I have NEVER had a problem with jamming, double shots or blank shots. I use Senco nails, maybe that helps? I got a nail stuck once, it was easy to fix. I'm REALLY having trouble with this gun's ability to drive a .131"3" thick galvanized ring nail into pressure treated wood that is still slightly damp. This is a problem for me because I like to use this size on decks and pressure treated wood is always a bit wet. It leaves about 1/4 - 1/2 inch of the nail undriven. The point is not to use a hammer. It drives 2 1/2" ring shank nails well and will probably drive 3" nails if I use a thinner shank, but I use Senco nails so the gun should be able to shoot them. I use a 5 hp 20 gallon electric compressor which should be more than up to the task.