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View Full Version : Tuner,? about lugs


kart racer
August 24, 2007, 05:47 PM
Why are the back edges of the lugs on tanfoglios beveled?They have basically the hi power setup.Is it becuase of the cam design?The lockup on my examples are tight.Just wondered why they did it and 1911's didn't.

http://img167.imageshack.us/img167/9333/mvc003snv6.th.jpg (http://img167.imageshack.us/my.php?image=mvc003snv6.jpg)
http://img167.imageshack.us/img167/4610/mvc002sfu7.th.jpg (http://img167.imageshack.us/my.php?image=mvc002sfu7.jpg)

WESHOOT2
August 26, 2007, 07:06 AM
so flanging does not occur (which leads to wiring).

Unclenick
August 27, 2007, 05:29 PM
. . . which leads to wringing (of the hands).

K.R., it is a standard step in fitting up a 1911 to take a file or scraper and add beveling to a barrel's locking lugs edges. This guarantees smooth meshing of the barrel lugs with the slide lug recesses, and avoids the problems Weshoot2 mentions; peening of the lugs to create a wire edged flanges that can separate and/or cause jamming.

When you consider the angle of a 1911 barrel in lock-up, you realize that only one lug bottoms out in its recess in the slide and that the faces of the back edges of the barrel lugs don't meet the recess partitions squarely. They were made the way they were for practical compromises to do with machining processes available in 1911. If J.M.B. were alive today, I have to believe he'd have been all over the possibilities for CNC machining, and would have done it a bit differently in some details.