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
 
Last edited:

Forum statistics

Threads
57,939
Messages
1,243,412
Members
102,368
Latest member
Brandontheresa
 

 

 

Latest profile posts

Grz63 wrote on Werty's profile.
(cont'd)
Rockies museum,
CM Russel museum and lewis and Clark interpretative center
Horseback riding in Summer star ranch
Charlo bison range and Garnet ghost town
Flathead lake, road to the sun and hiking in Glacier NP
and back to SLC (via Ogden and Logan)
Grz63 wrote on Werty's profile.
Good Morning,
I plan to visit MT next Sept.
May I ask you to give me your comments; do I forget something ? are my choices worthy ? Thank you in advance
Philippe (France)

Start in Billings, Then visit little big horn battlefield,
MT grizzly encounter,
a hot springs (do you have good spots ?)
Looking to buy a 375 H&H or .416 Rem Mag if anyone has anything they want to let go of
 
Top