I was tuning my .25 cal Crown MK2 today for the JSB 34g MK2 heavies and I wanted to share the power I was able to get with the new setup. I adjusted the hammer spring pretension to 1/2 turn from max, before hitting the power wheel cam, reg pressure was at 153 bar and power wheel on 5.
This was giving me every consistent speeds at 967 FPS. I was able to sight it in at 50 yards and I was getting under 1/2” groups! The energy for that speed and pellet weight is 70.8 FPE. I have been trying to see if anyone has posted the top end power that the new crown could put out and i didn’t find any solid answers. Here is a video showing the speed using my labradar. I will add some pictures of groups later when I can shoot at 50 yards and 100 yards.