I got a KWA km4 (2gx) and noticed that whenever I don't shoot for a while (45 mins) the hop up seems to stop working. So when I start shooting, the bb's drop after about 30 meters. However after a couple of rapid follow up shots, the range is doubled, and the bb's fly straight. I therefor always have to shoot multiple shots in quick succession for the bb's to reach their normal flight path.
I have already checked the bucking, and everything seemed to be fine. Has anybody else had the same problem? Does anybody have an idea how to fix it?