Quoted:
never happen. even ignoring the AP properties of the 5.7 mm. think of the barrel you would have to have on that thing, that would take all the fun out if it there. and their would be NO hi cap mags for it.
View Quote
Just to reiterate, BATF considers the 5.7mm a 'NON-sporting' cartridge, so there is no way in hell it'll ever be approved for US civilian sales. Plus of course it would only accept a 10rd mag, have to have a bbl of at least 16", conform to the AW and import bans, etc... Even if they did allow it, it would be a VERY expensive, even uglier, neutered, 10rd cap version of the real thing.
Besides, my understanding is that the gun pretty marginal at best. Apparently the 'revolutionary' 5.7mm sucks, and doesn't penetrate worth a damn. The fancy side feeding mag jams up if you smack the gun on the stock hard enough. Just my $.02.