On the BCG theres the pin that ci trols the camming action of the bolt in the carrier, the firing pin goes through this pin too. I'm not sure the technical name for the piece but theres a recess in the upper reciever (on the outside it's the square bit on the left side towards the front) that allow that pin to turn, Cringesader in their infinite wisdom (or lack thereof) changed the geometry of the recess which allows the pin to begin rotation prematurely resulting in a complete lock up.
The BCG isnt the issue inherently it's the upper reciever. If you have the ability to compaire a normal AR-15 upper to a cringesader upper inspecting the cam pin notch. Theres been a few cases of premature rotation but for the most part they work quite well
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u/[deleted] Jul 03 '26
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