[wincy]

Is this sort of like the weapon the guy in No Country For Old Men was using?

[thechao]

That's a captive bolt gun. It's used to kill cattle for slaughter.

[wiml]

I don't remember the movie well enough, but it might have been a captive bolt gun (typically used for slaughtering livestock)?

[gruez]

Doesn't that use compressed air?

[catalogia]

The one shown in that movie uses compressed air. Some other sorts use powder charges, just like a powder actuated nailgun.

[SV_BubbleTime]

Pneumatic