The final gunfight from Open Range
All the shootouts in Ronin
The end of Hot Fuzz
. C'mon now, gun battles can be fun too.
The finale shootout at the Victory Motel, and the raid where Exley gets his nickname, "Shotgun Ed".
The train station shootout at the end of The Untouchables
The hotel shootout at the end of The Way of the Gun
Also +1 to Heat, The Matrix, The Kingdom, Unforgiven, Tears of the Sun, and the final raid in Proof of Life.