View Full Version : TDC/Timing: shaving the barrel shoulder

Mfg Eng
October 25, 2000, 13:18
OK I'm a little slow, but I finally barreled my receiver. In order to save trips to the machine shop I calculated how much material to remove to time it properly. Hand tight it came to 10 o'clock. Torquing brought it to ~11 o'clock. The thread pitch is .0625, or one thread every 1/16 of an inch. I needed to remove 1/12 of this (hours on a clock face), so 1/16 * 1/12 = .0052 inches per hour on the clock. It worked! I chucked the barrel in a lathe, touched the tool on the face, set "zero", moved .005 and cut the shoulder. It timed perfectly first try.

[ August 12, 2001: Message edited by: EMDII ]

October 25, 2000, 13:28
That's a sight better than my technique: eyeball it, take off one or two RCH of metal, four-star torque to 12:00.


Blood of Tyrants
October 25, 2000, 15:59
What is wrong with the RCH method?

October 25, 2000, 16:12
Well, my fiance's a brunette, so procuring a complete set of "gauges" could get me in trouble. I suppose there's a conversion factor, but when I have access to gauges gunsmithing is far from my mind.


October 26, 2000, 00:36
I'm with Byron on this, take to much off then
over time, swear a few good ones, remove,
smash with hammer a couple of times, bugger
up threads, more swearing, retorque, awh, just right.

RCH, hahaha, haven't heard that one for awhile.


August 11, 2001, 22:19
moved to FAQ