I’ve only fired a semi-automatic once in my life at a hunting cabin with the Rotary Club members. Darn near sat me on my rear! ...and is the only gun I’ve ever fired.
IOW you actually do know almost nothing about firearms but have, at the same time, strong opinions. Good work.
First, it's not the semi-automatic part of that that has the effect. It's the large caliber of what was probably a hunting rifle - which is not generally a characteristic of the guns they are talking about.
That wouldn't happen with an AR-15...even for an average child of about 8. Drill Sergeants would demonstrate the lack of recoil by placing the butt of the weapon against their 'manhood' and firing it.
That's part of the silliness of the debate - is that people are being given the impression that they are talking about completely different items that what the banners are attempting to legislate. As I noted, an AR-15 is a light-rifle.