458 Win Mag vs 458 Lott....The facts

At Equal cartridge overall lengths, you have the same case capacities. The 458 Winchester advantage becomes the longer SAAMI throat when in conjunction with a 3.6" magazine. Pretty easy to get the 3.6" advantage with a Winchester M70 Classic with minor modifications.

A re-chambered 458 Lott, from a SAAMI 458 Winchester, with the CZ's longer magazine allows for more case capacity in the longer 458 Lott brass, at a longer cartridge overall length than the 458 Winchester can accommodate. Most evident the shorter the actual bullet's length.

Of course, none of this matters unless you hand load, or have someone load for your specific rifles.

Personally, the I like the 3.4" magazine loads in the 458 Winchester. I don't think they will be the cause of anyone being mauled or stomped into a bloody mush.
I have a CZ 458 Winchester / 458 Lott and a MRC 3.6" magazine one.
 
The bottom line is while the Winny is enough, anything the Winny can do the Lott can do better. .3" longer case is why......

:cool:
Only if you run a SAAMI .458 WinMag reamer into the SAAMI .458 Lott chamber can it reach the performance level of the .458 WinMag allowed to be handloaded to .458 WM+ class.
Same pressures for both. No handicapping of the .458 WinMag with a lower MAP than the .458 Lott.

And, how does the .458 Lott do when you fit it into a .30-06-length action ?
Oh, I forgot, it does better with No. 9 shot for rats and snakes.
 
Wow, this is truly getting wearisome. On to more interesting discussions about actually hunting something.
 
ldmay375, you need a correction on your thinking here:

"A re-chambered 458 Lott, from a SAAMI 458 Winchester, with the CZ's longer magazine allows for more case capacity in the longer 458 Lott brass, at a longer cartridge overall length than the 458 Winchester can accommodate. Most evident the shorter the actual bullet's length."

No.
The limiting factor here is the throat itself.
With 2.5" brass or 2.8" brass in a 3.8" magazine length,
with a 500-gr TSX bullet the maximum COL before jamming bullet into the lands is like this:

SAAMI .458 Winchester Magnum: 3.780"
SAAMI .458 Lott: 3.622"

That is if the two rifles being compared are made to SAAMI minimum chamber specs and use the same bullet, identical in ogive to the lot I have.
Individual rifles may vary from this due to the plus tolerance allowed which still meets the minimum chamber specs, to fit the maximum ammo specs.

Distance from breech face to first contact of a .458-caliber rifling diameter at start of lands in a .458"-grooved, minimum SAAMI spec barrel for .458-caliber rifles:

SAAMI .458 Winchester Magnum: 3.1725"
SAAMI .458 Lott: 3.0143"

Undeniable truth:
The SAAMI .458 Winchester Magnum has a longer chamber than the SAAMI .458 Lott.
 
To reiterate, skip to bolded words of Phil Shoemaker below if Lottite reading comprehension and retention was adequate from first time:

Hype. That is how the .458 Lott made its reputation.
Jack Lott gut-shot a cape buffalo with a 510-gr RNSP from his .458 WinMag in 1959, Mozambique.
His next shot was the 500-gr FMJ RN "solid" that deformed and failed due to the high velocity of that factory ammo, and the poor construction of the factory bullet of the day.
Any higher MV would have made it worse.
Jack got tossed and some how emerged from the bushes with his worst injury being a corneal abrasion that got a complication and it took a few weeks for him to be able to see well enough to return to hunting in Mozambique with PH Wally Johnson (Walter Johnson, Sr.)
BTW, after Wally Johnson distracted the cape buffalo that Jack angered, by emptying his .375 H&H into that cape buffalo, he picked up Jack's .458 WinMag off the ground and killed the buffalo.

Fast forward from 1959 to 1971 during which time Jack continued to safari with a .458 WinMag, as did his buddy/editor Tom Siatos. Then they got the wildcatting wild hair. Tom did the 460 G&A, and inspired Jack to do the .458 Lott in 1971.

Eventually the story of "the .458 Winchester Magnum failure" morphed into no fault of Jack's gut-shooting. And the legendary .458 Lott hype began.
Never mind that Jack used a .450 Watts Magnum reamer with no throat to run into the chamber of a SAAMI .458 WinMag, preserving the terminal leade of the .458 WinMag to create the .458 Lott Wildcat by trimming the brass to 2.800". When you fire-form .375 H&H brass into .458 Lott diameter,
it shortens so that you have to trim it down to uniform and square the case mouths.
The first .458 Lott wildcat was a ".458 Lott Special" that could perform just like a SAAMI .458 WinMag firing .458 WM+ handloads, unlike the SAAMI .458 Lott with Art Alphin's fingerprints all over it.

