N/A charging problems

Make sure you've cocked the gun before you try to pump. That takes the hammer spring pressure off the valve seat. It may also need to be charged a bit higher before your hand pump will start filling. Sometimes if there's not enough or no pressure to seal the valve, a hand pump doesn't have enough pressure/volume at the start to get the gun to start taking air without it leaking out as fast as you pump.
 
Best to isolate problem. Pressure test pump with dead-head plug (pictured), inserted in female quick-disconnect at end of fill whip (hose.) (Four Uncles should have included dead-head plug.) Pressurize pump to assure proper operation and no leaks. Release pressure, after test, with bleed valve. If pump OK, problem lies with gun. WM
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