NEVER FIRE AMMUNITION IN A WEAPON IT IS NOT CHAMBERED FOR!!!!!!!!!!!!!!!!!
No, No, NO
No. Shoot only the caliber printed on the barrel.
No, the bullet will not seat.
Let's start by using the right term- I think you mean a .380 cartridge- many guns use .380 caliber BULLETS.In general, NO. Unlike .22 shorts and long rifles, rimless cases do not interchange. It may be possible to get a .380 cartridge to fire in another gun- but not safely. Use ammo that is the caliber marked on the gun.
9mm and .380 bullets are the same diameter. In fact, .380 is also called 9mm Kurz(short) or 9x17. However, the caliber commonly called 9mm is 9x19, which means the cases are different size. A .380 cartridge will fall down into the chamber and the firing pin will not reach the primer. So, a .380 bullet can be fired from a 9mm gun if it were loaded into a 9mm case. A .380 cartridge would fail to fire in a 9mm gun.
It depends on the model and the caliber of the Pellet gun.
Many makers offer firearms that shoot the 380 ACP.
No.
gun shows, gun shops, want ads
You can from some, but they have to be designed to shoot both.
No
Impossible to answer without knowing the caliber.
No, the calibers and chamberings are completely different. It is not safe to attempt to fire any caliber of ammunition in a gun, other than what is stated on the barrel. actually the 380 caliber is almost equal to the 9mm. the 380 caliber is often refered to as a 9mm short. the difference is the 9mm case is slightly bigger then the 380 case and the 380 bullet might be a little lighter.......................