.458 WM to .458 Lott

I would chat with Ian Sweetman, or J Roberts and Sons. Ian is building lots of nice big game rifles, Roberts have a very long history of doing so. The re chambering is, I believe, the easy part. Getting it to feed from the magazine is more tricky, but absolutely essential in a Dangerous Game rifle. And there is a big difference between feeding OK provided push the bolt forward at exactly the correct speed, to feeding when have something big a grumpy wanting to stomp and bight you and that bolt is being worked in a hurry, or even worse its been sent flying but said grumpiness and a very scared tracker has to pick it out of the dirt and work the bolt to save his and your hide.
 
It may be that with today's modern powders (not avaiable in the past) that you can get the same performance in the standard .458 WM case if you are allowed to use handloaded cartridges? My first port of call might be to put the rifle over a chronograph?
 
From the internet re modern make factory ammunition that uses powders that didn't exist in the past:

Hornady offers what they call a "heavy magnum" loading, which features a 500 gr (32 g) bullet with a velocity of approx 2,260 ft/s (690 m/s). They use a special double-based cooler burning propellant ("powder") not available to the public.
 
It may be that with today's modern powders (not avaiable in the past) that you can get the same performance in the standard .458 WM case if you are allowed to use handloaded cartridges? My first port of call might be to put the rifle over a chronograph?
There was never much in it anyway. Was the .458wm really a handicap?
 
I would chat with Ian Sweetman, or J Roberts and Sons. Ian is building lots of nice big game rifles, Roberts have a very long history of doing so. The re chambering is, I believe, the easy part. Getting it to feed from the magazine is more tricky, but absolutely essential in a Dangerous Game rifle. And there is a big difference between feeding OK provided push the bolt forward at exactly the correct speed, to feeding when have something big a grumpy wanting to stomp and bight you and that bolt is being worked in a hurry, or even worse its been sent flying but said grumpiness and a very scared tracker has to pick it out of the dirt and work the bolt to save his and your hide.
Its a CZ550, think it is a straightforward chamber lengthen?
 
07768 261717
This chap my be able to help. He is based in Detling Kent. I looked at a 458 Ruger No 1 that he had changed to .458 Lott.
 
Norman Clark in Rugby was happy to do one for me a few years back. In the end I never had it done. I decided to go with slightly lighter 450 grain bullets and seat them out further to make use of the long magazine box length and long freebore. No chamber work or reroofing needed and velocities up there with the Lott.
Is this a new rifle to you? What’s the plan with it? Buffalo?
 
Why?
The beneifts are largely theoretical

In real terms you are talking 100-150fps difference in MV for the same bullets for a huge powder increase

Done a fair amount of loading and research into the 458WM recently

its a similar discussion around 416RM and 416 Rigby
You can get some snappy ammo out of the H&H cases


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I’m not an expert with large bores by any means but I think the Lott was developed due to having to cram too much old fashioned powders into the wm case to get the target velocity which then over time clumped together and caused hangfires ect. I think these issues have been resolved with modern powders so the wm is now just as reliable as the Lott.
 
Dennis Blackbeard, swore by the 458, always said it sat stuff down just fine, mind you the Lott wasn't about in 1959 I don't think.

David.
 
I truly love the .458s. There is a definite difference between the 458 Win Mag and the 458 Lott. I have had many people shoot my 8.5lb 458 Win Mag, no one has refused a second go. With the scoped 458 Lott that weighs 11lbs it is fairly common for people to say no when offered another few shots. 500 grain full house factory loads are quite snappy! I think for many people there is a line in recoil that is crossed between these two cartridges. Saying that when using it in the field the recoil becomes a non- event and I invariably see my strikes. Off the bench both the Win Mag and the Lott are unpleasant, from prone they are painful!
Here are some recovered bullets from my recent trip. The bullets (450grain Barnes TSX) and 300 grain Barnes TSX were recovered from Cape buffalo, hippo and giraffe. I did fire some 450 grain solids this year and last but have never recovered one yet.
 

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Why?
The beneifts are largely theoretical

In real terms you are talking 100-150fps difference in MV for the same bullets for a huge powder increase

Done a fair amount of loading and research into the 458WM recently

its a similar discussion around 416RM and 416 Rigby
You can get some snappy ammo out of the H&H cases


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Does this mean you are going to stock 458 calibre Peregrine bullets??? 😁
 
I think the problems with the 458 WM stemmed mainly from the way they were used with powders of 60 to 70 years ago.

