TFB reader, Arnaud, from France, has used his industrial skills to modify an HK USC carbine with 3D printing.  Rather than taking the American approach to modifying a USC to resemble an HK UMP, Arnaud chose to use a 3D printer to model the forearm, grip and stock partly after the Hera Arms aftermarket parts for the AR-15 pattern rifles.  For those not wholly familiar with HK’s USC model, the factory grip and stock were not generally liked by the firearm community, especially when compared to the aesthetically pleasing folding stock of the UMP.  The photo below is a stock HK USC from TFB’s Nick C’s post about the USC’s comeback.

Arnaud explains how he came to make his own parts below:

At the beginning a very standard USC from H&K, most of you , American shooters, convert them into UMP. In France, forget it, aftermarket supplier are not supporting us and law…how can I say that… is the complete opposite of US (UE is hyper restrictive). Even Hera Arms who is a German company, don’t take care a lot about European customers ( but normally making some nice parts for USC). So I have chosen to [buy] a very good 3D printer from Prusa (MK3 converted into a MK3S) to do the job of customizing my USC by myself and here is result.

Foregrip is inspired by the Hera Arms CQR and mixed with KILN design, that you can found on the web. This thing is printed with high end ABS filament from FormFutura. You can screw it directly into the USC without any modifications.

Arnaud went on to explain his process in constructing the stock as well:

Stock, is made from the same material, printed in 5 parts.
-Part 1, high density, is the connecting hub where spring guide is installed and where all other small parts are linked.
-Part 2, the grip, also deeply inspired from KILN design.
-Part 3, The main body, depending of shooter needs, can be printed longer or shorter.
-Part 4, the recoil pad support
-Part 5, the recoil pad printed in TPC , thermoplastic copolyester, reducing the recoil of the 45ACP to quite nothing, much more efficient than the standard stock
-Part 6, last one, is the cheek pad in ABS

As you can see with the logo on USC’s new furniture, Arnaud came up with his own in case he decides to take a more professional rather than just a hobbyist.  His KRX Research logo comes from a mixture of Kangourou and Roux (for his own red hair).  Arnaud said he’s got some other designs in mind as well.

Thanks to Arnaud for sharing his work with us!  What do you think of Arnaud’s 3D printing work to modify an HK USC?  Do you think we’ll be seeing more from KRX Research?  Let him know what you think in the comments section below!