In response to an earlier inquiry.
Weighed about the last 100 pellets in a tin of .20 cal JSB exacts on the new scale. The pellets were not labeled for weight on the container. The library reference indicates that these are 13.65 grains. I repeated the weighing process of the first 20 pellets or so, and found very good reproducibility of the initial weight displayed, so I only weighed the remainder of the pellets once.
The pellets I weighed had a skewed distribution toward a bit heaver average, approximately 13.75 gr, range 13.95 gr to 13.40 gr with a single "ringer" that weighed 11.80 gr, but visibly was indeed a JSB Exact. That's a magnitude variance of about .5 gr (3.6%), or +/- 1.8 grains (1.8%), excluding the pellet weighing 11.8 gr). More than a few had some deformation of the skirt. When I saw these, I used a pellet seating tool to straighten the skirt and then re-weighed the pellet. At the end of the process, there were no free lead shavings left in the container.
Empirically, the R9GF still likes these pellets, but the next time I shoot for best groups, I will pick pellets from the same weight bin. I also plan to run 10 of the pellets with the exact same weight over the chrony to check the velocity and calculate the FPE of the R9GF and check the variation of velocity and FPE due to the springer independent of any weight variation in the pellets. Variation in energy output of the springer and variation in pellet weight would be additive in effect with potential to cause variation in accuracy at the target, but on average, would tend to cancel -- it would seem just as likely to have a hot shot with a heavy as with a light pellet, for example, one result tending toward the norm and the other increasing the over all deviation.
