+1 for keeping hands behind the cylinder. Besides the danger of chain fire, the gases/flames/hot bits coming out of the barrel cylinder gap can give you a nice burn as well.
Check the link below. One of the bad guys in "The good, the bad, and the ugly" used a revolving carbine, and of course he's holding it WRONG !!! Also, this site mentions that the original Remington carbines had much longer barrels.
http://spaghettiwesterns.1g.fi/guns3.htm
Here's the safe way to hold a revolving carbine. I don't know these folks, but Lucky Bill does it right:
http://www.coltershell.net/photos/Bl...ot/bpshoot.htm