FYI, in support of a friend and former XJT pilot (current CAL pilot), if anyone needs machining services or a suppressor, check out
Untitled Page. Dave is his name and is VERY knowledgable about firearms. He does all the machining himself and hand makes the suppressors. The website isn't much, but if you need anything, call or drop him an email and he'll talk your ear off.
Several years ago, he took me out to a friends place to shoot - I had never fired a weapon before. My first was an his M203 grenade launcher mounted on an AR. It was just a practice round but it was cool anyway.
Check it out.