I got to shoot the HK Universal Machine Pistol (UMP) at the SWAT Roundup this week. The boys at HK had two production protos with them, about 95% of the final form. The gun resembles a sleek, polymer Walther MP-L subgun. It fires from a closed bolt, has a polymer receiver with PDW style side folder, iron sights with Weaver rail on the receiver top, and M16 (or MP5/10) style lower receiver controls -- safe/semi/full, M16A2 style pistol grip, bolt hold open. The charging handle is like the MP5 family. Magazines resemble the MP5/10, and hold 25 rounds of .45. The feed lips are set up for single column feed, like a gigantic double stack pistol mag. I found this out after trying hard to press a round through the feed lips. Oops. The gun, as could be expected for a .45 subgun, was more jumpy than a 9mm or 10mm MP5. The reps stated that it was to fill the need for teams that had .45 sidearms and wanted ammo interchangeability. People are big on .45's lately, and HK probably will be able to sell one or two of these. Hey, it's an HK -- I'd take it if you gave me one.