barrel ends about 1" from end of handguard/rail. Flash hider is about 1.75-2" long. .5" is on the threads of barrel and about .5 - .75" sticks out the end past the handguard. a 9" barrel would be just about flush with the end (end of barrel threads flush with end of handguard).
flash hider is the gemtech HVT quickmount. It came with the suppressor, and is the one pictured here standing on end at the top of the pagehttp://www.gem-tech.com/store/pc/7-62MM ... 15p120.htm
I specifically wanted the can to be inside just a bit. The BAR rail is large in diameter to allow for it and the way the quickmount works makes it possible. Not release buttons or levers to release the can. Just push in and twist 90 degrees to lock/unlock.
When I fire it without the can, the muzzle blast doesn't effect the rail as much as I thought. No burns or powder residue at all, as most of the blast goes forward and not out to the side.