If the bullet was a couple of inches down the barrel the primer must have fired or you have the mother of all firing pin springs. LOL. It sounds like some how the powder got contaminated and wouldn't burn. Possibly sizing die lube, or some other solvent. What is your OAL? Your load may be touching the lands and because it didn't fire when you opened the action the bullet pulled out of the case and stayed stuck in the barrel. But that would be right in the throat not a couple of inches down the barrel. It happened to me before. Try chambering a few rounds and cycling them through the action with out firing them. In all cases practice muzzle control if you have live ammo in your gun.