speedturtle - 5/3/2010 4:13 PM
DmikeM, I saw your post about your FPS data and they seemed to be really low. How about trying it out with the JM spring and the stock piston seal? Is the JM seal too tight? Play around with some washers at the rear of the spring to increase preload if the space can accommodate them. Do you have an specific FPS goal in mind? Just curious. 
I would like to get close to the number you are seeing. But again I am at 6800 feet above sea level so I will be short about 20 to 50 FPS. The B26-2 .22 cal has the JM Euro spring and the Apex small in it now. There is a considerable length difference from the factory spring but no real improvement. I added some buttons and cleaned it up nice, the gun cocks and shoot like a dream but just not as strong as it should be. Seriously I was able to punch a paper .177 cal sized dot from about 35 yards 3 shots in a row with it. Then had a nutter venture into my shooting range. The shot went through his chest cavity exactly where I aimed and lodged just under the skin on the other side. So the gun is accurate and deadly but shoots a little soft.
I tested 3 springs in the B26 .177 this weekend and decided on a shorter RWS 320 spring that Mike sent me. I do not have the actual number with me here at work but will try to post that info once I get home. But they are about 150 fps short of your crosman spring numbers if I remember right. Very accurate and also deadly, but I think somewhere in the 850 fps range would be more appropriate. BTW that RWS 320 spring shoots like butter and the shot is just a thump and straight back no twist or vibrations.
