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

The .458 WinMag with 500-grainer at 2170 fps and 3.406" COL is a low pressure load unless the Eland soft is a very weird bullet.
I would be surprised if that load had pressure over 60,000 psi.

In theory about the .458 Express 3" ?
.458 Express 3" throated like a SAAMI .458 WinMag and loaded in a Ruger No. 1 with the proper compressed load of slow-enough propellant to keep pressures below the 62,500 psi MAP of the SAAMI .458 Lott.
Is that the theory ?

BTW, CIP allows the same MAP to both the .458 WinMag and the .458 Lott.
What Norma specifies in their reloading manual:

458 Winchester Magnum: "4300 bar/62365 psi"

458 Lott: "4300 bar/62366 psi"

Rounded down for the WinMag and rounded up for the Lott.
1 psi advantage to the Lott.
Always trying to feather the nest of the .458 Lott !

CIP loads for the .458 WinMag are routinely .458 WM+ loads by SAAMI standards,
since SAAMI limits the .458 WinMag to 60,000 psi and allows the .458 Lott 62,500 psi.
They know they have to use higher pressures in the SAAMI .458 Lott to give it any advantage at all
versus the .458 WinMag.

Norma shows a 500-gr load for the .458 WinMag at 2175 fps from a 24" barrel of 1:14" twist.
with 73.5 grains of Norma 201.

Norma was so embarrassed by what they got for their .458 Lott, they decided to publish only reduced loads for the .458 Lott.

500-gr bullet in the .458 Lott at 2092 fps from a 24" barrel of 1:14" twist (not 1:10" per SAAMI/CIP)
with 75.9 grains of Norma 201.

More powder burned for less velocity. What's to like about that ?
Thanks Riflecrank - yes spot on, that is a Bertram case. We had another Big Bore shoot this past weekend, and the guy’s who’s case that is brought it to us and showed this exact mark. Brand new never been fired before. He was worried he would get case seperation, didn’t though. Next reload would be interesting! We all agreed this is not the case we would want near a rifle that would be hunting dangerous game.
 
Lol !!
A group photo, at morning coffee.

7C72DBFD-D329-42A2-B29B-D5C69D65B78A.jpeg
 
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Do not worry about African heat anymore than you do Texas or Arizona heat. It is a vestigial concern from the time when Brit’s took cordite loads to Africa.
In TX or AZ you are not hunting animals that might kill you if you gun locks up from to much pressure. And not all powders are temp insensitive.
 
In TX or AZ you are not hunting animals that might kill you if you gun locks up from to much pressure. And not all powders are temp insensitive.
I am not worried about it in Africa either with modern ammunition.
 
There still many popular powders that can change pressure significantly over broad ranges of temperature. In Canada, I am often testing loads in minus 20-30 temps... I always check them on site for any hunt where there is a considerable temperature change.
 
I think the elephant in the room, in regards to all of these pictures posted of bullets being seated way out, is the fact that I would never take this ammo on an actual DG hunt. A bullet seated so shallow in the case seems to be a disaster waiting to happen.
I have seated some bullets out a bit in my 458 Win Mag, but nothing as extreme as some of the pictures above. IMO, exceeding 458 Lott COL isn’t needed for hunting. But I suppose it’s ok for range work, where you’re just trying to get the most velocity possible.
 
Glad to see WAB is enjoying this.
I am too.

I find it quite amusing. Bottom line, where I hunt you’d be crazy to take a .458 WM. If something happens to your ammo you are
Going to have a heck of a time finding WM ammo. If you do find it, you’re shooting a 500 gr bullet at 2,100 if I’m generous. However, every camp has Lott ammo.

As stated previously, I am a very serious reloader. However, IMO, reloading for this class of cartridge is pointless. Buy a Lott, shoot factory ammo at 2,300 fps, and knock the crap out of buffalo and elephant. All you are introducing is more risk, more work, and zero benefit. No matter what you do to your WM it is not going to outperform my Lott where it counts, in the bush up close and personal with a big ugly.
 
