I'm talking about before you modify the firing pin to float. In the scenario I'm talking about, someone has done their mods required to start welding the receiver (blocking lug, widening grip slot, grinding off sear lug on bolt). Then has successfully welded up and cleaned up the receiver to operate. At that point, before any more work is done to the bolt (and in this scenario the grip pack is irrelevant, semi or full) wouldn't it theoretically be simple to make it fire indefinitely? Just assemble everything except the grip pack, somehow hold the bolt back, put a loaded belt in, and release the bolt.
All this dawned on me after I finished welding up my receiver (with proper mods, mind you) and was using the bolt assembly to put in the rails. I guess what I really want to know is if I should get something modified TONIGHT to alleviate this engineering problem I'm seeing, or if I'm just crazy (and of course crazy is always on the table