The acronym on McCree’s belt has stumped me and many others.
But I think I’ve figured it out.
It’s a reference to the Lone Ranger’s iconic catchphrase.
From Wikipedia:
The fictional story line maintains that a patrol of six Texas Rangers is massacred, with only one member surviving. The “lone” survivor thereafter disguises himself with a black mask and travels with Tonto throughout Texas and the American West to assist those challenged by the lawless elements. A silver mine supplies The Lone Ranger with the name of his horse as well as the funds required to finance his wandering lifestyle and the raw material for his signature bullets. At the end of most episodes, after the Lone Ranger and Tonto leave, someone asks the sheriff or other person of authority who the masked man was. The person then responds that it was the Lone Ranger, who is then heard yelling “Hi-Yo Silver, away!” as he and Tonto ride away on their horses.
The skin is called Masked Man. He has a Texas Ranger star on his poncho.
Hi-Yo Silver, away.
I feel like an idiot for not figuring this out sooner, but in my defense, I thought the phrase was “Hi-Ho Silver, away” so you can see why it wasn’t my first guess.