Electric-ignition 12ga

I sometimes find some interesting articles on the site Spacewar.com and I found this one about Metal Storm’s new “MAUL” 12ga electric-ignition underbarrel accessory gun for the M16 / M4: http://www.spacewar.com/reports/Metal_Storm_Completes_First_Shoulder_Firing_Of_MAUL_Shotgun_999.html
Apparently it weighs only 1.8lbs which is due to it not having moving parts other than the trigger. If it is like their other products (grenade launchers) than it is a muzzle-loaded design where the barrel is also the magazine tube, and each cartridge is electronically ignited with no ill-effects to the cartridge behind it as it propellant is ignited in those shots.