I bought a refurbished jet 1 in .25 cal. There was no air in it when I opened it so I pumped it up with a hand pump and when I released the pressure pressure release valve on the hand pump the fuse on the gun went down to exactly 200 bar. I got 3 shots then it was empty. I tried to refill it and every time I pumped air sounded like it was coming out the barrel so i unscrewed the air tube and put about 5 drops of silicone oil in the little hole on the thing the air tube screws into I put the tube back on and hooked it up to the hand pump and started pumping and the leak stopped. I pumped it up all the way and again the release valve made the gun drop to 200 bar only this time I fired 3 shots. They were super loud and the pellets punched right through a metal craftsman tool box and the gauge barely moved from 200 bar. Now I'm hoping it stays working. Anyway I made this post to maybe help anyone experiencing the same problem and it will also get me a little closer to being able to reply to people on here. I've seen so many guns I wanna buy but can't because I cannot contact them.