.458 SOCOM 400GR Recoil Impulse

[pratchett]

It seems widely accepted that .458 SOCOM cartridges in the 400 grain range produce an uncomfortable recoil impulse, but those in the 300 and 500 grain ranges are much more pleasant. Can anyone explain the science behind that?

[elSquid]

[woolybugger]

Are you saying 400 grain projectiles have more recoil than 500 grain projectiles?
This seems counter intuitive to me but i have yet to finish my 458 socom build.

[jamie404]

Are you saying 400 grain projectiles have more recoil than 500 grain projectiles?
This seems counter intuitive to me but i have yet to finish my 458 socom build.

Well the amount of space the entire cartridge can take up is fixed. So it is a battle between bullet size and powder volume.

[seal20]

400gr IS between 300gr and 500gr

[CoopsDad]

I shoot 350 grain JSPs out of mine; I have no brake, just a thread protector. It's a hammer down range but it's also pretty heavy hitting on the firing line, too.

[sigstroker]

It's possible. It could be that you can't get enough powder in with a 500 gr bullet to get as much energy as with a 400 gr bullet.

[pacmule]

[Sam .223]

Ive been shooting 350 grn out of my 458 and it kicks about the same as a 12 guage, its not to bad but it does wear on your shoulder after a while.

[jeremyro]

You really get the most force downrange in the 300 grain range with this cartridge. I can imagine that by the time you hit 500 you are pretty short on powder space.

[NATO762]

.458 muzzle energies. All are SBR brand, JSP or JHP

300grain:2256 ft/lb

350grain: 2116 ft/lb

400grain: 2021 ft/lb

500grain: 1066 ft/lb

IIRC, ~350grain is the optimal load. The 500grain are almost all subsonic. It really depends on how the 300-350grain projectiles are loaded.

[naz]

What muzzle devices are you guys using? Mine came with the Kaw valley linear comp and I’m waiting on ammo and reloading supplies to try it out

[Sam .223]

I'm using this one.

https://www.midwayusa.com/product/1020533778?pid=944697

[pratchett]

It's possible. It could be that you can't get enough powder in with a 500 gr bullet to get as much energy as with a 400 gr bullet.

That's a really interesting idea! I'd never thought of that. So 400 has more recoil than 300 because, yeah. And 500 has less felt recoil than 400 due to less powder. Can anyone who reloads comment on this Idea?

[NATO762]

That's a really interesting idea! I'd never thought of that. So 400 has more recoil than 300 because, yeah. And 500 has less felt recoil than 400 due to less powder. Can anyone who reloads comment on this Idea?

Look at the muzzle energy drop off between 400 and 500 grain, it's almost half! The powder is maxed out, but they can't get the projectile above the sound barrier. I don't reload, but the reload charts are out there.