Hot Melt Experiment -- How Much Heat?

[PowerFade]

I'm experimenting with an old driver head by adding 4g of hot melt glue stick pieces through the hosel. I've heated it up twice with my heat gun and I still get a bit of a rattle. I don't want to overheat the head and ruin the finish. How much heat will totally melt the glue? How long should I heat it? Anyone have experience with this?? Thanks in advance.

Through many online searches and calls to craft stores, I belive the hot melt glue melts at 350*F (and will be stable up to 142*F) and the low temp glue melts at 250*F (and will be stable up to 120*F). Which means don't mess with too much heating when the head is shafted! Thanks to all for your comments.