Hey all. Has anyone used these on any of their AR builds (thouroughbred was selling them a while back)? I have a chance to pick one up for a URG-I clone. I really like them for the cool factor, but they look beat to holy hell. Wondering if it might be better to just use a new Colt upper instead. I plan on putting a lot of rounds through this new clone build, so I was curious as to if anyone has had any problems with them. Haven’t really ever heard of military uppers failing, but the fact that they seem like takeoffs already makes me a bit nervous. Link below shows something similar to what I have a chance to buy. Thanks for reading. I appreciate it!

https://www.thoroughbredarmco.com/product/539/

Salty with a Colt amount of wobble but all my surplus uppers have been fine just...special

Haha, I’m perfectly fine with salty and special. If I go with the surplus FN upper, it’ll be the only used part on the entire gun. I just don’t want it the to crap out on me a few thousand rounds in.

What exactly do you anticipate "crapping out"?

I’m mostly concerned with the surplus upper receiver. This is my first AR build. I’m more experienced with AKs (apologies lol). I read somewhere that after a ton of rounds a heavily used upper receiver might start to become out of spec in certain areas (charging handle issues, potential cracking). Could be completely wrong. From the research I’ve done, issues with the upper receiver itself seem very rare. I just wanted to get some feedback before I put the gun together.

Upper receivers typically last north of 200K rounds issue free, whereas the AK receivers tend to crack at about half that round count.

Lugs will wear causing some play/slop over time.

I wouldn't sweat it personally.

A non-issue

I really appreciate all the input, everyone. This was all super helpful. I went ahead and got the FN surplus upper receiver given all the input here. Thanks for your help! I think it’s going to look great once the rifle is all together!

I have a different FN surplus upper from Thoroughbred and I haven't had any issues with it. It has very noticeable wear and is wobbly, but my lower has a tension adjustment screw so that tightens things up. Overall, I'm happy with it.

I service them for Uncle and haven't noticed any issues.

I have a CQBR BII gun employing one of those beat FN uppers and it's one of my most accurate clone guns.  Does this have anything to do with the upper?  It's a near certainty that it does not, but the upper works fine.

I got one of these from Thoroughbred a few years ago for 90 bucks and built a basic bitch Block 1 out of it. I stuck one of the CDNN closeout 99 dollar Remington Defense SOCOM barrels in it. 58 dollar AO mil contract BCG, 3 dollar milsurp charging handle, RTB Colt overrun buffer system, early B5 milsurp stock, Schmid Tool GI Nuts LPK and FN M4 marked lower. I think I've got 800 bucks into the rifle before accessories. I still need a sling setup and salty ACOG.

The upper was definitely usable. It wasn't so egged out that an ejection port cover wouldn't shut. The upper to lower fit wasn't tight but within the realm of acceptable.

Once I find an ACOG I'm going to give it the ol' GWOT Rapco/Aervoe rattlecan treatment, so the threadbare anno won't matter.

Who wants a perfect safe queen finish on a clone?

Certainly not me. I've got OLD surplus C AF, C Cardinal, all the Diemaco flat tops and a Diemaco C7, an OG Colt XM4 upper... I have numerous salty surplus receivers. This was one of the few from the beginning I'd planned for spraypaint.