I'm with Ian and others on this, hero or not stashing an unlicensed handgun in your house, pleading guilty and then being unhappy about the sentence doesn't wash with me, and obviously didn't wash with his CoC either. Afghan trauma might be defence for the odd angry outburst but not for stashing illegal weapons in your pad for years on end.
Reference CO's orders and court martials, serious offenses go straight to court martial, I would expect this to be such.
As a final thought... Who would like to be served by an Army where it was ok to acquire and stash extra-curricular guns as long as you were SF or a "good bloke"??