Il simply say this about an mg42. I'd rather not get shot by it.
You'd rather not get shot by anything, if you take my advice.
It usually doesn't hurt right away but give it an hour and you definitely know something isn't right. Unless that bullet penetrates something vital, like a lung or a large muscle it can pass through unnoticed.
When I got my first wound on the front of my lower leg, I didn't really feel it. I though I had run into a stick. It was about an hour later that my leg felt like someone was hammering on it.
Belly wounds??? Depends on where it passed and how close to the diaphragm it was, or how much bleeding is involved. Get a bullet passing through a major artery and bleeding out is just about guaranteed, before anyone can stop it effectively.
Don't believe the movies, where they manage to get a tourniquet in place and the bleeding stops. Maybe in the very odd case.
One thing about bleeding out, no pain is usually felt. Shock saves that at least.
Getting shot is not a pleasant experience under any circumstances and the repercussions can be horrendous.