Hey everyone, I am in the process of building an M4 J9 pistol, now the front of the J9 is threaded, so a trick is to warm up the end of the pipe with a heat gun, and it becomes really malleable, so I then just slipped it over the end and put a screwclamp on the section where the threads are and tightened it up, since the PVC is soft it moulded the threads from the M4 into the tubing. Also PVC pipe with a couple of end caps make wonderful holders for the thin style tunigy batteries. It needs some sanding and customising to make it look more unrecognisable and I will drill holes the length of the main tube to make it look like a chunky suppressor. Its a build in process but I am happy with the concept so far.
Now I know I may be late to the party with these idea’s, but just in case I thought I would share.