Daryl, Did you look at the patent page on the website? Patents
Wow they have a bunch.
I agree with you about headspacing. I guess I am not sure what TV is trying to do with their designs. Is it to eliminate brass or design a combustible case?
Reading patent 8561543 it is apparent that the case is is made mostly of plastic and fiber reinforcement. The patent is not specific but rather lists almost every plastic as a possible choice so as to not limit it. (in fact I am surprised the list was allowed since it is so broad and all encompassing) Also it uses the word ductile which basically means it can expand and seal the chamber.
The other thing is what was the original design request of the US military. All I knew was they wanted to change away from the 5.56 to something bigger. (Heavier) Oh boy lets have the grunts hump even more weight into the field. Since generals rarely get off their asses and hump the boonies.