Grade8
Yes. There were conversions being made by various Gunsmiths. Most "early" conversions were .38s. .44 conversions were done, but initially were converted to use .44 Henry Flat. Later suplimented by .44 Stetson (The Open Top). Colt factory conversions after the death of the Bored Thru patent, were often converted to .44 Colt.
Now. When it comes to Hollyweird, anything goes. NEVER watch Hollywood, Bollywood, or Spaghetti Westerns looking for firearms period authenticity. You WILL be disappointed.
People ARE Hazardous to Yer Health