NO!!!!

A Lee crimp die will NOT "crush" ANY heavy jacket OR monolithic .458" bullet designed for heavy or dangerous game!

In a single-shot there's NO need to crimp!

I know because I used a Lee crimp die in both .45-70 AND .458 Win Mag.

In .45-70, with softer bullets, it will work in creating a slightly indented ring around the bullet, and that does help. In bullets designed for game like Cape Buff, they DO NOT create a simulated cannelure, but they do create a bit more pressure at the case mouth. I like them in the .458 WM with a long box, like a CZ, as the mouth of the case is slightly beveled in toward the bullet as a result (no sharp edges). I also use one in .45-70 for my Ruger #1 in .45-70 Improved (long-throated) where heavy bullets can be seated "long" to match a .458 Win Mag. BUT, pressure from the cartridge-case in gripping the bullet on a slightly COMPRESSED LOAD is a must to keep the loaded cartridges UNDER the first, in a magazine rifle, from having their bullets pushed back into the case under heavy recoil, if there is no ready-made cannelure in which to crimp. Barnes' TSX's and Banded already have several cannelures (bands) where one may crimp (as does North Forks and others)if a longer COL is needed or desired, and assuming the throat and magazine allows for it. (I've written a manual on this.)

Bob

www.bigbores.ca