If the barrel is thick enough and it's a small caliber change to a larger size, it can be done. But it requires specialized barrel milling machinery, and the quality will never be as good as the original caliber it was designed for. Also; you would need to install a different chamber that would handle the larger round, as well as a new magazine. All in all, you're better off just to buy a new gun in the caliber you want.
It will usually be marked somewhere on the barrel.
Depends on the caliber, barrel length, projectile weight.
It should be marked on the barrel.
What is the caliber, barrel length, finish, grip material, markings on barrel?
Caliber is the size of the barrel's inside diameter, in fractions of an inch. A .25 caliber pistol fires a bullet that is about 0.25 inches across. Pistol can range from very small (about 10 caliber) up to very large (75 caliber) and there are hundreds of different cartridge sizes in between.
ABOUT $150, depending on condition.
4 inches including chamber.
Need to know caliber, barrel length and whether it is a revolver or semi-auto pistol in order to answer.
Turn of the century
suggest you check writting on barrel. it should indicate caliber..............
One can make a pistol much larger than it needs to be, maybe even having an extra-long barrel would make a pistol larger, technically. I'll assume you mean the barrel diameter. Although it would seem that a .380 and .38 would have the same barrel diameter, namely, 38/100th of an inch, that is not usually very accurate. The .380 ACP has an actual barrel diameter of about .35 caliber, or 35/100th of an inch. The .38 Special has a barrel diameter of .357 caliber, or 35.7/100th of an inch. So the .38 Special has an ever so slightly larger diameter.
Need model number or style. Most likely this is an FN gun in the Hi-Power line of 9mm. The barrel should tell you the caliber.