The cattle gun uses compressed air to shoot out a bolt, that instantly retracts on a spring. It isn't a whoosh of air that kills people/cows.
SPOILER ALERT (don't read farther if you are going to watch the movie)
The story ended with the Sherriff finally being retired. That was the end, clearly. Realizing that the criminal world, or world of evil was far to vast for him to even make a small dent in, or even comprehend. He was the only character in the entire story, who we got any depth on. You know he comes from a family of lawmen, is married, likes horses, and a few other tid-bits. He is the only one who you get any warmth for. The funniest part is he had absolutely no bearing on the chase between Moss and Chigurh, and eventually the Mexican suppliers.
If they had a shootout ending where TLJ walks off retiring saying one of his honky catch phrases, then that would have completely wrecked the point they were trying to make. In that evil/crime/whatever is ongoing/unstoppable, and much larger in scope, and much further engrained into the fabric of society than many want to belive.
The other characters you only see in one dimension, well I guess you get a tiny bit of depth on the Moss character. In that he was in Nam, and thinks that he can do anything on his own, but that's it, and they only give you that so that you understand why he is so good with guns, and won't accept any help. The Chigurh (sp) (Sugar) character is not even defined at all. He believes that he is fate, or something like that. Dude is really scary.
I also think that they really don't want you to fully understand who everyone else is or who they work for, because you are supposed to see the story through TLJ's eyes. He never even comes close to cunerstanding who he is chasing, and how they all are linked. Let alone stopping any of the violence.
"Are you going to kill me?" . . . "That depends, can you see me?"
It is really a thought provoking movie.
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WDFW - Turning outdoorsmen into golfers since 1994.