Looks like count 4 in the indictment posted is pretty much a done deal. They actually have a youtube video showing a tripwire rigged explosive and it actually going off while wearing sidearms and carrying rifles. I had no idea that carrying a gun when doing that is a federal crime, but if so, the evidence for that count is actually on youtube. If these 4 charges stick, this group will be in prison for a long, long time.
I haven't seen the video, but there's a category of weapons classified as "destructive devices." That's not limited to full-auto. Class 3 licenses.
If I can get the time off, I'd like to court watch this if it goes to trial. The arraignment was in Detroit, about 40 minutes from me.