Lube the bolt to almost dripping wet. I use Mobil 1 or some other synthetic auto oil, no need for high price gun oils. If that doesn't help, I would send it back to SW-- before spending a lot of money and wasting time, ammo and frustration. I forgot to mention-- lube it up, however don't get excessive oil in the chamber of the barrel. As the parts get broken in and mated up. less oil on the bolt should be needed.