I don't know anything about old guns. I bought a model 1917 Colt .45ACP revolver (manufactured 1917 or 1918) and fired about 100 rounds through it of PMC Bronze 230gr, velocity 830 fps. There is now a bulge in the barrel close to where it joins the frame and a longitudinally oriented, shallow crack. Is this surprising? Did I do anything wrong? Could a replacement barrel be fitted at reasonable cost?