The movie
Jarhead (Jake Gyllenhaal, 2005) mentions "paintball bullets"...
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"Them paintball bullets... they hurt?"
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Yep! The shop glasses aren't even remotely safe for paintball, but at least they showed him wearing
something.
This is another situation where they're using AR-15/M-16/M4 rifles,
which of course can't fire a proper paintball. The green magazines and
bolts,
however, likely indicate they are using Simunition type ammo, which fires a bullet-shaped frangible plastic projectile.
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Regardless of whether or not you can say they're using "paintball guns", wouldn't that be an awesome place to play? :)