Wendell: We goin' in?
Ed Tom Bell: Gun out and up.
[Wendell takes his gun out.]
Wendell: What about yours?
Ed Tom Bell: I'm hidin' behind you.
Nervous Accountant: Are you going to shoot me?
Anton Chigurh: That depends. Do you see me?
Llewelyn Moss: I'm going out.
Carla Jean Moss: Going where?
Llewelyn Moss: There's something I forgot to do, but I'll be back.
Carla Jean Moss: And what are you going to do?
Llewelyn Moss: I'm fixin' to do something dumber than hell, but I'm going anyways.
Wendell: That's very linear Sheriff.
Ed Tom Bell: Well, age will flatten a man.
[Sheriff and deputy inspecting the shot Mexicans.]
Deputy: It's a mess, ain't it?
Bell: Well if it ain't, it'll do till the mess gets here.
Llewelyn: You don't need to know everything, Carla Jean.
Carla Jean: I need to know that.
Llewelyn: You keep runnin' that mouth o' yours, I'm gonna take you in the back and screw ya.
Carla Jean: Big talk.
Llewelyn: Keep it up.
Carla Jean: Fine. I don't wanna know. I don't even wanna know where you been all day.
Llewelyn: That'll work.
Carla Jean Moss: I got a bad feeling, Llewelyn.
Llewelyn Moss: Well I got a good feeling, so that should even out.
Llewelyn Moss: If I don't come back, tell mother I love her.
Carla Jean Moss: Your mother's dead, Llewelyn.
Llewelyn Moss: Well then I'll tell her myself.
Answer: It was a different gun. He kills Carson with a shotgun, while the gun Moss picks up is a silenced SMG by the looks of it.