Probably an inspector's initials
GSW means "Gun Shot Wound". GS is an abbreviation for "Gun shot".
It's a 12 Gauge Pump Shot gun with receiver made in France.
You compare the rifling marks on the bullet to the rifling in the barrel. You can also compare the firing pin mark on the primer to the firing pin on the gun.
No
they were single shot pistols that had to be reloaded after each shot, originally used by loggers to mark trees, and then turned into sport once people inevitably started shooting each other. Related link is a picture
To hear the gun shot at the start of the race
Yes.
There is no patron saint of gun shot injuries.
My gun.
a gun.
none
@ the turn of the century