in addition, you can add distilled water or radiator coolant to the 3 stage handpump so it wont overheat fast and wont damage the orings. the 4 stage doesnt have that option. https://www.youtube.com/watch?v=p5Dm2NNXEng
“Magnum” air rifle is one that shoots pellets at 800 – 1,000 feet per second. Although (FPS) is a by-product of an air guns power it really isn’t a measure of energy. "