Disappearing Object From Camera?

I've been working on a improved system for the first person version of my paintball gun, by basing it directly off the camera's position. It's worked great and quite smooth except for after 30-60 seconds it simply disappears from the screen. I have tried printing it's position and other information I thought could be leading to it but they indicated no problem.

Video (I'm not seeing things!): https://youtu.be/bqmANIal8kI

Pastebin of le' code(Yes ik it's probably trash pls don't kill me): http://pastebin.com/3U4WD4P5

Appreciate anyone's help on this!