Phil Shoemaker added:

"Jack’s self serving 180 degree 'report' was then taken up as a battle cry by a few high profile gun scribes and journalists with absolutely no experience with the 458 Win , but thought it a good way to further their writing careers."
 
ldmay375, you need a correction on your thinking here:

"A re-chambered 458 Lott, from a SAAMI 458 Winchester, with the CZ's longer magazine allows for more case capacity in the longer 458 Lott brass, at a longer cartridge overall length than the 458 Winchester can accommodate. Most evident the shorter the actual bullet's length."

No.
The limiting factor here is the throat itself.
With 2.5" brass or 2.8" brass in a 3.8" magazine length,
with a 500-gr TSX bullet the maximum COL before jamming bullet into the lands is like this:

SAAMI .458 Winchester Magnum: 3.780"
SAAMI .458 Lott: 3.622"

That is if the two rifles being compared are made to SAAMI minimum chamber specs and use the same bullet, identical in ogive to the lot I have.
Individual rifles may vary from this due to the plus tolerance allowed which still meets the minimum chamber specs, to fit the maximum ammo specs.

Distance from breech face to first contact of a .458-caliber rifling diameter at start of lands in a .458"-grooved, minimum SAAMI spec barrel for .458-caliber rifles:

SAAMI .458 Winchester Magnum: 3.1725"
SAAMI .458 Lott: 3.0143"

Undeniable truth:
The SAAMI .458 Winchester Magnum has a longer chamber than the SAAMI .458 Lott.
I have no doubt what you are saying is true.
The ogive contact being the limiting point.

I don't have any .458 500 grain TSX. But, I do have the 450's. This is specific to my particular CZ 458 Winchester / Lott, with this 450 TSX and once fired 458 Lott brass.
A very quick redneck check of throat. I think it can be loaded slightly longer before rifling contact. But I am already seated at about middle ways of the bullet base, on this 450 TSX. Which is seated longer than this rifle's magazine. It is roughly 4.11" COL. I did not spend the time truing up on the rifle for precisely accurate photo.



2509BF63-664B-41A0-92B5-3B3CDDB0D642.jpeg


3F184AB1-F4D1-4174-891C-B2E6715C4A9B.jpeg
 
Only if you run a SAAMI .458 WinMag reamer into the SAAMI .458 Lott chamber can it reach the performance level of the .458 WinMag allowed to be handloaded to .458 WM+ class.
Same pressures for both. No handicapping of the .458 WinMag with a lower MAP than the .458 Lott.

And, how does the .458 Lott do when you fit it into a .30-06-length action ?
Oh, I forgot, it does better with No. 9 shot for rats and snakes.

Incorrect. As I mentioned before, there are several ways to achieve the true potential of a 458 Lott. They are all exceedingly easy to do.

The only way to make a 458 Win exceed a Lott is to artificially restrict the Lott to a less than optimum COAL while maximizing the the 458 Win COAL.

Anyone who would buy into doing that shouldn't be hunting DG and therefore has no need for either the 458 Win or 458 Lott.
 
ldmay375:
You must have one of those early CZ .458 Lott rifles chambered with the original CIP homologation reamers. Max COL with that bullet would be about 4.080" in such a rifle using my ogive, similar to yours.
Maybe you have some slop that exceeds the original CIP minimum, or maybe not, close enough.
A little over the minimum would still be "in-spec" according to how CIP did it before SAAMI did it.
You do not have a SAAMI .458 Lott if you can chamber that.
Current CIP is same as SAAMI for the .458 Lott.
 
Last edited:
As this cartridge stands, 4.1120" COL. And possibly a tiny more is available. I seated where there is no rifling contact.

Yes, I think this is an early rifle. If one desired single loads, it will eject loaded at this length. I don't. I have not messed with determining the groove seating depth vs magazine length. Because, I load to the MRC's magazine length. But, I am not going to run out of throat with this rifle and a 450 TSX. The magazine is definitely the limiting factor.

All fun and games, and a learning process. But, I am still a 3.4" 458 Winchester guy. Pure simplicity, function, and performance when loaded to near magazine length.
 
Wow, this is truly getting wearisome. On to more interesting discussions about actually hunting something.

Incorrect. As I mentioned before, there are several ways to achieve the true potential of a 458 Lott. They are all exceedingly easy to do.

The only way to make a 458 Win exceed a Lott is to artificially restrict the Lott to a less than optimum COAL while maximizing the the 458 Win COAL.

Anyone who would buy into doing that shouldn't be hunting DG and therefore has no need for either the 458 Win or 458 Lott.




When you stretch a brass case by 0.3" and then shoehorn it into a magazine action that is only 0.2" longer, you get problems with the pre-existing .458 heavy bullets that fit so well at 3.34" COL on a 2.5" case length in a 3.4" magazine.
If you then put that 0.3" longer case into a magazine action that is another 0.2" longer than that (from 3.4" to 3.6" to 3.8"magazine length, spelled out so intj doesn't get confused)
you have more freedom to load longer than 3.6" COL with the SAAMI .458 Lott chamber,
but the throat is so short that you cannot do much more.
See notes above to ldmay375.
 
