Sheister: About 25 years ago "I" discovered the "seasoning phenomenon" of the 22 L.R. ammunition in my Rifles.
I only wish I had "discovered" or known about it 35 years prior to that - it would have saved me a LOT of ammunition and consternation!
For instance I have an exceptionally accurate Remington 40-X in 22 L.R. that repeatedly took 10 to 20 rounds of the new ammo to settle down (season itself) back when it was new to me - and I was doing accuracy testing of various munitions.
I have NOT noticed the "seasoning phenomenons with the copper jacketed 17 HMR ammo in any of my several 17 HMR Rifles.
I am so happy you had a great day at the range Saturday.
My Elk Hunting partner and i had one of those great range days (no wind, no mirage, bright sun at our backs and 58 degrees!) yesterday as we sighted in three centerfire Elk Rifles (338/378 Weatherby Magnum, 300 Winchester Magnum and a 7m/m Remington Magnum) - no seasoning needed there either - thank goodness!
Hold into the wind
VarmintGuy