Michael Mann made some really good gun related movies. He added realism that many of the others lacked, such as constant reloading. I always felt that without a doubt this, along with "Crime Story", was unquestionably some of his best work.
http://www.youtube.com/user/billt460#p/f/141/USZARLgMl6oI have the Collector Edition of "Heat", and it comes with the DVD titled, "The Making Of Heat". It shows the extensive firearms training all of the actors went through. Val Kilmer said the biggest compliment he received about the movie was when an Army officer was so impressed with the shootout scene he showed it to his men and said, "If you can't change magazines faster than that actor, I don't want you in my damn Army!" Kilmer laughed and said he thought was pretty neat. His mag swap in the middle of the shootout while laying down cover fire for Robert De Niro was very well done.
When they filmed the bank shootout scene they could only film on Sunday morning, and used over 400 rounds of blank ammo
per take! It was one of the best modern day shootout scenes ever filmed. Bill T.