The movie
Band of the Hand (Michael Mann, 1986) features a brief use of a paintball gun.
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At the beginning of the team's training, Carlos (Daniele Quinn) takes a ball on his heavily padded flak vest.
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Joe (Stephen Lang) holding a Nelson Nel-Spot 007, berates him for not
using cover, and not supporting his teammates. The cocking knob
of the marker can clearly be seen above his left thumb.
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Carlos, still not getting the point, takes a second ball from Joe.
(Note the slight difference in impact point of the first ball- in the
first photo,
it's slightly overlapping the center seam. In this photo, it's nowhere near the seam.)