The Jennings J-22 and the Jimenez JA-22 are the same gun with a different name. The Jennings J-22 was manufactured as "Jennings", "Calwestco" and "Bryco". There are the same pistol, manufactured under different names after lawsuits were filed by various parties. After the Brandon Maxfield lawsuit shut Bryco down for good, the contents of the factory were sold at auction and former Bryco Plant Manager Paul Jimenez was the high bidder. Over the years, the only two changes made to the Jennings design. The first change was to the safety: The original design was a sliding safety (similar to what was used on a Raven MP-25). The newer safety design is a plastic pop-up version. With the exception of the safeties and the changes to the grips to accommodate the different safeties, all parts will interchange. The second change was to the firing pin and the take down button and is found on pistols with the plastic safety: A red rubber tip was added to the cocked indicator on the aft portion of the striker. The hole on take down was increased to accommodate the rubber tip. Broken firing pins on old Jennings J-22 pistols can be replaced with new Jimenez firing pins, but the new take down button will need to be used. Warnings: Federal Bulk Ammo: For whatever reason, using Federal Bulk ammo in a J-22 / JA-22 can result in slam fires. It has happened to me, and it has happened to other forum members. Dry Firing: Do NOT dry fire a J-22 / JA-22. The firing pin will peen the barrel and the resulting damage will ultimately cause ejection problems and misfires.