Can you fire a 9mm luger in a 380?

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.......................