Rough worksheet.
Velocities for 10 shots 10.34 gr JSB from TM 1000
BCs worked from Dave's Chairgun calculator.
Each shot's velocity measured at V0, V6, V10, V14, V18, V20 yards (operator selected).
Working through some of the other range spacings eg., V6 yd to V18 yd etc gave very good BC coincidence.
Lifting the power/velocity from 14.6 fpe/797 fps to 16.7/852 seemed to lower BC at the same temperature and atmospheric P from average 0.0263 to 0.0252 for a similar string.
From one rifle, one set of conditions, so no great conclusions. Other barrels and conditions may produce other results. I think I am seeing different results between a freshly cleaned barrel and dirty barrel; and also after shooting other (dirtier) pellets of perhaps different alloy.
8.44 gr JSB are consistently giving me BC of 0.022 or a tad lower to 20 yards from this barrel which is pretty much what others have found.
When I can get to my farm range shortly to find the range limitations of the Labradar with the various calibre pellets.
The diagnostic downloads seem to give an average of two readings per yard of range.
When I can combine the Labradar data with slow motion through-the-scope video from say ten yards, to whatever the limits are, then some interesting correlations may appear; like what is the velocity, and at what actual range do some pellets, that have seemingly traveled with stability, begin a reverse spiral. eg., is it when G acceleration changes from - to + at/after the trajectory apogee (as I have long suspected).
Just thought some may find some interest.
Regards, Harry.
