I don't know how you find an accuracy node with a 100 yard ladder test. Hard to see barrel harmonics with a single group of 12 bullets in one long tear. I don't go by speeds alone.
I know the Saterlee method. But, I never shoot the test at 100 yards. You not only have to look for velocity flat spots, but for barrel harmonic nodes as well. Meaning very little vertical separation between a group of 3-4 consecutive shots @ 400 yards.
Nice. Yeah I hope it starts raining soon. The forecast looks promising, but I won't believe it til I see it.Ha! I am in AZ too. I feel your pain for shooting distances right now. Hopefully monsoons will kick in soon.