Peiper wrote:i don't think so because my ww2 unit buys mg43s and then convert them, and they tell everyone about it.
I'm sorry to say that most likely this is not legal.
If your unit has a type 7 or type 10 FFL, performs the conversion themselves, and registers the "new" full-auto MG34, then your unit can own and possess it. But even with this license, it is still illegal to transfer the converted MG34 to a civilian -- for example, yourself or any of the other individual members of your unit -- unless it was converted and registered before May 19th, 1986. Any guns converted and registered after May 19th, 1986 can only be transferred to another entity with the proper type of FFL.
But from what you are saying, it sounds like your unit buys MG34's previously converted to semi-automatic only, and firing from a closed bolt. Next, they have someone "undo" the semi-auto conversion to return it to its original condition (fully automatic, firing from an open bolt) for a fee. Then, your unit takes possession of the full-auto MG34.
This is definitely illegal because (as I explained earlier) converting it back to full-auto makes it a "new" machine gun to the BATFE.
This issue is something that you really need to bring up with your unit. The illegal manufacture or transfer of a full-auto firearm is a serious felony, punishable by a $250,000 fine and a 10-year sentence in federal prison.