Goofs

In the last scene Margaret uses a shotgun to shot and kill a man who tries to take her horse. Maragaret left her shotgun with Colton when she took his horse. Colton carries a rifle in his saddle holster, as seen numerous times earlier in the episode.

When the crew goes to ground to fight off the cattle thieves, Shea's rifle switches back from one with a full under-barrel magazine to one with a half-barrel magazine, and then back again.

In the horse race scene, a bit is visible on the horse that Sam was riding. In 1883 it would have been a war bridle, a rope loop around the lower jaw. The adoption of the traditional Western bridle came later.

@15:01. Margaret Dutton responds to a question by saying "to dream of indoor plumbing." Indoor plumbing does not enter the American mainstream lexicon until the early 1890's. Before that period indoor plumbing would have been extremely rare and found only in the most modern progressive cities like New York City or Chicago. Her home state of Tennessee would not have seen modern indoor plumbing until the turn of the 20th century, almost 20 years later. That doesn't mean that she was unaware of it, even if she had never seen it. Some have posted here that she would not know the term, but she certainly could.

When Elsa is coming back after the storm with the two horses, she runs into her father. Her father asks her where the two men are. She replies, "right behind me" and turns back. That seems to be a mistake on the part of the director.

At 20minutes and 35seconds you can see Elsa's tape in extensions. Which obviously didn't exist in that era.

After the rustlers are killed the 'team' doesn't round up the cattle to take back to the wagon train. Also, they would have taken the dead rustlers' horses, guns, and ammunition for their own use. There is no evidence of the cattle in the following episode that they needed for food.