Sent you an email.

Did you get a chance to shoot yours?

I’m waiting for a gas tube

No, I went shooting on Sunday but didn't bring the 308 with.

So this is kind of interesting. I went shooting on Sunday and didnt bring my new 308 because my buddy said the 224 Valkyrie upper I built for him was having all sorts of feeding and extraction issues and I wanted to get that running for him (I cleaned the chamber and lubed the BCG and it ran perfect ).

One of the other guns my friend brought was his somewhat new 18" PSA PA10 308. We put about 120 rounds of factory fresh Federal 308 ammo through it, on top of the 40 he shot in that gun previously. It ran nearly perfect with surprisingly decent accuracy. The only malfunctions were a spent case not being ejected quick enough before the next round tried to feed, that happened twice. I didn't notice any over pressure signs or blown primers in the spent brass, although I didn't check every single case either.

When we left he asked if I would store the rifles he brought until he and his family closed on their new house and settled in. No problem. Once I was home I took both mine and his ARs apart to clean and decided to check the headspace of his PA10 as well as my 308 with his bolt. His PSA BCG is nearly identical to my Toolcraft BCG. The only difference between the bolts and carriers is mine (Toolcraft) has a O-ring extractor and his (unbranded PSA) doesn't.

Using his bolt in my gun I could get it to close more than my bolt on the GO guage but still not fully. Then, I checked the headspace of his factory assembled PA10 upper with both his bolt and mine. Both failed to close on the GO guage. I'm not exactly sure what to take away from this but his PA10 now has nearly 200 rounds of 308 through it and it failed a 1.630 GO guage. I'm going to shoot mine the next time we hit the range.

Huh

I’m following as I’m in the same boat

So those were 308 guages. What brand?

I also got another bcg from brownells(supposedly toolcraft/Aero , as they look identical) and the newer bolt is even tighter in my Rainier barrel, but chambers a 308 round like butter and not fully on a 762 rd. Mine is also all apart.

They are Clymer gauges from Brownells.

Clymer .308 Win Gauges

The Go closed on all but one of my AR10s and the one that it wouldn't was a custom Lilja barrel with a chamber set to keep 175 GMM .030 off the lands.  As I recall some were kind of snug.  I cleaned them off but wipe them down with an oily towel and try it again.  That's what I did.

I made a thread about my barrel in the Rainier Arms subforum and the only response I got from them was that they use PTG guages. I'm definitely not buying guages that are $60 a piece. They never responded to the email I sent over a week ago either.

@mustangfreek

Do you have the same barrel I do, a Rainier Arms Match 308 Intermediate Lightweight?

No

Older gen 1 ultramatch

So did you fire this thing yet?

I have a similar setup to yours if I remember right ..well I got mine together minus the scope and had to ace it up and see what it would do Aero m5,Armalite 308 buffer kit (A5 length, with H3 buffer), rainier gen 1- 18” - Int. Length gas w/.082 port (which seems on the small side, but it’s their match/hybrid chamber.

With the h3 it ran fine with federal 308-165gr Nosler and LC 147 xm80, both locked back, ejected and 3:30 ish ejection.

So tried some wolf, no go. Would fire and spit out a case about a foot and not lock bolt back..

...so went back up with a h2 and it now fired and ejected the wolf ammo , and ran fine. Brass to about 4-5 o’clock. But it made the 308 ammo way more recoil. Brass to about 1 o’clock. So it seems gassy with the h2.

Gonna just run the H3 for a while with some good ammo and let it break in , so to speak.. then maybe try the wolf again..

No rounds through it yet. Maybe this week if I get a rain day at work.