Bolt catching on bolt catch .

[Klem]

big,

Someone made a mistake at the warehouse - wrong spring, wrong package.

[Lastrites]

I have never seen a spec for the space between the mag catch and bolt face when the BCG is in full cycle all the way back, but there should be at least .120-.125 minimum space or better in my experience.. Out of spec buffer tubes, poor installation, weak or using the wrong recoil spring will show after doing this test common test..

Bolt face on most ar's are supposed to 1/8" to 1/4" in front of the back edge of the ejection port, if it disappears beyond the back of the port all sorts of wonky malfunctions may occur. On 9mm uppers the bolt face is supposed to stop a 1/4" past the bolt catch.

[montana]

Bolt face on most ar's are supposed to 1/8" to 1/4" in front of the back edge of the ejection port, if it disappears beyond the back of the port all sorts of wonky malfunctions may occur. On 9mm uppers the bolt face is supposed to stop a 1/4" past the bolt catch.

Thanks for the info, I have never seen an official spec for this measurement. If there is one out there, I would love to see it. SureFire,"designed by Jim Sullivan himself" Optimized Bolt Carrier Group, cut the gas key on their BCG, shortened the buffer and elongated the cam groove.. This allows more recoil travel and dwell time, creating more energy to strip the round from the magazine.. https://www.youtube.com/watch?v=BBVtx8zUcF8

[bigdaddyjak]

Thanks for the info !!