RRA lower with M1S upper.  Have put about 300 rds Wolf 55gr through and I have now noticed that the bolt does not lock back on an empty chamber with the mag in it.   I have also noticed excessive wear on the bolt catch such that the sharp flat face is being worn down to an angle.  Goes bang every time with no ejection problems.  I do notice that the bolt catch is fairly tight but you can move it freely back and forth.  It did lock back when I first got it.  Any suggestions for why this is happening would be appreciated.  Thanks.

Will it manually lock back on an empty mag if you pull the charging handle fully to the rear?

If it does not, then you have problems with the bolt catch itself. If it does, then the rifle is short stroking.

Going back and doing it repeatedly I have noticed that if I do it slowly it sometimes stays back.  If done quickly it slides forward everytime.  It seems like that wear on the top of the bolt catch is the main problem.  Now the question is why should I have so much wear in the bolt catch after so few rounds?  By the way thanks for the quick reply.

I've never heard of one wearing down like that. I'd say that either you've got sharp edges (burrs) somewhere wearing it down, or it's just too soft to begin with. Replace it and you should be fine if you've taken care of any rough edges.

1. Remove the bolt catch pin with a punch. Place tape on the lower receiver on either side to avoid scratches.

2. Remove the worn bolt catch, spring, and plunger.

3. To install: drive the roll pin about halfway into the rear "hump".

4. Install the spring and plunger into the hole, then install the bolt catch in place.

5. Use a  punch inserted into the front "hump" as a slave pin to hold everything in place, and drive the roll pin in with a roll pin punch.

Doesn't seem to be any rough edges.  I'll take your advice and put in a new bolt catch.  Once it's done I will post the results.

Make sure the buttstock screw is not too far in. If it is, the buffer may be bouncing off it. This will do two things:

Bounce the BCG past the bolt catch and put excessive pressure on the bolt catch when it does work.

You said it used to work OK, but now is tight. If hammered too much, it could be bent or its milled recess may be damaged.

Is this a factory assembled RRA lower or a bare RRA lower with a Model 1 LPK ?  I got 2 Model 1 bolt catches that were out of spec.  The pivot hole had a step in it and would have been too tight.

rj

This is a gun show purchase that is a M1S kit on a RRA stripped lower.  The guy told me it was all RRA when he sold it to me (my fault for being stupid).  Of course this is before I learned how to build one myself.  I just ordered 2 new bolt catches from Del-ton that I will use to switch out the old one.  If it still causes a problem I will start looking for other solutions.  I'm hoping this is just a case of a bad part.

Just put 100 rounds through the rifle after installing the new bolt catch.  No unusual wear marks and it's working fine so far.  By the way, when I swapped out the old M1S bolt catch I took my punch and scraped the surface.  The metal was very soft and I could do significant damage with the punch.  I tried the same thing with the Del-Ton bolt catch and couldn't make a scratch.  I think this was all related to the metal being too soft.  Problem solved...I hope!