Strikeman Laser Training System

No ammo available? Train on your room or in your backyard with this great system. It is accurate and silent. But... I see no way to change the battery on the laser bullet and that means another 60 bucks on a new bullet... So, the system can be hacked to provide a better trigger system and a constant power supply. My first ideas is to make a switch on the hammer or trigger lever that closes the circuit and a little microcontroller (PIC12F683 or similar) will temporize the light on the laser. All connected to an external battery. A little hard to implement on a revolver with rotating cylinder but then there the laser must be inserted directly in the barrel with the cylinder open?

The product's web page.