to the forum.
It looks to be a .38 Military & Police Change 4. It is a .38SW caliber NOT a .38 Special caliber. My guess it is either a British Service revolver or a Victory from the 1940's. Look on the bottom of the gun butt and see if there is a serial number; a six digit number possible with a V in front of the numbers. Looks like a 5" barrel. Yes, put lots of oil on it.
Here is one that I think was like yours. It was made in 1944.