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cliffspot · Veteran Member

Ok, last week I got to get some numbers at my friend's house on his Chrony. These are 5 shot averages listed as FPS/EX spread/weight in grains:
Gamo Match 865/3/7.8
Fireballs 740/12/11
Silver Sting 820/15/8.6
Kodiak 695/3/10.6
Cro Mag 795/4/8.9
Super Mag 735/12/9.4
Laser 912/3/6.9
Super Dome 830/5/8.2
Laser Sport 850/16/8.1
Super Point 815/21/8.4
Silver Bear 895/17/7.2
RWS HP 900/17/7.2
Silver Arrow 660/25/11.8
FTS 820/2/8.6
JSB Straton 821/6/8.2
JSB Exact 823/7/8.3
H&N Silh 804/2/8.8
The most accurate were the H&N and Straton; followed by the FTS. I retuned the gun after a dry fire that made it buzz (I know how dumb I am!) All I did was turn the spring around so it was a lot tighter on the guide, put some JM buttons on the compression tube, cleaned and relubed lightly. Also put in a second SS washer in the piston. Gun shoots super smooth again, maybe a bit better! Took out the trigger blade and polished a little bit on the bumps and some contact surfaces in the trigger, seems lighter now. Rechronyed using a few pellets; here's what I got:
FTS 853, Trophy 850 (didn't have these for the last test), Laser 925, CPL's 860. Seems to have picked up 15 fps with the second washer added. Waiting for more buttons from JM and the next test will be results with the piston buttoned and the JM spring and guides followed by the JM seal. Amazing how the pellet weights affect the velocities, never knew springers were that sensitive! Will try these tests with my R1 in various states of tune also. Will the heavier mass and increased diameter make the R1 less sensitive to weight? Answers forthcoming!
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