AR-15 BS Thread

That's the first I've heard of that. I've owned many many variants of ARs over the years and shot with friends that have ARs, and have never seen pins walk out. I've never owned a PSA lower either though. I currently have an Anderson, Ruger and Larue lowers and they have all been great with the MBT triggers dropped in em.

 

This is correct as the barrel needs to seat before final torque

 

Out of stock everywhere.

I may just swap my anti-walk pins over to the good gun and use the LaRue pins on the old one. Nothing magical about all the other small parts, although I'd like an ambidextrous safety. Some kits come with the anti-walk pins, but man, some are like 80 bucks! Crazy times, but I am in no hurry, just fidgety.

 

I built another psa gun for a friend for his bday and the pins in it where fine. Sometimes you just get one that the quality control officer was hungover that morning haha. This was a factory built lower btw.
Non of the other many lowers of various brands have this issue

 

I do have a PSA upper on my wife's Anderson lower. That gun shoots sub MOA surpisingly.

 

ive always done 50 as a middle ground, but it all depends - some require proper timing to install the handguard

even radian stated 50 in their handbook

 

Please sir my poor eyes are blinded

 

My wife’s SPR pins used to walk out. I think it was more of the cmmg problem though because it doesn’t walk out after I threw a Triggertech in.

 

Like many manufacturers, PSA outsources the machining of a lot of their parts. In terms of sticking to tolerances however, they are the least demanding of the manufacturers that I've seen. Barret goes way over the top, and rejects parts for the slightest reason. There is a box of Barret lowers and handguards sitting in the vault at work with tiny blems that PSA wouldn't even glance at... There are a few dimensions on Barret handguards that must be within +/- 0.0003", while pretty much everything on a PSA handguard is within +/- 0.003-0.005" though I've seen some go at +/- 0.010" over nominal.

 

So I’ve been wanting a 12.5… now I’m thinking I might as well find someone to pin and weld a 13.7 for me and miss all the paperwork that goes with a 12.5 lol

 

My thoughts exactly

 

Most factory blowback guns use buffers that don't weigh nearly enough. This will beat the hell out of the FCG, among other things Try a heavier buffer and the pins won't move as much because the bolt isn't getting violently slammed back and forth.

I have 10oz buffers in all my 9mm blowbacks.

 

There is a spikes 9mm buffer in there now. it's heavier and longer.

 

Nah. Even their "heavy" version is only 7 oz.

https://www.kawvalleyprecision.com/KVP-10oz-Tungsten-Blowback-Buffer-p/kvp-10oz.htm

I use these KAK weights as well.

https://www.kakindustry.com/9mm-carrier-weight-extra-heavy

 

I am a happy camper with my 8.5oz from
https://heavybuffers.com/uciw9.html
(Please note, they make buffers for specific tube/stock applications)

 

The spikes is 7.7oz and the 9mm Kaw Valley buffer is 7.5oz. The 10oz one is for suppressor use I thought.

 

The gun will work with lighter buffers. Mfgs use them because they're cheaper and most people don't really know when their gun is getting beat to shit. But bolt velocity is way too high and port noise is much worse when there's too little weight. The potential for out of battery ignition is also higher. I learned most of this trying to get my 10mm AR working. I went back and revisited all of my other blowbacks; 9, 40, 45 and was shocked how much better they run with more weight.

It's not just guesswork either, there's some real physics and math behind it. Every blowback gun I have pretty matches this website

https://10mmautocombat.wordpress.com/blowback-bolt-calculations/

My 10mm AR buffer is 2.1lb.

 

2.1lb holy.... Thanks for the knowledge. I'll try out the KVP 10oz
Thanks

 

GOA's link for commenting on ATFs proposed pistol brace ban...refresh the page to get slightly different messages and subject lines, or write your own.

https://www.gunowners.org/na06102021/

 

AR pistols have dropped as much as $200 around here and some of the emails I am getting about the same