Obviously not a Python, which had that unique vented backstrap. It was definitely a model 629, but it was a 4 inch barrel, combined with that oversized wooden grip, made it look like a cannon. I carried a 2 1/2 inch model 19, which, when held, looks twice as big as its 4 inch barrel cousin. With the larger frame revolvers, the shorter barrels made it look "fat", hence more menacing. I also carried a S&W model 686 4 Inch, but that 2 1/2 inch model 19 was the sweetest shooting revolver I ever owned. (carried it in plain clothes assignments, both standard draw, and with the Trivett, Sonny Crockett shoulder holster.... ) In season 3, episode 8 & 9, Walker had his revolver shot out of his hand, which destroyed it. So Alex, Trivett, and CD pitched in and surprised him with a stainless Beretta 92, which he carried till the bitter end. Seasons 1 thru 6 were definitely the best. He got way to much into "causes", like kids and neighborhoods in the last few seasons instead of doing police work. I do admit though, the 2 new Rangers, Sydney and oh, what's his name, well, Sydney anyway was a breath of fresh air, she was so, umm, LIMBER..........I went to look at my favorite website for finding out what guns are used in TV and movies. Internet Movie Firearms Database - Guns in Movies, TV and Video Games
But unfortunately, it didn't answer your question due to incomplete data. A little more searching and I thought the answer was a Colt Python 357. But another site gave me this info.
Chuck Norris' 'Walker Texas Ranger' carried a 6-inch stainless Smith Model 629 .44 Mag in a cross draw holster in the first season. It was very similar to if not the same exact rig he used in the feature 'Lone Wolf Mcquade' that was incidentally the inspiration for the TV series. Norris later switched to either a stainless Taurus or Beretta 92.
I can sort of see how someone could mistake one for the other.