I have recently been bitten by the 99 bug and have found the forum a wealth of information. Thanks for sharing.
I started with a 1955 99F 300 quickly followed by a 1949 EG 250 and I am now waiting for a 1919 1899 250-3000 takedown to arrive.
I am already looking at a 99A in 30-30 which has a sling swivel on the barrel which I have only seen one other time on a YouTube video by USOG.
I can’t tell if is part of the barrel or not.
I have hunting and predator control to keep them all gainfully employed on the farm in Ontario Canada.