Increasing a variable upon collision?

My question is, in a FPS game I want to be able to shoot a static mesh and have it destroy itself and increase a float variable. How would I go about doing that?

This question is a little vague; I guess my first question is by ‘destroy’ do you mean actually explode/break destroy in game or simply deleting the actor with a 'destroyactor node? Also, is it any mesh that can increment the float or is it specific things that do it. Overall though you’ll most likely end up using a collision box with an EventOnOverlapping node for the mesh-projectile interaction.