If you don't know what Bullet Time is, better do not proceed reading this further since you might have been in another universe when Bullet Time became a well-appreciated movie and video game effect as introduced in The Matrix Trilogy (one of my all time favourite  Movie Trilogies) and Max Payne, (one of the best video games ever, for me that is). But if you do insist on reading further, here's a video clip from The Matrix where Neo dodges bullets for the first time:

There a lot of independent film makers who have low budgets and even lower technology to use for creating visual effects. But one thing that is common amongst them is they use airsoft guns as props for their films. And there are airsoft players who also want to use such awesome bullet time effect for their videos, since bullet time looks awesome in a gunfight, so if it's possible to do this effect without spending a lot of money for a camera set up like what was used in The Matrix, or do painstaking software rendition which also will take a lot of computing resources, then they'll go for it. Now it's possible if they have the creativity and lots of GoPro HD Helmet Cameras --- at least 15 of them to achieve the effect.

Marc Donahue of Permagrin Films, famous for his Dream Music Video Series, has been toying with GoPro cameras, which are also a camera of choice for many studios when they want low-cost, high quality cameras that they can mount on people and at different angles. He and his friend put together these GoPro camera on an arc rig to achieve the bullet time effect. He controls all cameras on the rig and that means at least 15 camera angles for that scene that will then be processed to polish the bullet time effect.

Indeed, it is an amazing effect and highly recommended for that airsoft film maker who wants to impress other airsoft gamers on what he/she could do. An even better thing with having GoPros as a rig is that after shooting that gunfight scene, they can just remove from the mount from the arc rig and have the helmet cameras mounted on the players for a regular airsoft game so all players can have their POV video clips of the game for additional footage to use in the airsoft video. Thus, the method becomes even more practical.

So if you have want to do an airsoft video with this effect, and belong to an airsoft team. Better require each team member to have one GoPro camera which you can later on borrow to make your bullet time camera rig. Haha!