In "Last of the Mohicans" when they're sending a runner with a message through the Indian and French siege lines around the fort; Hawkeye and his brother are on the wall with their Kentucky rifles, other militiamen stand by to reload; the runner starts out, an Indian rises from his cover with a tomahawk to stop him, one of the shooters nails the indian and hands his rifle back in exchange for a loaded one; another rises and is shot, and another... Deep into the woods the last warrior to try to stop the messenger rises and takes after him, the camera moves in on Hawkeye as he takes aim and pans along his really long long rifle, focuses on the lock as it cycles, then on the Indian who gets a ball through his midriff after an appropriate delay. Hawkeye had asked for some silk for patches earlier in the story, which he said added range to the shot. First class movie making to flintlock enthusiasts like me, I don't think there's any instance in the whole movie where someone was aiming a musket or a rifle with the frizzen open.
In "Lonesome Dove", when Augustus McCrae is being chased across flat, open ground by the bad guys. He's running his horse as hard as he can but not making any ground; he comes to a little ditch or gully where he dismounts, kills his horse and hunkers down behind it, laying his Sharps rifle across the carcass. The others stop and form a line in the open. McCrea thinks for a minute, then shoots a couple of rounds that fall short. This encourages the bad guys that they are out of range, so one of them walks out in front of their line and dances like a chicken making clucking noises, taunting Augustus. McCrea raises the tang sight on the Sharps, adjusts the peep's elevation for what he thinks the range is, and gut-shoots the chicken dancer. He stopped dancing.
I think Robert Duvall's western trilogy- this miniseries, "Open Range" with Kevin Costner, and "Broken Trail" with Thomas Heyden Church- are some of the best westerns I've ever seen. Duvall also made a recent movie called "Assassination Tango" which was a not-too-bad story about a hit man who goes to Argentina on a job and gets interested in the tango while he's there. It isn't the story that's all that interesting, it's the girl he dances with: Luciana Pedraza, whom he married. She has great legs which dancing the tango really show off. There's just enough gun action to qualify this comment here on a gun forum; watching her dance the tango with Duvall is why I bought the DVD.