The movie
Blown Away (Jeff Bridges, 1994) features the use of a (fictional) paintball mine in a training sequence.
James "Jimmy" Dove (Jeff Bridges) is teaching a class of bomb-squad
trainees, and holds up a "Bouncing Betty" type of land mine in order
to describe how it works. As he does so, he notices Anthony (Forest
Whitaker) is not paying attention and calls him to come up front.
As Anthony walks up, he steps on what he's told is a live mine, hidden in a ventilation grate in the floor.
Jimmy and the rest of the class clear the room, and Anthony attempts to disarm the mine.
After a few moments, Anthony stands up and proceeds to step off the grating.
The mine pops out of the grating....
... and detonates.
The mine thoroughly covers the entire room in blood-red paintballs.
And finally we see Anthony, also well-coated in red paint, striding out of the room.
While most of the hits do in fact look like actual paintball strikes, the mine itself was a fake