PCB Battery contact in pill

[kmm5117]

So I'm having a little trouble with a build I'm doing, for some reason I can't seem to get the battery contact PCB tightly seated inside of the pill. I'm using an S4 host with a 18650 and a 450nm diode (around 50mW). I completed the build but wasn't quite happy that the contact board wanted to fall out with out the battery in. Once the battery was in it seemed like I had to mess around with the tail cap to get it working, and once it came on it was fine. But after messing around with the tail cap, I fried the diode, I'm guessing i shorted it out. What I'm asking is how can I properly secure the battery board in, it just seems a little loose, I do have the brass ring that came with it, but that seems to make it too tight, especially with the small wire I have to maintain negative contact with the host.

Does anyone have any suggestions? Possibly thermal adhesive or something? By the way I am using a rectangular XDrive for this setup