I charge a 42CU 3000 psi paintball tank with a stirrup pump at home. See how many pump strokes are required and how long it takes to get the bottle from 0 to 3000 psi. I charge two of these bottles on the day of the video. This is the second one. Cheap paintball tank charging with no need for diving bottles or compressors, but with a price to pay in effort! I am glad that I decided to go this way. DIY paintball bottle refill.