458-338 Lapua

Jimbob

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I saw that PTG do a chamber reamer for this cartridge and it got me interested.
I made the cartridge on QuickDesign (QD) and put the case capacity and other info into QuickLoad (QL). Obviously all these are estimates.
Anyway, QD reckons it would have 122gr of water compared to the Lotts 110gr. Working off this suggests max loads near to 2450fps with a 500gr. However what got me interested is that you could get Lott velocity at lower pressure and 450NE velocity is even lower pressure.
All this from readily available brass of good quality whilst having no belt. The only downsides I can see is that you would lose a round capacity likely as not and if you housed it in a CZ550 416 Rigby the cartridge wouldn't make full use of the action length (although this would mean you could seat bullets out as far as practical).

Any thoughts?
 
would there be enough shoulder left to safely head space the cartridge? you would likely have to do more then just neck them up, probably blow out the taper in the case body as well.

-matt
 
It works out a fraction more than 35 whelen so shouldn't be an issue but it is a minimal shoulder. That been said, it's better than my 9.3x57 :D
 
I do like your thinking though, a blown out case would have more to headspace off. Feeding wouldn't be as smooth though I wouldn't imagine.
 
Be expensive to obtain proper headstamped brass. I'm having that issue now with my 375 whelen improved. I want to take it over hunting but killing me getting headstamped brass.
 
I saw that PTG do a chamber reamer for this cartridge and it got me interested.
I made the cartridge on QuickDesign (QD) and put the case capacity and other info into QuickLoad (QL). Obviously all these are estimates.
Anyway, QD reckons it would have 122gr of water compared to the Lotts 110gr. Working off this suggests max loads near to 2450fps with a 500gr. However what got me interested is that you could get Lott velocity at lower pressure and 450NE velocity is even lower pressure.
All this from readily available brass of good quality whilst having no belt. The only downsides I can see is that you would lose a round capacity likely as not and if you housed it in a CZ550 416 Rigby the cartridge wouldn't make full use of the action length (although this would mean you could seat bullets out as far as practical).

Any thoughts?

I would stick to the 450 Rigby, it will do more if needed and no issues with head stamped brass which is be a problem in Africa. The 450 Rigby is a superb DG cartridge.
 
Yeah I thought about the headstamp. One could easily fit a '45' before the .338

IMG_7964.JPG
 
Last edited by a moderator:
Would be easier since it just takes a CZ550 in 416 Rigby and a new barrel. However, my long term doodling project uses a detachable mag (controversial I know) and 5 shot mags in 338 Lapua are prevalent.
That been said, a 450 Rigby would fit in a 338 Lap Mag magazine (mags have 3.77" internal and the Rigby is 3.75")
Lapua 338 Lapua brass is half the price of Bertram 450 Rigby brass mind and Lapua makes excellent brass.
 

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