View Full Version : AR-10 question for build

04-22-2012, 8:02 PM
Hello Calgunners-

I have a POF-USA P-308 stripped lower and it is stamped .308 caliber as I expected. I have found a complete POF-USA 20" upper but the barrel is stamped 7.62 with a 1/10 twist rate. Are these compatible? Will only .308 ammo work in the upper?

Ill be anxiously awaiting information.....



04-22-2012, 8:13 PM
Whatever the lower says is not important, it's the barrel that counts.

They say not to use 308 in a 7.62, I've shot hundreds of 308 rnds in my 7.62 rifle w/o a single problem. My 7.62 that's on order with Larue, they said it's fine using 308 in their 7.62.

04-22-2012, 8:20 PM
The stamping on the lower really doesn't matter. The barrel is 7.62x51 and on POF website is they are all listed as 7.62x51 (308 win).

.308 Win is generally hotter than 7.62x51 anyway.

A call to POF to confirm would set your mind at ease.

04-22-2012, 8:40 PM
I had planned on using .308 Federal Gold 168g ammo. I have put in an email to their tech support as this evening. I knew I could get excellent information on Calguns.

Thanks for the quick replies....

04-23-2012, 1:14 AM
Yeah, the lower's label means literally nothing at all.

04-23-2012, 7:42 AM
Lowers label doesn't mean anything the 762x51 on the barrel is just marketing so consider it a 308.

If you handload for it get full length small base dies and make your ammunition no longer than 2.8 COAL.

04-24-2012, 8:57 PM
As I knew it would be, you guys were right. I also talked to the guys at POF today and they confirmed that I would be able to shoot 7.52x51 and .308 (same stuff) without any problems at all.

I will give you a range report as soon as I can get some trigger time. The Geissele-SSA-E feels great so far!

Thanks again


04-26-2012, 1:32 AM
I have an ar10 with .308 lower and a 7.62 NATO barrel. If I shoot .308 win out of it, it will jam almost every time it's fired. The 7.62 NATO rounds will almost never jam. Shoot whatever your barrel is made to shoot.

04-26-2012, 5:28 AM
I will give you a range report as soon as I can get some trigger time. The Geissele-SSA-E feels great so far!

That's a sweat trigger at 1.2lb 2nd stage, breaks like a candy cane. I use their HS DMR, I like setting mine to 1lb or slightly less, breaks like an icicle. Can't go wrong with a Geissele.

04-26-2012, 5:50 AM
I have used 308/7.62 in my bolt actions as well as M1As for many years.My Aero/Armalite doesn't care either.If I had jamming problems,I would check the headspace.My friend shoots the Armalite T model upper and his research showed the Fed 168 gold as the go to round.Last time I was with him to shoot it,they did not seem to group well.He had some other brand that did extremely well.Point is you may have to fool around to find what is best in your gun.My Armalte carbine is fair with most bullets.Funny though,I load some 130gr varmint hollow points that are 1/2" at 100yds.Yes they are short.The gun likes 150gr Sierra Gamekings as well.

04-26-2012, 3:42 PM
Thanks for the info Coyotegunner. My SA M1A Scout likes the Federal 168 Gold Match and I was probably going to start with that to see if I can get inside the 3" groups ay 100yds, which I should be able to. I know they are 2 totally different animals. Ill give you guys a range report this weekend unless the wife puts the brakes on my trigger time.

Thanks again guys