I tried to get a 6BR to work with AW mags and the HRD kit and failed. I was able to get the 6BR to feed flawlessly (about 200 rounds so far without any issues) using the Primal Rights magazine kit and AICS 10 round mags.What magazines is everyone running on their BR variants? A few years ago I ran an AICS w/ Primal Rights BR Kit and it ran flawlessly in my Axiom. Planning on a 22BR Zeus.
Important note: the 6BR worked with long for caliber 107 Sierra bullets. When I tried to work up some rounds for varmints (6BR with 62 grain Barnes Varmint Grenades and a much shorter OAL) I ran into feeding issues as well. I am still trying to make this work but am starting to think that 6BR won't work with magazine feeding with short and light bullets.