I have one of the Bulgarian 4-piece attatchments that I just got. I placed it onto my sight base and tightened it. It locked at the first slot, but I found that it could turn and lock at the second one halfway oon the other side, so the threads were still going. It is easier to do the first slot, but would gases from firing be a problem? Would there be a gap inside? Does it need to be tightened as far as possible?
Thanks! Hope this makes sense......

I'm not sure if it's a gas booster, but it's the flash hider that is made up of four parts that can be disassembled. It's not the cone style, and is the newer design of the two.