There's starting to be an interest in quick-remove barrel systems for ARs, as I mentioned in an earlier post. The photo. above is from the MGI QCB System; at Blackwater earlier this week Rob Pincus had a breakdown from a different firm.
Obviously, ARs of all type break down pretty easily — pop the two pins and separate the upper and lower receivers. The advantage of being able to remove the barrel from the upper receiver is, as you can see from the MGI pix, the overall package is much smaller and can easily fit into a normal-sized briefcase.
Last week on the podcast, we talked about dedicated firearms, both handguns and long guns, for chronic travelers. I had talked about a breakdown Winchester '92 in .44 Magnum. For my own case, I had rules out any semiauto because I travel a lot of states with their own archaic "assault weapons" ban, e.g., California. However, if my travel didn't include CA, CT, NJ and MA, a briefcase-size AR would be a compelling choice.
My only caveat would be for a dedicated travel gun that was going to be broken down a lot and schlepped hither and yon, I worry about bits and pieces of flotsam and jetsam ending up in the lower receiver and gumming up the trigger mechanism. I might look at a unitized trigger such as a Timney or Pact as a bit more durable system and still cover the lower receiver.
The break-down AR Rob Pincus had at Blackwater was from the Dry-Fire Training Pistol Company. You can see a video of it in action on the page:
The system is designed to use a low-profile gas block, and allows your AR15/M16 to be broken down into three major components, for quick barrel changes, as well as covert concealment (DISCREET CARRY), or storage. A 16-inch barreled AR15/M16, with a collapsible stock, red dot sight, and two 30 rd. mags. can be carried in something as small as a briefcase. Full assembly and loading to firing condition can be accomplished in less than 30 seconds, with ease. This conversion replaces the existing barrel nut and fore end.