Home Forums Hunting & Shooting Express Rifles and Big Bores Only The great 458 Winchester. Everyone should own one at least once

Here is rough visual comparison at a glance for those who like pictures, like I do:



In quickLOAD the default case capacities of the .458 WM-2.5" and .458 Lott-2.8"
are 95 grains and 110 grains of water respectively.
No allowance for throat.
Here is the allowance for throat:
The SAAMI .458 WinMag has 0.1582" greater length than the SAAMI .458 Lott
from breech/bolt face to first contact of a .458-caliber bullet with rifling of .458"-groove diameter.
A right-cylindrical bullet of .458-caliber displaces 41.66 grains of water for each inch of its length.
Thus the SAAMI .458 WM has a "throat-actualized" effective capacity of 6.59 grains of water greater than the SAAMI .458 Lott.
So consider the SAAMI .458 WM to have 116.59 grains H20 gross and 2.5" brass length
when calculating pressures and velocities with quickLOAD, for comparison to the same calculations for the SAAMI .458 Lott.