Actually it's the reverse, but the same. The .44 caliber M.1860 was the same frame as the M.1851 "Navy" in .36. The only difference in the two was the rebated milling of the .44 to fit the larger cylinder front. It was improvements in steel manufacturing that allowed Colt to make a lighter weight Dragoon, if you will. But to answer your actual question, it should be possible to make a standard looking M.1860 out of the so called .44 Navy by swapping out barrels. Of course, you'd have an incorrect brass framed version unless you used the steel frame version and the grip would be shorter unless you swapped out the grip frame for the longer M.1860 style.