Our Avenger has been a bummer — one of the two cartridges didn’t work out of the box. It doesn’t advance after a shot. You can disassemble the cartridge and tension the spring. Unfortunately, the gun loses about 500 psi overnight! There are a few other problems too — front rail wobbles even when tightened, the barrel shroud slid forward about 1/8″ and has oil leaking from it. We’ll be getting a replacement early next week.