I'm considering picking up an HK USC 45 in the near future.  In stock form, it doesn't really do a whole lot for me, but the UMP conversion is enticing.  I don't think it's a very practical purchase, but I like the uniqueness and I've wanted to add a pistol caliber carbine to my collection.

 

Anyway, my question is if anyone here owns a UMP conversion and if so, where did you have the conversion and compliance work done?  I'd rather give a local gunsmith the business if they're experienced with the conversion, rather than send it across the country.  I'd need to have the USC receiver milled out a bit to accept UMP magazines, the UMP stock pinned, and magazines blocked, while maintaining 922r compliance.  I'm hoping someone in NJ is familiar with and willing to handle the work.

I owned a USC that was modded to take grease gun mags.  Not a UMP conversion per se but same basic principal. The way mine was done was the upper receiver was milled like you said, but it had a completely separate lower for the grease gun mags.  

 

My advice to you is to shoot one before you buy it (if you haven't already).  I bought mine without ever having shot one before, and I wound up being underwhelmed by it.  It was reliable and accurate, but was very bulky, heavy for a plastic gun, and the recoil was pretty bad.  I ended up selling it and plan on getting an mp5 clone in 9mm at some point.  I have shot those and had much more fun with them.  

 

Other pistol caliber carbines I either own or have shot and liked better are the KelTec Sub2000, Taurus GT2, Marlin Camp carbine, and a dedicated 9mm ar.  

I owned a USC that was modded to take grease gun mags. Not a UMP conversion per se but same basic principal. The way mine was done was the upper receiver was milled like you said, but it had a completely separate lower for the grease gun mags.

 

My advice to you is to shoot one before you buy it (if you haven't already). I bought mine without ever having shot one before, and I wound up being underwhelmed by it. It was reliable and accurate, but was very bulky, heavy for a plastic gun, and the recoil was pretty bad. I ended up selling it and plan on getting an mp5 clone in 9mm at some point. I have shot those and had much more fun with them.

 

Other pistol caliber carbines I either own or have shot and liked better are the KelTec Sub2000, Taurus GT2, Marlin Camp carbine, and a dedicated 9mm ar.

How much does the mp5 clone go for?

How much does the mp5 clone go for?

There are a bunch of companies that make them. $1k on the low side 2500-3k for the best ones. There was a slickguns deal for one of the better quality ones a few months ago for $1300 that I am still sore I missed out on.

There are a bunch of companies that make them. $1k on the low side 2500-3k for the best ones. There was a slickguns deal for one of the better quality ones a few months ago for $1300 that I am still sore I missed out on.

Whoa. I'll pass. Rather get a nice 1911, garand, or mk12 for that.

I'm not sure if they do this particular conversion, but DJ Getz Firearms in PA is the closest dedicated HK smith I know of.  You can find him over at hkpro.

I'm not sure if they do this particular conversion, but DJ Getz Firearms in PA is the closest dedicated HK smith I know of. You can find him over at hkpro.

Never heard anything but good reviews on his work. I think he does alot of work on the mp5 clones too.

^ Edit dj getz makes his own mp5 clones with very good reviews

I always thought these looked similar to those types of HKs:

 

http://max-11.com

 

They have semi-auto versions now. Not sure which, if any MACs are NJ legal because I know you guys have some pistol weight thing. But you can get them with 16" rifle barrels which should do the trick with a pinned stock.

I always thought these looked similar to those types of HKs:

 

http://max-11.com

 

They have semi-auto versions now. Not sure which, if any MACs are NJ legal because I know you guys have some pistol weight thing. But you can get them with 16" rifle barrels which should do the trick with a pinned stock.

 

I have a Masterpiece Arms mini-9 (9x19) MAC that is NJ legal, bought it as a pistol. Also a Norinco Uzi carbine.

 

IIRC only the mini was legal and what your dealer is willing to transfer is another story.

 

The MAC carbine they make looks good to go if the stock is pinned, I like it a lot

 

Regarding the USC to UMP conversion:

 

http://www.hkpro.com/forum/hk-nfa-talk/153143-trying-decide-ump-mp5-clone.html

 

Of course, that's an NFA clone the OP is looking for...but the guys outlined in that thread can do a 16" build no problem