[ssrc30]

I got my M4 from Velocity, after waiting 2 months for parts to replace a leaky magazine, I finally ordered the Madbull valves from airsoftparts.ca.

I got the gun working again, but the problem is it doesn't cycle properly. It shoots, but the bolt locks in the far back position after every shot. It does this in semi and full auto, also with the magazine lock switch both turned on and off. I have disassembled the gun and nothing seems to be out of the ordinary, no broken or obviously worn parts are visible.

Any ideas what might be going on here?

I must also say that in order to keep the gun firing without the bolt locking, I have to hold the bolt catch down.