Hello Out There,
I am a first time visitor on this forum. I have a professionally 1/8" machine lathe relieved .303 Enfield P14 barrel, as similarly listed on gunpartscorp.com as product #532590, and I am trying to determine whether or not this barrel is considered to still be in shootable condition. The machine lathe work looks to have been professionally done in preparation for the barrel's removal from the receiver of it's original receiver host, as the machined relief is only about 1/8" wide and no deeper than the depth of the threads. Any assistance from anyone having restored a drilled P-14 rifle in this regard would be much appreciated.
Let's see if we are on the same page........Some barrels on military rifles are set with a high torque.......the profile of the exterior of the barrel is that a threaded shank is cut and a shoulder created on the barrel...that shoulder bears on the face of the receiver...setting headspace in the process.........Military barrels will not rotate up to top dead center......the 2 surfaces will touch by and snug up as much as a half turn from clocking the barrel(brings sights cuts etc to TDC)........and some will use a thread sealer(similar to Loctite).....if there comes a time where a depot or dealer wants to take barrels off...using the standard barrel vise and action wrench can be time consuming and tiring work...add it...that may military barrels suffer dame. They start out with excessive headspace and then combat does them no favors...shot overheated....with corrosive ammo etc...seldom properly cleaned...One thechnique used to deal with corrosive ammo is to neutralize it with human urine.....So to quickly remove the barrels...a lathe cut was made on the barrel...moving the shoulder forward and releasing the torque
Genarally speaking...such barrels are a poor choice for a rebuild......You would have to recut the shank and thread it...and then re cut the chamber......since you are dealing with operating pressures around 55,000 PSI...things have to be exact......In some low pressure chamberings...such a cut is dealt with by making up a ring bushing to fill the gap created by the lathe cut......In a nutshell...the amount of work and the time spent makes the price of a proper barrel cost effective......BTW...you should also look at your barrel to see WHY it was being removed.....is it bent?...did it get run over by a tank?;;;;;;;is the bore rusted out?
If it is a DP barrel with the hole drilled through the chamber throw it away.If it has a good chamber and bore you can make a steel sleeve to replace the 1/8" of material removed from the barrel.In the old days some 45/50 years ago when barrels were hard to find I made a few this way.It has to be perfect so the barrel will tighten up properly and index correctly.In the old days gunsmith's would make a releif cut so the barrel could be unscrewed by hand.No gunsmith today would ever consider such a thing unless the barrel was total garbage.
There are some technical articles on whether clocking a barrel has a positive affect on accuracy...Basically...the should of the barrel is cut back and there are no extracter notches cut...fired cases are hand picked out......Basiacally a series of steel washers...of different thicknesses are used between the receiver to deal with the rotation of the barrel as it is screwed in...I think what they are doing is postioning the rifling........
The only reference I have to it is inPrecision Shooting Magazine...the Sept 2007 issue An experiment in barrel indexing,,,,,,,Chapter one.......by Bill Calfee........You should be able to pull up the article on line.....