I recently purchased a .22 auto mag. It was jamming and as I have dicovered this is a very common problem. I then found a company in GA that sells replacement barrels.
www.kudzugunworks.com this replacment barrel corrects the jamming issue and i have had no more problems out the gun. I contacted the company and they advised that there procedure of making these barrels fixed the prevoise problems tha gun had. I highly recommend kudzugunworks.com