I think the elephant in the room, in regards to all of these pictures posted of bullets being seated way out, is the fact that I would never take this ammo on an actual DG hunt. A bullet seated so shallow in the case seems to be a disaster waiting to happen.
I have seated some bullets out a bit in my 458 Win Mag, but nothing as extreme as some of the pictures above. IMO, exceeding 458 Lott COL isn’t needed for hunting. But I suppose it’s ok for range work, where you’re just trying to get the most velocity possible.
+1. I've never hunted DG, but if/when I do I'm sticking with factory Lott or .416 Rigby ammo. I've only reloaded for my .458WM and .416 Taylor so far in big bores and I personally don't feel comfortable bringing my reloads on DG hunt. I definitely wouldn't hunt DG with reloads with extended COAL. Murphy tends to follow me around a lot. LOL
 
IMG_8304.jpeg


BTW Saswart, I added 0.5gr N540 extra powder to my Lott load and with the heat of this Saturday's shoot it produced 2319fps over the Labradar. Overall Cartridge length is 92.6mm or 3.65" rounded off

Reason being for adding extra powder now my 500gr SBC softs and the Impala brass solids print 0.5" apart at 30 meters. The SBC soft bullet runing at 2240fps and now the solid at basically 2300fps if you take the high temps of Saturday out of the parameter.

I am very pleased with my Lott and it does what it was intended to do so on DG and is fun to use on plainsgame. As long as you restrict yourself to 150 meters max range on larger game.
 
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View attachment 649774

BTW Saswart, I added 0.5gr N540 extra powder to my Lott load and with the heat of this Saturday's shoot it produced 2319fps over the Labradar. Overall Cartridge length is 92.6mm or 3.65" rounded off

Reason being for adding extra powder now my 500gr SBC softs and the Impala brass solids print 0.5" apart at 30 meters. The SBC soft bullet runing at 2240fps and now the solid at basically 2300fps if you take the high temps of Saturday out of the parameter.

I am very pleased with my Lott and it does what it was intended to do so on DG and is fun to use on plainsgame. As long as you restrict yourself to 150 meters max range on larger game.
Your photo shows cartridges with three different case lengths. Is this a quiz? LOL
 
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As mentioned elsewhere 458 express, 458 Lott, 458windbag
Gumpy
Thanks! I didn’t see the description included with the photo. That express cartridge must really rock and roll compared to the Lott?
 
Does a critter know if it got hit a 450 grain bullet going 2200 fps or one going 2350fps?
With well placed shot… nope dead critter.
When you screw up the shot then you might very well be screwed up. No matter how fast that bullet was going.

But I will say that it does make for some interesting reading.
 
Does a critter know if it got hit a 450 grain bullet going 2200 fps or one going 2350fps?
With well placed shot… nope dead critter.
When you screw up the shot then you might very well be screwed up. No matter how fast that bullet was going.

But I will say that it does make for some interesting reading.
What about 500gr or even 550gr at 2300fps vs 450gr at 2200fps? Assuming of course the same bullet design abd caliber.....
 
I think the elephant in the room, in regards to all of these pictures posted of bullets being seated way out, is the fact that I would never take this ammo on an actual DG hunt. A bullet seated so shallow in the case seems to be a disaster waiting to happen.
I have seated some bullets out a bit in my 458 Win Mag, but nothing as extreme as some of the pictures above. IMO, exceeding 458 Lott COL isn’t needed for hunting. But I suppose it’s ok for range work, where you’re just trying to get the most velocity possible.
The ones I posted are only to show the throat differences. Dummy rounds to check individual rifle throats.

There are significant differences in individual factory 458 Winchester throats, and factory individual 458 Lott throats. None of those are the same. Which of course influences individual rifle velocities and psi.

Hell, certain bullets will not even be in the brass to reach the lands of certain rifles.
 
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Thanks! I didn’t see the description included with the photo. That express cartridge must really rock and roll compared to the Lott?
Not really the express was built as a result of lack of powders available in South Africa and the extra space allowed for slower burning powder with less pressure which resulted in less recoil with same speed.
 

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(cont'd)
Rockies museum,
CM Russel museum and lewis and Clark interpretative center
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Good Morning,
I plan to visit MT next Sept.
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Start in Billings, Then visit little big horn battlefield,
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