Last edited by a moderator:
As this cartridge stands, 4.1120" COL. And possibly a tiny more is available. I seated where there is no rifling contact.

Yes, I think this is an early rifle. If one desired single loads, it will eject loaded at this length. I don't. I have not messed with determining the groove seating depth vs magazine length. Because, I load to the MRC's magazine length. But, I am not going to run out of throat with this rifle and a 450 TSX. The magazine is definitely the limiting factor.

All fun and games, and a learning process. But, I am still a 3.4" 458 Winchester guy. Pure simplicity, function, and performance when loaded to near magazine length.
Makes perfect sense.
I still like the 3.4" magazine best of all too.
But 3.6" and 3.8" magazines and even single shots do have their uses.
 
Yes truly wearisome that intj is so incorrect about incorrect.
Plumb tedious that so many Lottites just want to take their toy and go home, do not play well with others.

When you stretch a brass case by 0.3" and then shoehorn it into a magazine action that is only 0.2" longer, you get problems with the pre-existing .458 heavy bullets that fit so well at 3.34" COL on a 2.5" case length in a 3.4" magazine.
If you then put that 0.3" longer case into a magazine action that is another 0.2" longer than that (from 3.4" to 3.6" to 3.8"magazine length, spelled out so intj doesn't get confused)
you have more freedom to load longer than 3.6" COL with the SAAMI .458 Lott chamber,
but the throat is so short that you cannot do much more.
See notes above to ldmay375.
I think he gets it now.
I think he has a higher IQ than intj.

LOL!! I realize that people believe what they want to believe, but still........

No one who knows a modicum about bolt action rifles will shoehorn a cartridge into too short of a magazine. A huge focus of the custom rifle building industry is to maximize the potential of each cartridge. This has been going on for years.

Many OEMs, probably in an effort to minimize costs, married themselves to a 3.4" magazine length. At first, it made sense, but it quickly reached the point of absurdity. The biggest example I can think of is Winchester putting a spacer in their 3.6" magazine boxes for many cartridges that worked better in longer magazine boxes. These cartridges worked better in longer magazine boxes well before the current trend of using heavy for caliber bullets. I have been removing magazine spacers, and shortening bolt stops and ejectors, on my M-70s for 20+ years. Later I started milling receivers to use Kevin Wyatt's magazine boxes.

Some OEMs broke the 3.4" restriction and Settled on 3.7" (Remington), but they became stuck there. Some OEMs like Tikka have regressed, offering a 300 Win Mag in their 3.4" magazine box. Some OEMs have done better, like CZ with their 3.850 length, but most of the solutions are in the aftermarket and custom gun world.

My company has worked very hard to address this well known issue. We have a DBM that will allow a 3.95" OAL. This works well on several premium aftermarket long actions and even a modified Remmy. We have a medium length DBM that allows 3.4" in certain medium actions, and we have a 3.15" magazine that fits certain short actions. Given the popularity of Tikka, we also make a 3.5" DBM and Mag for Tikkas.

All this make a huge different in performance. A long throated 300 WSM with a +P throat can shoot Berger 215s to 2900 fps+ from 22-24" barrels. A SAAMI 300 WSM can't even come close, IF you can even seat that bullet so the ogive is forward of the case mouth.

The 300 RUM and 338 Edge really need a 3.95ish COAL to be happy with heavy for caliber bullets, and the 338 Lapua IMP likes it as well. In the past, we just had to single feed these or accept too short of COALs.

In one of my M-70s, I installed a Wyatt's box (3.825"), long throated it, did a +P throat, and chambered it in 33-28 Nosler. It achieved 2925 fps with a Berger 300 OTM in a 26" barrel.

When it comes to straightish walled 458 cal cases, COAL is a huge factor in case capacity. The main reason to stretch maximize these COALs isn't to achieve higher velocities, it's to achieve the same velocities at a little lower pressure.

That is the main reason, along with building a Lott on my CZ, I'll be putting a Wyatt's box in my M-70 416 Rem. At 2430 FPS the 400 grain SAF hammered my buffalo, but in a 3.825" magazine box it will get that velocity at a little lower pressure. It will also allow me to better run 400 grain monos.

Long throats and long magazines are so common nowadays that it is beyond ludicrous to make the argument you are making about the 458 Win and 458 Lott. Anyone who can afford to go on a DG hunt can easily afford the few dollars it takes to optimize the magazine and throat on their 458 Lott or whatever.
 
Wow, this is truly getting wearisome. On to more interesting discussions about actually hunting something.

I have to agree, but most of us are probably "gun nerds" to one degree or another.

