A cap gun has no projectile- airsoft does.
you can't!
While velocities vary from model to model, an airsoft gun is usually safer than a bb gun because a plastic ball is less likely to penetrate an object than a steel bb.
Air soft is the common term, soft air is the correct name.
Anything is possible but not likely with air soft. But they do hurt when they hit you. Simply don't shoot anyone with an air soft gun. Treat it like a real gun.
For an air soft gun it's average. Air soft guns can reach 400 FPS.
An air soft gun can possibly kill a rattle snake but it depends on the gun and where you hit it
A BB gun has a very hard projectile and will cause more damage to a person than an air soft pellet.
An air soft gun would hurt much more than a Nerf gun. A Nerf gun only shoots foam at an extremely slow speed but an air soft gun is pressurized and shoots bb's at a much faster speed.
No.
No
No
Colt makes a 1911-A1 Pellet gun made by Umarex. I know of no BB gun unless you are asking about an Air Soft gun. The Pellet gun is very good. I can not answer about an Air soft gun.