[MaybeStopCalling]

I fixed my bolt catch by shimming the catch using an AEG shim, and gluing part of a plastic card to the bottom of the catch where the magazine contacts the catch. It's been a perpetual issue with WEs. Also replaced the bolt catch spring with a BIC pencil spring that I trimmed down, and everything (particularly the shim) got a coat of white lithium grease.

It took 200 rounds before my M4 loosened enough so that the magazine seated easily. I still tap the bottom to make sure its locked though, dropping one on my bare foot is one mistake I refuse to ever make again.