It's really going to depend on the gun. Feeding might be a problem. However, I believe you will probably be able to work out the problems by adjusting the OAL (overall length) of the cartridge. My recommendation is that you find some round nose bullets of a good weight for the .380. Then make small batches of ammo, adjusting the OAL until you get reliable functioning. The pressures will be lower than the same load firing a jacketed bullet.