What material is your target made of? It could be the foam is harder at the lower temps and grabs the points more. When you go to pull them out they pop off.

I never tried regular hot melt glue--always used Fer-l-Tite or epoxy. Very seldom pull a point off since I started cleaning/sanding the inside of the points--that's pulling [email protected]", and shooting all different types of targets.

Chad