No physics from me brother. It was a miracle that I pulled off a B in Physics 101 at Mizzou. Just keep repeating "It's vectors" wink

From Peter Blakeley "Successful Shotgunning"

[Linked Image from photos.smugmug.com]

Slow motion SxS, O/U and repeater recoil (I've always learned best with pictures) I don't see much deflection down, but certainly laterally with recoil with the SxS

https://depositphotos.com/154090746/stock-video-clay-target-shooting-magic-with.html

Live action (the first minute) from the 1912 Stockholm Olympics. Not at a good angle to see any sideways flip, but I think there is a difference in the up-flip between the SxSs and the (oh the shame) repeaters