"And there is no evidence that anyone "back then" created a large loop for a lever action."
The first use of a "speed ring" (large lever hoop) was in the movie
Stagecoach.
Director John Ford wanted something unique for Ringo to do for his opening scene. It was suggested to John Wayne that he figure out "something to do" with a revolver that would be unique for his opening appearance in the movie.
John Wayne was at a bit of a loss as to what could be done with a pistol that was new and unique for the shot and decided to talk it over with Yakima Canutt the stunt coordinator.
Yakima Canutt said that one of the most amazing things he had seen as a child was a guy in a wild west show who cocked a lever action rifle with one hand and repeatedly shot it. He asked if John Wayne thought he could do that? Wayne tried it with a standard lever action, and because his hands were so big he could not get the gun to rotate around his hand as needed.
So, John Wayne and Yakima Canutt went to the prop master and asked him to modify a rifle so it could be cocked one handed - showing him the problem with the standard rifle lever.
After some trial and error, the large lever hoop was developed so that the rifle could be cocked one handed. Then it turned out the barrel was too long to easily work the gun, so the barrel was shortened - and that's the first appearance of a large lever hoop lever action rifle in the movies - John Wayne's opening shot in
Stagecoach.
It became one of John Wayne's trademark guns that he used consistently throughout his western movie career.
Whether anyone actually used a rifle modified like that outside of a wild west show or the movies is unknown - but, it's certainly possible.