I think the old .458 Winchester is just fine and the .458 Lott would have never come to be if, there were really good bullets available 50 years ago, like there are today.
 
These are the COL's for my 458 Winchesters with the 450 grain TSX. These 458 Winchesters also have varying lengths.
The Interarms 458 Winchester at 3.838" is slightly longer than my MRC Lott at 3.820".
My rifles and bullets may vary from yours.
The 458 Lott picture is attached for comparison.

CA10309F-1D74-49CA-9704-91C69DB12602.jpeg


C4FD9611-BFFD-4CE0-A789-C51B5B66A875.jpeg
 
ldmay375,
No typo on mine. Maybe I had a precision job by a Master Gunsmith and got a minimum-throated .458 WinMag SAAMI-chambered wunderrifle ?

With minimum SAAMI chambers
the distance from breech face to .458"-diameter contact
at the start of the lands in a .458"-grooved/.450"-bored barrel:

.458 WM = 3.1725"
.458 Lott = 3.0140"

Add the ogive length of the particular bullet to that
to see what the maximum COL will be to just touch the rifling lands.

I do know that the TSX bullets vary some.
One lot of my 500-grainers was 1.670" long and another was 1.650" long (BOL).
Ogives lengths could be variable too.

Judging by your .458 Lott rifles, both of them have been long throated.
They are not SAAMI .458 Lott.

That CZ of yours looks like it was done with a reamer from the original CIP homologation.
I have that CIP drawing dated 08-24-2000 and revised 05-15-2002 and it still had the LONG-LEADE-ONLY-THROAT,
same throat as on the SAAMI .458 WinMag, tacked onto the end of the 2.800"-brass accepting chamber.
Then on 05-16-2006 CIP revised their homologation again to match the SAAMI .458 Lott throat:
Short parallel-sided free-bore of 0.459" diameter and only 0.178" length leading into an abrupt leade angle of 2 degrees (4-degree cone angle).

Is that MRC .458 Lott a custom job or a factory job ?
That 3.59" magazine box length is mighty short.
The 3.6" boxes are usually more like +3.6" like at least 3.62" inside length.
Anyway, it seems to be a ".458 Lott Special" with a little extra special in it,
but not as much as the CZ ".458 Lott Extra Special."

As for your longer-throated-than-mine .458 WinMags, I am amazed.
I knew the .458 Lott throats varied all over the place,
did not know that factory .458 WinMag rifles did too.
Finn Aagaard had some like that, and I figured his throats were lengthened by erosion of thousands of rounds fired with the old steel-jacketed FMJs.
His 425 Westley Richards re-barreled to .458 WinMag had a very short throat,
I figured it started life with no throat and he likewise shot some throat into it by wear and tear.
 
Yes indeed, one must know his rifle.

This paper-patch-BPCR method of Randolph S. Wright may be adapted for comparing throats (excellent book):

z005.JPG


z006.JPG


z007.JPG


My doodling on a tool:
0-1.JPG
 
Last edited:
I will try to reply to everything. If I miss something let me know.

All of these rifles were bought used. Though, all appeared as dang near new, literally.
So, I am assuming the throats were as factory reamed.
The MRC magazine is a nominal 3.6", perhaps a tiny longer. I actually load it to 3.5960" to allow me, real or imagined comfort level on COL and ogive variations.

The Winchester Model 70 Super Express throat surprised the heck out of me. I measured, re-measured and Re-measured ...
But, they came out consistent. This one may be a potential candidate for one of the spare 3.6" replacement magazines that I have around here. But, I will probably be putting it in a fiberglass stock, before the additional recoil. I would say throat erosion is not a factor on this one. It literally looked like new. I think I got 2 or 3 boxes of the Hornady super-whatever 500 grain with it, missing with 2 or 3 fired brass in one box.

The CZ had a trip to AHR prior to my purchase. But it also looked new. Now that one, I never bothered to measure. I shot some factory loads through it. I sort of did, but realized the 450's were dang near out of the brass, and the test COL cartridge from the MRC at 3.8205" worked through the magazine without issue. And called it good enough since all my Lott loads were for the MRC. Heck, I just "assumed" it was a SAAMI Winchester throat. Which would have been no issue with the MRC loaded lengths since I was not looking to maximize it.

Edit: I had a picture of the AHR work order on the CZ. No chamber work was listed.
 
Last edited:

Forum statistics

Threads
58,288
Messages
1,253,830
Members
103,762
Latest member
DustinMerr
 

 

 

Latest profile posts

Everyone always thinks about the worst thing that can happen, maybe ask yourself what's the best outcome that could happen?
Big areas means BIG ELAND BULLS!!
d5fd1546-d747-4625-b730-e8f35d4a4fed.jpeg
autofire wrote on LIMPOPO NORTH SAFARIS's profile.
Do you have any cull hunts available? 7 days, daily rate plus per animal price?
 
Top