Possibly they were
Thanks to M D Christian for the following:
"This was submitted to
Handloader Magazine, Jul/Aug 1970 by Harvey A Donaldson who said it was told to him by Frank Lefever, son of D.M. Lefever. He stated this was the method used in finishing stocks by Dan Lefever and other U.S. gunmakers and gunsmiths including Billinghurst, Brockway, Morgan James, and A.O. Zischang."
1.
Place the stock in a sheet iron tank with enough linseed oil to cover stock. Stock was left for a day or so depending upon density of the walnut, a harder denser grain wood requiring longer than a more porous grain wood. Next was to remove the stock & stand to drain & leave for several days at least. Very Important: let stock dry completely; this first coat must be completely oxidized by the air before proceeding.
The rest of the process is about 2/3 down here under "Maintenance and Restoration"
http://lcsca.clubexpress.com/content.aspx?page_id=274&club_id=43784&sl=858381813 
