AR receiver wobble

[fastcarsgofast]

I did a budget build with a PSA kit and lower receiver. There seems to be an excessive amount of wobble between the upper and lower. The only way I can stop it is to place an o-ring on the front post. I know a little gap is to be expected but this seems to be on the far limit of spec. I want to replace the upper with a new stripped one and just move my barrel and parts over to it. I’m not sure what brand will mate with my PSA lower. Any suggestions are appreciated.

 

[cmshoot]

I did a budget build with a PSA kit and lower receiver. There seems to be an excessive amount of wobble between the upper and lower. The only way I can stop it is to place an o-ring on the front post. I know a little gap is to be expected but this seems to be on the far limit of spec. I want to replace the upper with a new stripped one and just move my barrel and parts over to it. I’m not sure what brand will mate with my PSA lower. Any suggestions are appreciated.

Any spec upper and lower are supposed to go together. As to how tight a fit you get, you’re going to have to try, as you don’t know where the issue is; in your upper or lower.

Is your upper undersized, or is your lower oversized? Could be that they are both within specs (albeit PSA’s “specs”) but the upper is at the bottom end of tolerances and the lower is at the upper end of tolerances. Add those together (referred to as stacking tolerances) and you could have an issue.

I get being bothered by your upper and lower figment, no one wants a rattly gun, but it shouldn’t cause any issues and has no bearing on accuracy.

 

[10-8 Gunworks]

Shove an accu wedge in there, or make your own from silicone. The plugs I use for cerakote work great.

 

[SirBannedAlot]

Accu-wedge. $5 fix. Pop it in, trim it to fit with an exacto knife and call it a day.

 

[FLcracker]

What they said...OR just put a dab of some hi temp auto gasket maker on the lower rear around the buffer tube interface, when you have the upper and lower separated. Just one small spot on each side. Let it dry and you have your accu-wedge with something you may already have in the garage. Will make having to probably use a punch and hammer to open the upper and lower though, as it will exert force on those two components. Stops the rattle.

 

[Kaotiktribe]

Accuwedge would definitely help, but this is why i stay away from "budget" builds......

 

[Hayata]

My M16A2 felt so loose you could almost slide a credit card between the upper and lower...

 

[cjnowell72]

If you were closer i would give you and accuwedge. Got a couple layin around

 

[jeep78]

These pins will take the slop out

 

[Paxdad]

Where does one get said pins??