All reloaders make mistakes. I had to order my first collet die sleeve in 223 to remove bullets because I misread the dang scale by two grains. Lucky for me I caught the issue before I ran any of that ammo through my rifle. What was supposed to be a starting load was two grains high, and that ended up being over max listed charge.
I'm a big fan of working eyes and having all your fingers.
Machine guns are awesome until you have to carry one.