Happened to talk to my CIII friend again and asked him about any follow up on his piston guns. Says he was running three and two of the three have gone down versus none of his DI guns. Says the piston guns have failed multiple times in different ways as the round counts stack up (kinda defeats the purpose of keeping the residue out of the working parts, if the working parts aren't reliable to begin with). He brought up a point related to that. He said his DI guns will have parts available into the next millenium, but he's not confident he will be able to maintain his piston guns into the next decade with each manufacturer making proprietary parts.
The icing on the cake was when he told me to look up a discussion started by his friends at Henderson Defense who run very high volume in their rent-a-machine gun business. Very enlightening;
http://www.ar15.com/forums/t_3_118/..._how_they_have_handled_on_our_range.htmlSeems that they only run the HK design now, and only because of customer demand.
