Looks like there’s a huge misconception among gun users that this is sonoluminescence and it spilled into Wikipedia. But I’m too lazy to edit.
In every ballistic gel video, it’s the wrong size, shape, and color to be sonoluminescence. The smoke is a dead giveaway that this is combustion. Another giveaway is that sonoluminescence last 30-35 picoseconds per contraction. If you see light on more than one frame of video, it’s something else. It appears to last longer in the real thing because the bubble is expanding and contracting thousands of times per second due to a standing ultrasonic wave.
