When the gun fires and sights lift you transition to next target. Versus typically after second shot people will see sights lift and come back down to where they were aiming and then make the transition. You will hear JJ refer to that as flatlining.
My gen5 is way slower than my Gen 3s. Same ammo, Gen 5 will Chrono 128pf and I’m at 135-137 in my Gen 3 G34 and wife Gen 4 G17 chrono at 135+ as well. I chrono around 130 with my KKM barrel in Gen 3 G34 as well.
Not always possible in Southern Oregon. One range has no shade so your at mercy of cloud cover. I’ve tried to put a white target on top of screens. Sometimes it works.
Only other thing that I’ve seen cause big variation is bullet set back but that usually make rounds way too fast.
Yes it obviously fired out of battery but I would say the main cause was the bullet setback on a stepped case. It might not of blown out of it wasn’t a stepped case. Don’t know what press the ammo was reloaded on but my 1050 gets stuck on stepped brass and won’t resize cases. Wonder if press could have had similar issue on sizing/depriming and didn’t fully resize and that’s possibly why round wouldn’t chamber all the way if you don’t case gauge ammo.