I think it a bit too severe , unless he also had engaged in some type of criminal activity (either prior or since) or they had reason to believe he was a danger to society.
Still a lot unknown about his character but the article never mentioned that he had any kind of previous criminal record.
To me, giving 7 years was -- them sending a message , perhaps even to soothe the mmffking anti-gun liberals.
His age, previous service and apparent good character(as a law abiding citizen having served with honor)should have garnered him more leniency imho.
3 years to be suspended and maybe a 500/1000 dollar fine, seems about right to me..--Tyr