Was playing around in Photoshop, and with all the interest lately in PDW's, and the continued interest in MP5/HK94's, something crossed my mind:
How about a blowback upper group in 9mm/10mm/etc (pistol cartridge)?
There's a market that exists for these types of weapons. Given the rise in cost of ammo, 9mm still stands in the category of fun and cheaper to shoot. There are also alot of people who want MP5/HK94 styled weapons, but most of these people don't want to go out and dump the dough for a real HK94, and the very few clones have reliability issues, or are very expensive.
If RA could retain the QCB aspect of the XCR, but design a blowback 9mm upper that could be retrofitted to an existing lower receiver, i think it would = WIN.
For those hardcore, one could SBR, then pull the 16" 9mm barrel and install a 5" 3-lug in a matter of minutes, it an XCRable 3-lug existed. You could then have an SBR SMG-styled weapon.
For the magazine, a mag-block could be used, and the magazines could be the Colt Style 9mm stick mags or maybe even modified UZI or Sten mags. With a blowback, virtually the entire gas system/piston/etc. would be eliminated, and allow the upper to be alot shorter. The side-charging system could be replaced with a forward-mounted charging handle, that directly connected to the carrier, in a cocking tube-style configuration.
I know, I know, all easier said than done, but I'm just brainstorming here. I'd be all over something like this. 9mm is incredibly easy to suppress, as alot of standard off-the-shelf 9mm is < 1000 fps and results in the "hollywood quiet" that everyone wants, and this would be an added bonus.
I know that Professional Arms is doing something similar with their MP5 clone, but we're still talking about several thousand dollars by the time you buy one and get any conversion barrels for it. Standard MP5/HK94/clones require a smith with a press and MP5 knowledge to do a barrel swap, and it is neither cheap nor easy to do.
I like the look of a lower specially made (tapered at the magwell) to accept stick mags only, but even a mag-block would work and look good.
Thoughts? Am I crazy? Production/R&D costs too high to make this a marketable product?
Link to first concept.
[UPDATE] May as well post my updates, since all we have is gun porn at the moment!