Finally got to the range with my CAR A4. It has a RRA upper, RRA 5.56 lower with 6-position stock, RRA mag block, RRA 9mm hammer, RRA 9mm buffer, and RRA converted Uzi mags. The first several mags fed and fired without any problems. Then I started to get failures to eject. It was just starting to get dark outside so I packed up and went home. I checked out the rifle when I got home and noticed that the mag block had shifted down slightly in the magwell and the tension screw was a little loose. SO, my question is...How tight should I make this screw? I don't want it to come loose again but I don't want to damage anything either. Is it possible to damage the magwell by over tightening this screw? I didn't use loctite or anything on it when I first installed it because I didn't know if it would need to be adjusted after test firing or not. Should I use loctite(blue of course) on the tension screw?

Thanks in advance.

I have a factory built RRA 9mm and the block in it is rock solid.  I am not sure if they used loctite or not.  However, if I were you I would ask the question in the industry forum under RR's board.  The moderator there answers questions pretty quickly.  That would probably be your best bet.  Sorry I couldn't be of anymore help...good luck!

I have the RRA 9mm setup.  I did retighten the block in mine after shooting the first couple of mags.  It had become a little loose but did not cause any functioning issuses.  I don't have a torque value  but it is tight.
If you read this board alot..... you will know to keep a eye on the pin that holds in the extractor on the bolt!

Forgot to mention that I did not use Loctite.

I have nearly the exact same setup as you (except it's a Bushmaster lower), and I exprerienced a few FTFeed issues. I think it was because the magwell was coming loose after pulling a few mags out. I didn't even tighten the screw when I first got it, but I'm going to now and see if that makes a difference next time.

The extractor pin looks fine. (for now) I think the block shifted down just enough to make the ejector miss the cases. I'll have to wait until I can test it again.