I have a ar15 and the triggerpull is very heavy.
Is it possible to adjust this so i don't have to pull so hard before it fire's.

Be very careful when adjusting the factory AR trigger. Do NOT stone the surfaces as the hardness is very thin and an unsafe trigger can result. What I would do is to remove the trigger and thoroughly clean it. I then take a felt wheel on a Dremel tool and polish it, making sure to not remove any of the surface. I have found JB bore compound to be a good polishing adgent and it will not get into the surface it only cleans it up. After cleaning it up again and re-installing, add some lube to the surfaces and give it a try. To be totally honest, the only real safe way to get a good clean breaking trigger in an AR is to go aftermarket. Jewell, Rock River and some of the others are the way to go. You can not make a great trigger out of a turd.