I had three uncles on my fathers side, all with a half moon scar in their right eyebrow from the same scoped 300 Mag.
It's not the rifle or the cartridge. It's the idiot pulling the trigger. (No offense intended.)
When you have multiple shooters being injured by the same weapon.... something is wrong. In this case, my guess would be one (or more) of the following:
1. Stock shape. If the stock is "all wrong" for the rifle, it can set the shooter up for scope bite.
2. Scope mounting. Set the eye relief wrong, and have the scope back too far? Yea... it's gonna give you a little 'peck' on the forehead, when you hit the bang switch.
3. Idiots. If you don't know how to hold a rifle, it quickly becomes apparent with magnums and big bores. Just because you're the "crack shot" in your family, with a .22... doesn't mean you actually have good technique.
You don't need to be big. You don't need to be tough. You don't need to be strong. To successfully shoot one of the big bores, you just have to have good technique.
I verified this for myself during the "learning curve" I went through, while shooting all of the rifles/cartridge listed in my previous post (and more). I made some mistakes that were violently
pointed out by the rifles. The only evidence you may find today, is a small scar from a .416 Rigby scope bite. It was my fault, and I knew it as soon as I touched the trigger.
The biggest thing you can learn from the "big boys", is how to shoot the smaller stuff even better.