 Rigby is on a standard 98 action--but the .416 Rigby is not a high-pressure cartridgem, at least when loaded to factory standards.

I find this a very interesting thread. I'd heard all the "powder clumping" and "compression" stories before. I never heard the loss of powder in loading though-nor the "glued bullets".
Several years ago the guy I bought my Lott from told me the 450 GS (he also used another 450 I can't remember) was a better choice even in the Lott than the 500gr. It gave better penetration he allowed. He had made several dozen trips to Africa so I took his opinion as worthy of consideration.
I have found in the 450 Dakota the 450 gr Northfork is superbly accurate @2270fps and it will be my load of choice when I get to finally to use it on something other than paper or milk jugs.
Great discussion

I was mistaken on the .505 Gibbs. He is working on a .500 Jeffery.

They will also tell you that a .45 or .50 bullet driven by a heavy load from a Winchester 1886 won't kill African game.

Or, at the very least, doing so is a "stunt"...........

Not confusing the argument about Weatherby Mark V actions versus controlled-feed actions but sticking to the issue of cartridges...

What's wrong with the 460 Weatherby case loaded to moderate pressures like the older British African rounds and pushing a 500 grain bullet easily to 2,200+ fps ?

Or for that matter a 600 grain bullet ?

.

Well to add to this drama..I talked to a gunsmith that has possession of the 'prototype' .458 Winchester 70.It's supposed to coming on the market for sale.His note of interest was the fact that the gun did not feed worth a crap and Winchester must have been playing around with mag boxes and followers to see what was needed for the new round.Maybe they were still trying to decide on the overall lenght?I found this interesting....

drducati,

If you search, you will find a lot of threads to the effect that 450 flat point solids will penetrate deeper than 500 grain round nosed solids due to a cavitation effect. Flat point solids are made by G.S. and North Fork. The latter are the most accurate big bullets I have tried in my .458. Haven't tried G.S. yet.

Nothing, but what's right with it? You can get 2200 easily with an ordinary .458 Winchester without high pressure, undue compression, compaction, glue, or the tooth fairy.

Although I have no experience with the .458, I did have Walt Engel as an engineering professor in the mid-1990's. I have to say that he was by far the best professor I had in six years of engineering school. He was by far one of smartest and most interesting people I have know. So if he thought there was a problem with the manufacturing process, I would bet my life on it.