Don't fret. You are in the right forum and, if not, the friendly moderators will move your post to the correct forum with a smile.
Your grandpa had great taste in firearms. You have one of about 9000 .38/44 HD Transitionals made. I recommend going to
https://38-44heavyduty.com and sending the forum owner your serial for his database. When S&W started using model numbers in 1957, your HD would become the Model 20. Of course, by then the action was changed out from the long throw hammer to the short throw. As you apparently have already found out, they are great shooting guns with extremely manageable recoil. I love target grips on these guns but they may be a bit big for your hands. Enjoy!