https://www.thefirearmblog.com/blog/2015/07/06/oood-mccann-industries-458-win-mag-garand/

Byron

Great for Michigan deer .

It does look like a very cool toy.

I wonder what they did about the op rod bending/cracking? I've read that even heavy .30 bullets can cause damage to a standard M1 op rod.

Heavy duty op rod and little bitty gas port, maybe?

pressure, likely similar, op rod does not touch bullet, only gas. But, as you point out, even modern SAAMI .30-06 3000fps is far over original M1 ammo at 2700fps, same as .223 vs 5.56mm in tearing up a gun designed around lower pressure.

and max on M1 ball was up around 57kcup? Take more digging than I am gonna do for a gun I will never own, nor would want to ruin sweet Garand low recoil memories by shooting.

I'm not sure it is related to max. pressure of the cartridge but what the pressure is when the bullet passes the gas port. I have no idea how that would compare but with handloading maybe it could be made to work.

at least according to the LA Silhouette Club web page.
And with the shape of the 458 cartridge and big barrel bore I think that the pressure would fall faster as the bullet goes down the barrel than it would for a 30-06.

Little things that take it from breaking an oprod, to, I wonder if enough juice is there to cycle the action. Gotta take into account recoil of gun slowing relative oprod movement, as well.

Still wrecks the most comfy high powered rifle ever made, as for my tastes, but, very cool, anyhow.

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