458-338 lapua? Anyone done this?

[CoElkHunter]

To clarify, the B&Ms are improved and constructed using RUM brass, not WSM. Not to derail the OPs thread.

You're right. My mistake. The B&Ms are designed to be used in a Winchester M70 .300WSM action but use the RUM cases.

 

[kfreeze]

To clarify, the B&Ms are improved and constructed using RUM brass, not WSM. Not to derail the OPs thread.

I was thinking of stuff off of an 300 ultra case too. Mostly 416 or 375 is what I had pondered. But I really want something in .458 for some reason.

 

[jwp475]

Isn't the 450 Rigby the 338 Laupa necked to .458

 

[Jefferry404]

The Rigby case is 170/1000” longer and psi rating
Is 15% lower. It’s OAL is 3.75 vs the 458/338 would be at 3.429, I guess trying to get rigby performance in a shorter package.

 

[Jefferry404]

@kreeze
if okay iwth you, thinking to start another thread on the 458/338LPM in a Ruger Hawkeye platorm

 

[CoElkHunter]

@kreeze
if okay iwth you, thinking to start another thread on the 458/338LPM in a Ruger Hawkeye platorm

Would the OAL 3.429 fit into the long action Hawkeye platform? And, can the .532 bolt face be opened up to the .588 of the Lapua case? Thanks!

 

[Jefferry404]

the OAL is just at max (Ruger mag box is at ~3.45". With Hyd 480 DGX is 3.439" and with Bar 450 TSX at
3.367". The case might need to be trimmed a hair, depending upon the length after fire forming (I used 26/1000" case shrink per the wildcat wizard).
The Ruger bolt is 0.690" diameter, so would think the 0.588" fits (CZ550 magnum has 0.700" bolt and the 0.640 case head of the 505 Gibbs fits that, abeit with little margin.

 

[Jefferry404]

so i guess the idea would be a std length cartridge for DG with more oomph than the current 458's.
@jwp475 the 458/338 normalized to the 450 Rigby Norma data,
shows for the same pressure, 55102psi, the Rigby has 2159fps vs the 458/338 has 2117fps. That was near max. for the Rigby.