The Personal Defense Weapon concept goes back to the 1990s and only slightly predates the Stargate project. As we know, two weapons were developed for this project over its lengthy NATO trial. We have the FN P90 of Stargate and the Secret Service and the MP7 of the SEAL Team 6 and the GSG 9. The FN P90 has a companion sidearm, but the poor MP7 seemingly didn’t have such a companion. Or did it? Well, Heckler and Koch dreamed one up in 2003. Thus the HK UCP was born.
The project lasted six years, and it appears that three different prototypes were developed along the way. The prototypes all appear fairly different, and the final model of the UCP looks quite modern and high speed.
The HK UCP – A Gun of Many Names
UCP seems to be the most widely accepted name for the pistol. The UCP is printed on the side of the slide of the many prototypes that were produced. What does UCP stand for? Well, according to most sources, it stands for Universal Combat Pistol, although I’ve seen the name Ultimate Combat Pistol also listed.
I emailed HK but did not receive a reply to clarify. With the USP standing for Universal Service Pistol, I’d say it’s safe to say that the U stands for Universal. Besides UCP, apparently, the gun was also occasionally referenced as the P46. The 46 references the 4.6x30mm round the weapon fires. The little 4.6x30mm round isn’t quite your traditional pistol round.
The Little 4.6
The 19 in 9×19 standards for the length of the case. The 30 in 4.6×30 stands for the case length as well. As you’d imagine, the case length is quite long compared to traditional pistols. It’s also a bottlenecked round, which is rare but not entirely new for handguns.
It features a very small projectile, approximately .18 inch in diameter, with a spitzer shape. Spitzer is a fancy way to say the projectile is pointy. Most pistol rounds, really all of them, feature a rounded nose projectile. The spitzer design makes it a little better for long-range shooting and much better for soft armor-piercing capability.
One of the big features of the PDW project was its great capability to penetrate soft body armor and steel helmets. This is why the PDW projects rejected your traditional pistol rounds in favor of these little stingers.
Inside the Universal Combat Pistol
The UCP looks a lot like HK handguns produced in the 1990s and early 2000s. It’s a big rectangular design that borrows a lot of design cues from the USP and P2000 series handguns. HK created the first polymer frame handgun, so it’s not a surprise they did the very same with the UCP.
The polymer frame utilized a rather wide grip and the 30mm long projectile renders the grip somewhat awkward. I’ve never handled the UCP but I have handled the FN Five-SeveN, and I’m betting they are similar. The grip feels a bit like gripping a board. It works but doesn’t bring that CZ-like grace to the grip of the gun.
Oddly enough, HK implemented a standard Picatinny rail instead of the silly proprietary rail system we see on most HK firearms in this era.
This is a double-action firearm that uses the same modular trigger system as the P2000 and USP. Users can switch the trigger to several different safety and trigger configurations. This includes DA/SA guns with safeties, DAO only, DA/SA with decockers, etc. All those various ‘Types’ of USP would likely have applied to the UCP.
HK also used ambidextrous controls that can be described best as massive. This was never intended to be a concealed carry handgun, so HK didn’t hold back. The big safety/decocker design makes it easy to use with gloves, and it’s tough to miss.
On top of that, the UCP utilizes a massive slide lock. As a dude who constantly pins down his slide lock and makes it useless, I appreciate these big HK-style slide locks. We also get the trigger guard magazine release that I’ve also always loved.
It’s a Big Girl
The HK UCP came with a long 5.11-inch barrel. The 4.6x30mm round works best from a longer barrel. Unlike pistol rounds, the PDW cartridges function best with barrel lengths of 10.5 to 7-inch barrels. So a longer 5-inch barrel gives the gun a little extra oomph for that 4.6x30mm round.
The overall length is 7.87 inches long, and even though it is quite large, it weighed 1.87 pounds. It’s fairly light for such a large gun. That long barrel got a fair bit longer with a suppressor. No one made a commercial 4.6 suppressor, so HK teamed up with B&T to produce a suppressor for the gun.
I’ve never handled the UCP, but I’d imagine it handled and shot like the FN Five-SeveN. One of the most impressive things about the FN Five-SeveN is the magazine capacity. The UCP brought their own impressive magazine capacity of 20 rounds with a flush-fitting magazine, meaning the gun has very little recoil and handles quite nicely outside from the awkward grip.
The Weirdest Part
Believe it or not, we have reached peak weird, or well, I guess peak innovative. The weapon doesn’t use a short recoil design. Nope, it uses a delayed blowback system. Which particular system? I’d guess that it’s roller delayed like the HKs P9S, but I cannot confirm. It’s interesting, and the use of a delayed blowback system makes sense with the little 4.6x30mm round. It would provide a reliable and capable action.
The UCP promised to provide a companion to the MP7, but as you and I know, it never came to be. Why? Well, HK tested the firearm and developed a number of prototype designs along the way. The weapon apparently worked fine, but the downside came from the 4.6x30mm round. HK did not find it to perform suitably for defensive and duty prospects in pistol form.
As such, the UCP was quietly retired, and the project stopped in 2009. HK likely has a few of the UCP prototypes sitting in the famed grey room. Sadly we are unlikely to ever see the weapon hit production. Although, I am surprised no one has produced a pistol, or rifle, or anything in the 4.6x30mm round. A 4.6x30mm pistol certainly isn’t out of the realm of possibility, but it won’t be HK’s UCP.
