Answering posts like this open up a lot of opportunity to start insulting other people's capabilities. I don't know any of your friends, they may be supremely qualified. I'm not speaking to them specifically. As a general statement, I will say that gunsmiths are kind of like mechanics. I know some great A&Ps that can keep a jet running top notch and I know some car mechanics that can help squeeze every mile out of your car. Both are mechanics, I would not want one to do the other's job. Something about lanes and stuff. A smith can have decades of experience but it might not be relevant to putting ARs together. And as far as armorer courses, depending on who they took their class from, there might be a fundamental design and function theory missing. It's one thing to replace one factory part with another factory part. It's another thing to take a DD 300 blackout barrel with an LMT bolt, JP adjustable gas block, and BCM receiver extension set and put those together in an Aero receiver set and have them match up and work "flawlessly"(oddly specific, yes). Getting a rifle from someone who puts them together everyday for a living is different than even getting it from someone who professional works on guns in general. I've had the good fortune to have a lot of great discussions with some of the guys from JP, and there is a lot different about a gun put together by someone that is doing it for the 1000th time. They aren't worried about what part is torqued to what, that's a part of the macros of the process, they're focused on the feel of how the small parts drop in and interface with each other. Science to art and what not.
