Goblin Sharpshooter Trigger Question - Magic?

So, I'm curious about the rules pertaining to Goblin Sharpshooter. Let's say I have 5 1/1 goblins and a goblin sharpshooter. My opponent then has 5 1/1 creatures as well. I declare my attack with my 5 1/1 goblins and he blocks all of them with his 1/1 creatures. Could I then use my Goblin Sharpshooter to ping for 10 because 10 creatures go to the graveyard? Or would I only be able to untap the Sharpshooter once?