From my understanding there is a spacer built into the back of the tube to create a chamber behind the muzzle. Looks like cups only go so far down the tube and hit a stop. I may be wrong on that though. Never used this.
No I haven't. Unfortunately I live in a state that I can't own one. Do some research on form 1 suppressor. Tons of info and a friend of mine just moved to Montana and filed for his form 1 and was good to go in 30 days
The pri mk12 are awesome!!! I finally got to take mine out last week and start getting dope dialed in. Complete pri upper, and clone lower. Group is at 656 yards with 8 mph wind. Gun is a lot of fun to shoot
Just a heads up, if you have access to a 3d printer there is a file on thingiverse for a dillon powder die. Might solve your shipping problem to the land down under.