In them days in Africa soon after independence of most countries ammunition was all but impossible to get. Ammo got stored and horded in all sorts of places usually in tin boxes. And Africa is hot, and most ammo should be kept in a cool place. A few years of such storage then degrades the ammo somewhat.

Then the 458s were carried by National Parks Game Scouts and PHs. They were only really used on culling operations of Elephant or as a back up rifle. So most cartridges, once they had come out of their cartridge box, spent the rest of their life being bounced around in a land rover or carried in the magazine of the rifle - all in 40°C.

If a shot was fired the magazine was simply topped up. Most game scouts and phs in those days carried their rifles loaded and even in camp they were loaded. Last thing at night if you have a big four legged or dangerous two legged animal close by with evil intent is to be scrabbling around looking for cartridges.

Very rarely if you did shoot would you need more than two or three shots.

So that cartridge at the bottom of the magazine could have been there for many months and subject to all sorts of heat and vibration. All leading to powder degradation and imperfect performance.

A properly loaded 458 with fresh cartridges should be more than adequate for any African animal.

Rather than spending lots of money on having it turned inti a Lott, use that money instead on ammo learning how to shoot it.
 
I’ve only owned one 458 Win Mag and it was a Ruger #1H I shot it a good bit at 50 and 100 yards both unscoped and scoped . It wasn’t bad and shot really well with handloads but I like the 416 REM Mag more . About the time I acquired the #1 458 we had a Win Model 70 Safari that had been run out to 458 Lott I took it out and test fired it with handloads that had come with it and the thing shot very well from the bench but after a dozen shots I was a bit shell shocked . I think if I’d acquired it any further shooting would have been three shots wait an hour repeat . Kinda the way I handled things when working up a load and sighting in a CZ550 in 505 Gibbs for a friend .
 
I’ve only owned one 458 Win Mag and it was a Ruger #1H I shot it a good bit at 50 and 100 yards both unscoped and scoped . It wasn’t bad and shot really well with handloads but I like the 416 REM Mag more . About the time I acquired the #1 458 we had a Win Model 70 Safari that had been run out to 458 Lott I took it out and test fired it with handloads that had come with it and the thing shot very well from the bench but after a dozen shots I was a bit shell shocked . I think if I’d acquired it any further shooting would have been three shots wait an hour repeat . Kinda the way I handled things when working up a load and sighting in a CZ550 in 505 Gibbs for a friend .
Now that is a "stopper".

David.
 
An excellent article by Craig Boddington. He discusses the 458s. In his view with modern propellants and the slightly lighter bullets (400 as opposed to 500gn) he opines no reason not to use it.

I lived in Zambia in the early 1990’s. Ammo was pretty much non existent. There was the odd Indian store that had a box or two and you bought cartridges individually. I had use of a 375 for protection - just 4 cartridges with it. I never bothered carrying it.

Only ammo that PHs had was what left behind by hunting clients.

 
Vihtavouri with N130 to N135 powders show a good number of loads with various 400 to 500 grain bullets getting the 2150 to 2250 fps velocities that the 458 originally made putting it on a par with the 470 Nitro Express


And an article on reloading the 458 wm, albeit from a US perspective with powders unavailable in the uK

 
I have found RS40 to work exceptionally well in both the 458 Lott and the Win Mag. My standard load in the Lott is a 450 grain TSX at around 2300fps. For cheap practice I use a 405 grain jacketed 45/70 bullet from PPU. In the UK I think RS40 is one of the better choices for these calibres. One significant problem that I have found is that quality hunting bullets seem harder to find compared to .375 and possibly even .416. There are only a small number of dangerous game worthy bullets anyway, and some options like the swift A frame have generally poor availability. Barnes TSX are about the most available of the top tier bullets but after that the choices dwindle to Hornady DGX which has a sullied reputation. We really need a reliable mechanism to get more options in the UK such as the Swift A frame and breakaway solids, North Fork, the Peregrine, Cutting Edge bullets Safari solids (I don’t like the Raptor) and the Rhino bullets.
 
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