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Discussion Starter · #1 ·
I bought a USC/UMP conversion done by TE and the seller also sent me the left over parts from the conversion including the UMP fire control parts. I just want to make sure that I am not in possession of anything illegal here. One of the pieces included looks a lot like the friction sears used in the HK9x series, but it is made of plastic. Is that the "auto sear" part of the UMP? If it is, am I in any violoation of NFA rules? Are any of these parts contraband. I am not that familiar with the usc ump parts yet so I just want to make sure.
 

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No, you're ok. Similar to how it's ok to own factory MG packs as long as they aren't modified to fit a semi-auto HK94 receiver, as long as you don't modify your USC receiver to accept the lower with the MG parts installed in it, you are ok.

The UMP lower will not fit correctly onto a USC receiver without modifying the receiver. Besides that, more likely than not, TE also filled the section of the lower where the full-auto parts go with epoxy or some other plastic so they couldn't be installed into that lower anyways.

On the USCs, there is a lot more that needs to change to make one fire in full auto than just a trigger pack and lower like on an MP5. The UMP bolt won't fit into the USC receiver without modifying the receiver and maybe the UMP bolt as well. The UMP lower with the f/a parts installed also won't fit without an additional modification to the receiver.

It wouldn't be hard to do, but there are more steps than just swapping carriers and clipping and pinning a pack like on an MP5.
 

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Discussion Starter · #3 ·
Thanks A-Dave. I knew there had to be more to it than a simple swap, the dems would never allow something that easy to make f/a in our hands (lol, can you say ar15).

Thanks again.

sniper1
 
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