capturing very fast moving subjects such as bullets or freezing exploding objects requires very short exposure times
most normal flash units can get to 1/20,000th sec flash duration (eg. at 1/128th power output), but even at this duration, a bullet can move 5cm making them blurry and almost invisible
Vela One high speed LED lights have a brief pulse in the range of 0.5-5microsec (1/2,000,000th sec - 1/200,000th sec) although the GN is around 1.5m at ISO 100
you will also need a high speed trigger device to fire the light source at the precise moment