Home Forums Hunting & Shooting AR and Tactical Rifles 450 Bushmaster or 458 Socom?

Which is the better build? Pros and cons? Ammo availability? Reloadable? Can the bolt face or bolt be used for other calibers? If so what?

If I were buying over again, IE didn't have a beowulf.... I"d be looking hard at which one shot pistol bullets for cheap plinkers...

I don't recall which one that is right off the top of my head.

The 458 Socom can shoot 4570 bullets. The 450 Bushmaster, I think shoots 45 long colt bullets. I think the 450 Bushmaster is 0.420 diameter bullets and the 458 Socom is 0.458 bullets if I remember correctly. 50 cal bullets are harder to find, only other 50 cal is the 500 S&W pistol bullets.

correct on the bullets used.
i have a 458 socom and like it. but then i have been shooting the 45/70 for near 50 years and always have plenty of 458 bullets. i cast both size 45's and could have gone the 450 route but just happened to get a package deal with the 458 i wanted.
the socom is a very impressive round that fits in standard 556 mags. i am not sure about the bushmaster

Deerstalker, I also have a .458 SOCOM. I made that choice due to having both a .45-70 and a .44 Magnum. I use the bullets I have for the .45-70, and the powder/primer that I have for the .44 Mag. The only thing I had to buy was the cases and dies.

I didn't even have to buy a shellholder, it uses the same one as my .308/.243/.30-06/.45 acp.

Logistically it was an easy choice for me.

The only powder I've tried in it is H110, but I want to try some Lil 'gun (which I use in my .44 mag rifle), and possibly some IMR4198 with some heavies.

To the OP, the .458 does not require special mags or mods to the lower. I think the only real mods required are opening the ejection port and the boltface obviously has to be opened. It functions best with a carbine-length gas system.

I don't know that much about the other cartridges, but I can't imagine there are any *real* field performance differences. I suppose that bullet choice would be the most important.

I do know the .458 does have some "whomp" factor to it.

I went .450 Bushmaster. I "wanted" a 500 but even calling this a total frivolous purchase I couldn't' do it.

Brass gets lost too easily and I didn't want to have to fight trying to find .458 SoCom or .500 Beo.

Ammo is a tad cheaper and there's absolutely nothing wrong with a 300gr. XTP reload at 1800 fps.

What sold me though were some of the range reports of the .450 being MOA capable. Damned if my 20" .450 didn't rip a single, golf ball sized hole at 100 yards.

I'm not sure I'd hunt with the 250 Flex Tip but it's been done successfully on deer and hogs. personally, I'd like something just a bit heavier and that's why I'm looking at the XTP or a hefty WNFPGC.

Regardless, ZERO regrets on the .450 Bushmaster. It is a proper thump.

rnovi. i have used the 250 gummie tip on elk out of my 95 marlin 45/70 for years now and never had one go over 50 yards.
i have also used the WNFPGC for close to 50 years for the times i will be in grizzly areas. they work spectacularly on big Blackies so i have faith that they will ruin a griz's day too.
vic, i have used 4198 with heavies and had good results.
am getting weaker and the 458 makes me hurt for several days after anything over about 20 rounds. may have to pass it on soon.
i load some 405g cast powder coated with great results.

Thanks for the comments on the 250. Very glad to know that!

Not correct. The 450 Bushmaster uses .452" bullets, not .420" bullets.

Ok so 0.452 bullets are not as widely available as 0.458 bullets. Point being, seems to me the Socom would be easier to reload for.

I just finished building my AR-15 .450Bushmaster. I look forward to tapping your collective knowledge base, once i get reloading equiptment.
From my limited perspective, i could see no diffrence between the .450Bushmaster and the 45-70 shooting next to me at the range bullet wise, other than the 45-70 was a bit longer. Everything else seemed identical. I collected some of his brass along with mine when i sighted it in.

I have the 458 socom. It shoot .458 bullets. The 450 uses 452 pistol bullets (same as 45 colt 454 casull). That is a plus for the 450 because these AR rounds are all in the same class as magnum pistol rounds. On paper (wiki) the socom is slight more power than the other two. The 50 Beowulf is obviously the largest bore. I think two top out just under 3000 ft-lbs energy (2800). The socom tops out at 3300ft-lbs on wiki for first place edge. I like 458 socom cartridge design with a shoulder to head space. And, I like the 458 bullet selection.

I would say the three are about the same, because there is only so much you can fit into and AR15. The real difference, IMHO, turns out is the bullets. Brass is easy to find for all three, if you go online. The 450 probably has the bullet availability edge (pistol bullets). Socom in 2nd place for bullet choices. Unless you want subsonic blockbusters. The socom has the hvy bullet edge. Or suppressed, the socom. The 50 has the big-bore braging rights edge and probably least selection of the most expensive bullets. I have on occasion seem loaded 450 ammo on LGS shelves, never the other two. That was fair priced Hornady 450 ammo.

If you consider reliable feeding with good hunting performance, there is probably a very limited selection of good polymer tip bullets for any of these rounds.

The 450 seems like the only one of the three that does not have some kind of license or proprietary issues. No voodoo secrets. Given a choice of Alexander 500 or rock river 458, I choose RRA. Easy choice for me. I image the 450 is available on a wider range of platforms and easier to build with proper spec parts.

Edit: I may be mistaken on the 450 bushmaster status. Quote from wiki:


This would make all there big boys a pain in the proprietary butt.