Barrel Extension Separation!

[grayfox]

In this case, the barrel index pin was neither sheared nor came loose. It remained intact on the barrel extension throughout. Separation occurred regardless of the barrel index pin. I do recall that the vendor lost their chief machinist at about the time of my purchase and that those left behind had to quickly learn to the machines to keep up with demand. I also thought to re-visit a bookmark on my computer from a Shooting Illustrated article (12/2017) about nitride barrel finishes; excerpt:
"... the nitriding process tends to loosen up barrel extensions. So, existing AR-type barrels that are treated must have their extensions properly timed and torqued afterward."
https://www.shootingillustrated.com/arti...-finishes/

The real point being made here is that the proper technique is to nitride the barrel first, then install, torque and time the extension/alignment pin, afterwards. Since the barrel and the extension are usually 2 separate alloys, their heating/cooling coefficients will differ and the nitriding process will cause them to loosen at times. So this guru-shop must not be as guru-good as supposed. I would strongly consider shopping elsewhere.