I have used elmers white glue to repair kevlar poi wicks.....
Its wicks on chains soaked in coleman fuel/white gas and spun around as performance art.
Its weakness is water, but it holds up pretty well to being soaked in white gas and lit on fire for 5 minutes or so.
I would suggest for you to find some heat tolerant epoxy. It should be a little more durable for using it on a gun. Remember to get release agent to keep it off anything you don't want stuck together forever.