grayfox Wrote:Example: take uniformly sized and re-sized cases, uniform primers (same lot), a single bullet of some percentage consistency (0.3 gr/100 or so), a single lot of powder, an overall length (+/-0.003 for example) or OAL, all within some manner of tolerances, and powder that is weighed and held to, say, +/- 0.1 gr accuracy (out of say 30 grs) of the powder scale. All of those variables have some small % of variability, so if a load, say, exits the muzzle at a consistent node/MV/angle/etc, then one can say such a load could be accurate in one's rifle. As long as you can continue to produce this load with that process and those tolerances, then its performance will be in accordance with the % deviations of the variables listed above... some of which won't have a discernable amount of MV delta, but some will. In those cases, comparing one set of cartridge load combo "A" against a differing set of combo "B" (ie, increasing powder charges for example), one can use es/sd of those load sets as an indicator of potential accuracy. [Certainly more load sets of equal combo are better than a single one.]
While that sounds great in theory, velocity variation doesnt work that way. If it did, youd see the same ES/SD for each powder charge for a given load workup, but we all know thats not true.
On top of that, lowest ES does not repeatably correlate to best accuracy. Yes, its necessary at extended range, but inside a few hundred yards if you actually measure both accuracy and velocity for each group in load development you will see what Im saying. Best accuracy will happen at a certain powder charge or seating depth, and lowest ES will happen at a different one.
As to Harpoons example above, being a great shooter doesnt mean you have a great understanding of statistics and interpreting data. Sorry but I dont care to spend much time watching YouTube videos, so if theres a particular point youre trying to make in that video just say it here.