Many writers use their stories as an opportunity to get on their favorite soapbox and try to drum up reader support for their beliefs. Many times, I personally find that a distraction from an otherwise good story. This time, I think it made the story. Possibly because I agree with the author, this time.
Technically, it was above average - even if that isn't saying much - but it had few errors, at least. The characters were sympathetic and easy to like, the plot was fairly plausible even if the main character's back story wasn't, and the 'preaching' wasn't excessive.
Rabid left-wing anti-gun wackos will want to avoid this story, even if they should read it. People looking for stroke will be disappointed. Those looking for a good story with a bit of romance will love it.