My bad...I was always under the impression that the delayed blow-back design was quite exclusive to an MP-5 and it's derivatives in the CQ/sub machine gun realm. I could be wrong as I honestly have very little experience with anything like this weapon. Prior to the Corps, I had never fired a weapon in my life. The Uzi is open bolted, i believe, and operated quite differently from an MP-5 in that it crawls up a target.
This is an interesting unofficial history of H&K.
http://huntingsociety.org/HistHK.html
best,
-bear
Not Force Recon, but a direct action detachment from 3rd Recon attached to the 5th MEB (USS Schenectady/Fort Fisher) during Desert Shield/Storm/Stay. Two glorious floats.