This is a Public Service Announcement for anyone still running antiques:

A SilencerCo Trifecta muzzle device won't fit through a DD Lite rail. The opening at the barrel nut end is about a 1/16" too small.

One of my weekend projects was to stick a mount on my ol' BCM...Got the rail off, chucked the barrel in the vice, twisted off the A2, got the brake shimmed (not a fan of brakes, but it's what I had in the parts box), Rocksett and torqued to 15 ft-lbs...All good. Then I go to slide the rail back over and bam! No go. Shitballs.

With the rail re-mounted, there's not enough barrel sticking out for the vice blocks to grab on tight enough to keep things from spinning, so I ended up just saying quick prayers to Fat Buddha, Baby Jesus, and the Flying Spaghetti Monster and torqueing that mother on using a BEV. Everything's still straight, so I guess it worked out, but getting it back off in the future may be an adventure.

Anyway, if you're still running a DD Lite, and you want to mount a Trifecta, save yourself a half-hour and don't bother dismounting the rail.