Happened across this on TFB, thought it was somewhat interesting. I’m gonna stick with properly ported barrels and BRT’s gas tubes, but I’m curious what M4C thinks.

Product page:
https://www.riflespeed.com/RIFLESPEE...rols_p_12.html
TFB article:
https://www.thefirearmblog.com/blog/...-gas-controls/