Your firearm is out of time, the cylinder hand or even the ratchets on the cylinder are worn, As stated, these old Spanish " Ruby" revolvers are made from soft iron, not steel.The 32-20, even loaded down as the modern is, is still a hot pistol round. now this is your firearm, you can do as you see fit, however if you continual to shoot it you are responsible for your own injuries and for those around you when it gos boom. If your lucky it will only break instead.
Buy the way your grandfather may have acquired the firearm while in service but he did not receive it as per issued. The Army has been known to do some very foolish tings, issuing Spanish Ruby revolvers is not one of them