For calibers that use a gas tube we consulted a spring engineer to create a self-locking
retaining ring for the lock collar to keep it close to the barrel extension when removing the
barrel assembly from your upper. There are limits on the diameter of the barrel profile, but
we believe this will cover the majority of barrel diameters that are common in AR15s. Our
barrel stop (SKU: BSU) will continue to be available for blowback pistol calibers to provide an
index pin since a gas tube isn’t present.
The retaining ring will be installed during the barrel install step on the instructions,
after the lock collar, and prior to the gas assembly.
You can use two screwdrivers, or a section of pipe with a 1
inch inner diameter to press the retainer down. After
sliding the lock collar over your barrel, stand the barrel
vertically on the barrel extension. Orient the ring with the
tabs angled towards the muzzle and slide it over the barrel.
Press the ring down until it contacts the inside of the lock
collar. Continue with the installation instructions as
normal.