I jumped on a PSA 10.5" pistol complete upper a couple weeks ago for $259. I bought an Anderson lower specifically for a pistol build and put a KAK tube and Shockwave brace on it. All the rest is PSA parts.





I finally got to put it together last night and shot it today. It functioned flawlessly on the first 80 plus rounds of xm193 during sight in. I switched to Tula and got a stuck case on the 2nd round. I was able to lock the bolt back and mortar it to pop the case out. It did it 4 times total.

I switched back to xm193 and it ran fine again. After that the Tula started running fine.

I'm really not sure what the malfunction was. I got two split cases out of about 70 rounds of Tula. All the cases were in good shape with no deformities.



Zero case deformities on the xm193. Zero signs of over pressure with only slightly flattened primers. Necks and shoulders in good condition.  

The accuracy was nothing to write home about but I was having a hard time seeing the outlines of the white painted steel targets in the bright sun. Once clouds moved in I could keep my shots inside a 3x3 silhouette target head. I am sure I'll get better results if i play with the ammo choice.

If I was going to guess, I would think the buffer is too light.
The brass can stretch but not the steel.

So the high pressure causes a split case on the less forgiving steel.
A heaver buffer will let the pressure ease and slow the bolt carrier's movement.

Every PSA I've ever owned sticks steel case like that until the chamber is worn in.

Has happened on nicer rifles too. Have had it happen with Hornady steel case even,  why I won't consider steel for defensive use IME a stuck steel case often locks the gun up tight.  My extractor usually rips the case head off when mortaring, as well.

Maybe a lower port pressure, i.e. a heavier buffer will help?

True but I always start new builds with H or H2 and BCM extractor kits so shouldn't be quite that bad. Seems to go away as the chamber wears in.

The last 40 rounds were fine. I'll just have to keep shooting it until I'm convinced it's fine.

One of my 16" PSA builds had a single stuck steel case. It ruined the outting because I had no way to punch it out. I carry a cleaning rod in my truck now.

The stuck cases today came out fine.

Same. Ruins the whole trip with no rod. I still don't carry a rod I just shoot brass ammo now.

I just built basically the same gun you did.  Same 10.5 inch PSA upper except with keymod handguard, PSA bcg, and an Anderson lower.  KAK buffer tube and blade.  

I run a H3 buffer and Wolff XP spring.  I also run a Sprinco 5 coil HD extractor spring with insert and no o-ring.  I consider the HD extractor spring a must on any short barrel carbine/pistol gas AR.

My gun functions perfectly with 223/5.56 ammo.  I usually use crappy steel Tulammo as a test ammo in a new buy or build.   I ran a box of 20 through this build and they fired and ejected fine except bolt would not always lock back on last shot.  

I always scrub the barrel and chamber on any new gun or build, may or may not help, just something I do.

I ordered the M lok Magpul AFG for It this morning. I think it's going to work out really nicely. It will help with indexing closer the the end of the handguard. I hope to get our and shoot it this weekend. I want to confirm 200 yard zero and get some more rounds through it.

Haha great minds? PSA lower, shockwave, complete PSA 10.5 mlok upper.

I run a H3 and springco blue spring, have had zero issues. But I shoot mainly PMC/Wolf brass.


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What do I need to know about running a light weight BCG in this pistol? I would love to drop another 3 oz with one of the AIM Surplus light weight BCG but does it require a heavier buffer? I am hovering around 5 lb 5 oz. The AFG weighs very little.