My friend has a .50 calOptima 26" barrel.The problem is that his primers are not going off.He is bringing it over Sunday for me to look at,and I was wondering if any of you have heard of this happening.I believe the pin is not hitting the primer,or atleast not hitting the primer hard enough.He said sometimes it leaves dimples,but the cap doesn't go off.Sometimes it does not leave a dimple.He has also thrown the old caps away,and bought brand new caps w/ the same results.

He says when the primer does not go off.He switches primers,and tries again,then switches primers,and tries again....eventually after 4-10 tries the primer will fire,and thegun will go off.

Could it be a corrosion build up around the firing pin?I'm going to shoot some cleaner in there first I think...Any help is greatly appreciated.Thanks guys!