In general it is legal, as long as the minor is participating in some legal form of target practice of competition.
Pull the trigger.
No.
No, you cannot.
Can I shoot 380acp caliber out of my 32 pistol?
No.
No, a minor can not shoot guns with just another minor in Canada. An adult must be present.
Yes.
500 m or so IIRC
If you shoot enough of them you get the punisher handgun for free from the merchant.
Yes you can. The bore is the same size.
Generally speaking, no. A minor, by federal law, can only possess a handgun under limited circumstances, such as target shooting or hunting. If the minor is in his or her own home and uses a gun for self defense from an intruder, in most states, there will be no problem.
Single shot 50 BMG Yes, that would work. You can shoot one with whatever handgun you wish to use. Just be sure you can run faster than whichever bear you pick to shoot if you pick a caliber that does not kill it.