First, let me say I agree with the fundamental opinion expressed in this movie: That access to arms is stupid and should be limited, if not forbidden (although I do not believe this is possible to achieve any more in the USA)
But, a movie about a grieving man who, in revenge for his sufferings, pins down an employee of an arms manufacturer and then involves her in a debate about the pros and cons of guns, is just not interesting. The setting sounded quite thrilling, but unfortunately, the entire movie is not. If the only way to produce thrills is to have a cockroach crawl around in front of a motion detector and have a sniper threaten to kill and kill a few people, then a movie is in trouble. Especially, because it repeats these cheap tricks too often.
I might agree with the opinion, but to deliver a 90 minute argument in its favour and call it a movie - that is a crime against my taste.