The movie
Band of the Hand (Michael Mann, 1986) features a brief use of a paintball gun.
At the beginning of the team's training, Carlos (Daniele Quinn) takes a ball on his heavily padded flak vest.
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.
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.)