I’m with you about never letting them know about this. Honestly, I’ve never thought this could possibly be an effective line of reasoning with them.
Quick test: If you were a gun-grabber, what would YOU conclude if I told you a Ruger ranch rifle was almost exactly the same as an AR-15?
A. Gee, I didn’t know that. We better leave those AR’s alone since they’re basically the same as other popular rifles.
B. Gee, that’s scary. Better ban them all.
We should be discussing a comparison to the size and velocity of a pitched baseball.
UKistan & Aussiestan banned all magazine shotguns IIRC.
Watch for demand for ban on 870 mag extensions next.