Large Chrono Variation in Light 45acp
Been reloading for some time with a Dillon 550 and generally download to point that 19ll's cycle well. I prefer light plinking loads.
Recently got a Kahr P45 with 3.5" barrel and loaded a bunch of 200gr LRNFP with 3.3 gr Clays. Gun functioned properly with good accuracy. (This load works well in my 1911's also).
Yesterday I used my new Chrony F1 for the first time with these loads and the variation in FPS seemed way too great. For example, out of the 50 bullets fired I got a LO 510, HI 618, and everthing in between, with overall avg 576 fps. I've gone back to my Dillon and weighed a couple dozen drops and they all were very consistant with at most a half tenth grain variation...guessed at as the Hornady scale only shows tenth's.
What kind of variation in FPS should I expect? Is this normal? Suggestions, advice, appreciated.
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