AR 10 .308

[CANNONMAN]

I want to help build an AR10 in .308 for a friend. I've built several AR 15's in pistol and rifle in .223 and .300BO. Now I've got a buddy who wants me to put a really nice .308 together for him. I've asked a few questions here and got some great info. Here's where I am now. A Krieger 22" barrel is made. Krieger says they will only place a JP BCG on their stuff. OK. But, why would I want a low mass vs full mass BCG? My buddy has supplied his own upper and lower. These I'm told are DPMS clones. OK. So do I have a large frame? How do I tell? I've picked out a Gelssele 2 stage trigger. He wants to target and hunt. The first stage is 2.5# and 2# for the second. This seems to make sense. I want to build the brake. Though I'm not positive this is the best idea. The ones I've made have reduced recoil and enhanced accuracy but I do not know how they stack up to any of the myriad of brakes out there. Krieger mill matches the brake to the barrel. This looks great when I've done this. No crush washer. He has a stock, the lower kit. I've got a hand guard. The build is supposed to be right at $1,600. I'm really close. Thoughts?

 

[Gordon]

Adjustable Jp gas block and get the matching JP buffer system if you are using their BCG . Watch the pin sizes in the lower kit he bought, deal with it if there is a problem. Good luck.

 

[Varminterror]

Krieger only uses JP bolts. You can use any BCG you want behind the bolt. They are different parts. Maybe Krieger does provide BCG’s, but I’ve never gotten anything but a bolt from them.

Most likely his upper and lower are Gen 1 DPMS pattern, not Gen II, as I don’t think many places (any?) are making GII clones. The height of the top rail is the give away. High is the Gen 1.



Krieger will also throw a standard thread tenon, or no threading if you want to do your own brake blending.

 

[mshootnit]

"you can use any bcg you want behind the bolt"

bcg stands for bolt carrier group.

 

[Gordon]

True on the bolt called out for versus the BCG . Yes the JP BCG is "low mass" and you should use their buffer set up IF you use it. If you don't be double darn sure to use the correct AR10 length Buffer in certain stocks , springs too. I personally think an adj gas block on an AR10 is very wise. Like I said the pin sizes in the lower kit can be weird, be careful. The non gi type trigger assemblies need to be watch ed certain lowers , metal may need to be removed .

 

[Matt.Cross]

Nomenclature can cause you issues. As best you can, stick to a definitive pattern in your parts. "AR-10" is itself an Armalite designation, although it gets applied as a general term for large frame ARs. If you are basing your build on a DPMS patterned receiver, sticking with DPMS compatible parts will result in fewer headaches. Same is true of an Armalite pattern build, Armalite pattern parts throughout will generally yield fewer headaches than mixed grab bag builds.

In short, don't be tricked by the AR-10 misnomer. Find out what type of pattern (s) your parts will be compatible with, and stay as consistently as possible with a single pattern, and you'll come out fine.