the 502b flashlight has springs in both ends and can absorb the setback of the battery.
I think that R2 led is the best and cheapest choice to throw.
I have a sipik sk-68 flashligh attached to my home defense shotgun, 12-70 gauge, but my range is about 50 meters or less.
Regards.
Ah .. not, I have blocked the mobile part of the zoom.
Thanks.
PD: Thinking it well ... serious funny man ... a shot in flood other one in throw 
I didn't think to ask.. will the recoil cause the laser to shift even slightly? I'm not familiar with how solid these laser/flashlight mounts are.
Yes the laser will move I highly recommend you completely disassemble it when you get it. The laser has 2 spring in the horizontal plane about the size of pen springs that absorb the recoil forward and backwards. On one of the lasers I received the front spring was jammed in sideways, had you fired a weapon like that the laser would have been destroyed. Some people have replaced the springs with heavy duty springs. I just tighten them down so there is about one quarter inch of movement. The laser may come out of alignment after a couple clips but usually settles in after a while.