Looking to build a large caliber AR and was wondering what you thought of these 3 and the good, bad, and ugly so to speak

I would look at the cost of ammunition and/or reloading supplies. I dont think there is a significant difference between them.

I like the fact that the .458 Socom uses standard 5.56 mags

Im not too worried about ammo cost, they are all roughly the same cost wise, Im not going to be emptying mags much, and I plan on reloading

I run standard mags all day long in my 50 beowulf...

That being said if you consider other things like availability and cost of bullets... 45 cal are much more friendly than 50s... and when you think about the use of a can for more than one "gun" a 45 can could cover quite a few uses.. a 50 not so much.

Been a while since I read up on them but seems like one of the advantages of the bushmaster was being able to make use of all the bullets designed for the 45-70. Loaded up with the polymer tipped Hornady's (FTX maybe?) that would make a bad ass deer thumper.

I thought the SOCOM used .458 and the Bushie used .451. Or something like that.

the SOCOM is .458. It is often compared to the 45-70 in killing power, and would be my choice. RRA makes complete uppers and there are a few different ammo companies loading it. I believe the 50 is a proprietory cartridge and chamkbering. Alexander Arms is the only source IIRC.

50 Beo barrel/bolt combos can be bought from Midway via the Stoner brand, or at the A.Arms website. 50 is going to be the most expensive overall to buy/shoot

I think 458 Socom is pretty much a reloading only (may be wrong)

450 bushie has factory ammo, but for that price you can buy dies, IMHO.

I have a DPMS LR-308, so for the cost of any one of these uppers, I can build on in 338 Fed., should I get the urge

The real ugly is the cost and availability of brass. It sucks being stuck with specialty brass that can't be formed from more common brass and finding out nobody has the brass in stock. I'd look into brass availability before making a decision, and however much brass you think you'll need, get twice as much.

i have the 458 socom. reason: i have a 16 inch barrel in 45/70 for my encore and when i get a can it will work with both. the 450 bushmaster is .451/.452 diameter, don't have those bullets but i do have .458 diameter bullets. factory ammo and brass is available for all three "sometimes". just have to buy up a supply when it can be had.

So the 45/70 uses .458 bullets? I was bassackwards then.

Since 1866

Don't know where I got it in my head it used .451. Guess I'll change my wish list to the SOCOM.

I have a 450 Bushmaster and the deciding factor for me was the cost and avaliblity of the ammo. I didn't see enough ballistic performance difference to justify the additional cost for the rifle itself.

This thing will stop just about anything at 200 yards or less

There is no replacement for displacement. A .458 bullet traveling the same speed as a .410 bullet will make a bigger hole and break more things.

Maybe that's why the 450 bushy doesn't stop EVERYTHING at 200 yds or less.

Great info guys, thanks

I think I am going to go with the SOCOM

Now, if someone wants to donate an upper.....PM me

I ended up with the 450 bushie.

Glad i did too.
I had my doubts for a time until Remington started makin the ammo for it also.
now only that, its the same brass as another popular round I cant remember rite now. Its just cut down.
Same dia. Projectile as the .45ACP as well.

Accurate. Deadly.
Not something I dont wish to shoot every day...