Bolt Catch/Plunger Spring Issue

[BTL BRN]

This is new one for me. I noticed at the range today that the spring tension on my bolt catch was noticeably less than designed, and that the bolt catch itself was far too "wobbly." Figured no big deal, I will just remove the catch at home and replace either the plunger or the spring.

I pushed the roll pin far enough to remove the catch, and expected to have a plunger and spring lunge from the lower … no dice; in fact I cannot get them to come free from the lower.


I contacted BCM to see if they have any tricks to remove these … anyone here maybe dealt with this before?

To make things more "exciting" this is a registered SBR lower.


https://i.postimg.cc/3k7jC0kj/Bolt-Catch.jpg (https://postimg.cc/3k7jC0kj)


LOWER -
I have about 2500 rounds (ALL suppressed) through a FACTORY BCM lower (minus a Geissele trigger).

[1_click_off]

Just had a thread like this on here. Check it out.

https://www.m4carbine.net/showthread.php?224558-Stuck-dent-under-bolt-catch-remedies

[ssc]

Had the same issue on a new LMT complete lower. The recess was out of spec. Can't remember what the diameter is supposed to be, but gauge would only go in a 1/3 of the way. The recess was badly tapered. Start with using dental pics and try to get a bite and pull it out. Then there is the magnet trick followed by the vacuum trick. I always have spare parts, but if you don't use a screen. Then there is the drill trick and even a compressed air trick. There is the glue trick. Some are explained in the above link. Now before I begin a build on a stripped lower, I measure the recess prior to the build. It took me hours of using all the tricks to get it out. It was obvious that the LMT person who built it and signed off on the little card knew of the issue as you could see where he had tried to get it out and had scrapped off the black finish.

Cheers, Steve

[opngrnd]

It's possible the bolt catch took a hard enough hit in the correct manner that it "dinged" the receiver, peening the edge of a hole in a way that doesn't let the detent move freely. I had this issue once, and S&W cleaned up the hole and sent it back. I no longer own that rifle, but the current owner isn't having issues with it.

[BTL BRN]

Just had a thread like this on here. Check it out.

https://www.m4carbine.net/showthread.php?224558-Stuck-dent-under-bolt-catch-remedies

Greatly appreciated - as are the other replies in the thread! I was able to remove whatever "burr" it was with a 1/8" drill bit; just slowly, easing the bit in the plunger/spring hole.

Actually re-used everything, we'll see if anything needs swapping.