Believe that Mulie shot is in one of his books. I read "Hell, I Was There!", his autobiography, a lot of years ago. Sort of remember it was in that one, check your local library, I know it's in ours. He stated he had a surveyor measure it for him. Being from Maine, I sort of went, HUH?? However, 18 years in Wyoming and it's more of "great shot"! I've watched a lot of guys "walk" their revolvers out to the 500 meter gong at the local shooting range. Can be done, which is basically what Elmer did. By his own admission, he hit it on the last shot. And as posted, he did excessive long shots a lot and was good at it.....Wish I Were There!
Regards,
Sweetwater