The 1895 Montgomery Ward catalog mentions "Lefever Taper Boring" http://books.google.com/books?id=zWel51IwQ2AC&pg=PA450&lpg
When was that term first used by Lefever? An old thread describes a 4" choke taper for full choke
http://www.doublegunshop.com/forums/ubbt...&PHPSESSID=

Last edited by Drew Hause; 05/02/12 05:24 PM.