Some of my guns are leaking : Diana P1000 , but I don't like it so ..it doesn't matter . Kalibrgun Carbine .25 also leaks and I would like to fix it 'cause it's a great gun to shoot.One or two others are leaking so slowly it's not a real problem...others , Cricket , Crown , Ataman , Wildcat keep their pressure during several months.
Leaks , once they are detected , are not very difficult to fix :most of the time just change the Oring by another one of same , or better quality , from a serious brand. To find out the leak is sometimes more difficult , especially if it's leaking very slowly. I use inflatable balloons on the barrel muzzle and on both ends of air tubes ; water and soap for others places around the action...lube the Orings regularly also could prevent them to leak.
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