I have mounted two Vortex Crossfire scopes on a 300 Blackout rifle. The mount is a Brownell's one piece Ar mount. Both scopes the reticle either rotated in circles or become misaligned after 50 rds. One scope was a 3X9 and now a 4X12 has failed. Is Vortex Crossfire junk or maybe the mount. Vortex won't send me free shipping labels anymore unless it's a brand new sale.