.458 B&M Winchester-throated Fast Twister

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7 pounds 2 ounces without the scope and rings.
8 pounds 14 ounces with the fun little 2.5-10x56mm Mildot "Eurolux" 30mm tube in medium height Burris XTR rings.

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The .458 BMW is a .458 B&M retrofitted with a SAAMI .458 Winchester Magnum throat.
This one has a 1:10" twist Pac Nor barrel 19.75" long, on a Connecticut Classic M70 300 WSM action.
A .30-'06-length action and a longer barrel would be a further improvement,
but as is, when loaded single-shot style, it will serve for extrapolation purposes to mimic a fast twist .458 WM+.
The .458 BMW at 3.340" COL is equivalent to a .458 WM+ at 3.600" COL,
with any bullet long enough to be loaded in both.

Interstingly, the .458 B&M in its short-throated proprietary version has a maximum brass length of 2.250", trim to 2.240".
The .458 WinMag has a SAAMI chamber length of 2.520" for brass length accommodation,
so a trim-to-length of 2.500" is appropriate for the .458 WM+, max brass 2.505".
The .458 BMW should maintain a trim-to length of 2.240".
The .458 BMW is 0.260" shorter in brass length than the .458 WM+, 2.240" versus 2.500".
The two cases have the same gross capacity at these lengths when both utilize R-P brand brass.
It is not surprising that both also have the same net capacity when the .458 BMW COL is 3.340"
and the .458 WM+ COL is 3.600".
Both are capable of opening a can of whoop ass on the SAAMI .458 Lott.

Ron aka "Rip" for Riflecrank Internationale Permanente
NRA Life Benefactor and Beneficiary
.458 Winchester Magnum, Magnanimous in Victory
THE WALKING DEAD does so remind me of Democrap voters. Donkeypox.