View Full Version : 6.8 or .450 Upper on 5.56 Lower?

Cru Jones
01-13-2009, 9:18 PM
In my search for something with a little more stopping power/penetration than the .223 round, I ran across a few 6.8mm and .450 upper assemblies. They didn't specifically say they can be used on 5.56 lowers but they did say "fits standard lowers."

I was hoping someone who knows about these uppers can confirm they will fit on a 5.56 lower.

I have two 5.56/.223 rifles assembled already and have another lower or two lying around. I'm looking to do something different with those.

Any thoughts, ideas, input is greatly appreciated.

01-13-2009, 9:29 PM
They will fit on a .223/5.56mm lower.

01-13-2009, 11:47 PM
You might also want to check out 6.5 Grendel, .458 Socom and .50 Beowulf, depending on your needs. They all fit AR-15 lowers.

01-14-2009, 12:00 AM
6.5 Grendel is cool stuff...

01-14-2009, 2:40 AM
6.8 spc is the **** if you dont mind 20.00 for 20 rounds.

01-14-2009, 2:43 AM
I have the 1/10 twist stag wich is the not so good version but i shot 1" 3 shot groups at 100 yards on my first time at the range not to mention it was my first time shooting an ar 15. The 1/11 or 1/12 twist should be even better. If you really want one check out titan armory and their extreme 6.8 upper.

01-14-2009, 10:28 AM
Go with the Grendel. From what I understand the 6.5 has the edge over the 6.8 SPC in just about every way possible. And as others have said, yes those uppers will fit on the 5.56 lowers.

01-14-2009, 12:17 PM
I think I have a complete 458 Socom upper left if anyone wants one.

01-14-2009, 12:21 PM
How much? I have a second AR that I might want to swap it over to.

Cru Jones
01-14-2009, 2:00 PM
Thanks for all of the suggestions. There is way more options out there than I thought.