Bolt locking to the rear question

[ODA CDR (RET)]

I recently purchased a Rock River Elite Operator 2 AR-15. I took it to the range to zero and afterward did some range fire. After the third 30 round magazine, the bolt would sometimes lock to the rear as if it were an empty magazine (not empty though). This would happen three to four times with the next two 30 round magazines. I used the new RRA magazine and a new Magpul magazine, with the same results. The ammo is Federal 62 gr 5.56. In 30 years of firing M16 and M4's, I have never had this occur. I checked to make sure the bolt gas rings were not lined up and other than that, no mechanical evidence of something wrong. What could be causing this to happen and how can I correct it. Thanks

[chance]

Do you have anything attached to the bolt release? For example a MAGPUL BAD? If so it maybe holding the bolt release up. Also without a mag in it does the bolt release spring back after you press it down? If not it maybe bouncing up during firing and grabbing the bolt.

[ODA CDR (RET)]

Nothing attached to the bolt release, and spring is strong. ?????

[koz]

Sounds like a bolt catch problem. When it locks back, is the catch engaged? It may be the catch wasn't machined (or cast) properly and the round is pushing it up.

Other thoughts - where do you hold the rifle with your weak (left) hand? Could there be any chance that your hand is hitting the catch?

Where did you buy it? If directly from RRA - I'd call as ask for a new bolt catch.

[ODA CDR (RET)]

I have an email into RRA, since their phone stays busy. I have a feeling it's the bolt catch, I just can't imagine how its activating only sometimes by it self. Nothing is near the button while I'm firing.

[35NCO]

Hmm. That's an interesting problem. It would not be the spring because the spring uses the tension in the other direction, to hold the bolt catch down. Unless it is somehow inconsistent with tension. As mentioned above it is possible that the catch is too big. With everyone and their brothers making AR parts right now and trading between each other for the cheapest contracts, there is a lot of garbage about.

Another issue could be the lower being out of spec. From experience, I have a rock river lower that the slot for the catch is very narrow. I had to shave the shelf of the catch to make it fit. That lower is pretty old, but who knows, could still be happening there. When you break the action, is the catch sitting flat on the lower? Is it really easy to pull it up? Does it get caught and bind?

It is pretty easy to replace if you have a small long punch and plastic tip hammer, or you could have a local gunsmith do it. It really should not take anymore than 5 minutes.

Interested to hear what it turns out to be.