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Ithaca Gunner
06-06-2016, 12:45 PM
With much sadness I separated the original barrel from my M-1 Rifle yesterday. It had been on that rifle since early 1943 and gave good service until a few years ago when she started turning in 3" groups at 50yds with my favorite cast boolit load. I had the new Criterion G.I. contour barrel, pull through reamer, receiver wrench, and barrel blocks for my Brownell's barrel vice for a few years, but hated the thought of using them on my pet M-1.

Well, last week I made a "timing" gauge set out of 3/8 drill rod and decided this week-end would be the operation on my dear friend. I stripped it down to bare receiver and barrel, discovered some fine sand mixed with the cosmoline hiding under the rear sight base and wondered, "What beach did that come from?" An early just over one million sr. number could be a great many beaches, possibly multiple beaches. The original barrel turned right off with little force using a 3' pipe on the wrench. After examining it the thought went through my mind, "It's not that bad..." (yeah it is, the throat gauges over 8, almost a 9 with thin rifling present).


After chucking the new barrel up in the blocks and tightening the receiver I removed the front sight from the gas cylinder assy. and mounted it on the barrel, leveled the entire thing and put my high tech timing gauge to work passing one drill rod through the rear sight hole and leveling the other against the front sight dovetail. Getting down on my knees looking down the works I could see the rods were anything but parallel, the receiver needing a few degrees more turn on the barrel. A few more tiny turns on the receiver wrench and by-golly, it timed!

Time for reaming. I had to weld a "T" handle on the pull through reamer rod, but no biggie. Strip the bolt down to just the body, insert in the receiver, place the reamer in the chamber, thread on the rod on, apply a generous amount of cutting oil and I was ready to finish the chamber. Thumb pressure on the bolt following the reamer is all that's needed, (keep a close eye on that right side locking lug!) and soon the right lug dropped fully into place. Disconnect the reamer and pull it out, clean any chips from the chamber and head-space...Perfect!

On reassembly and zero sights I found my "high tech" timing gauge had worked very well! Brownell's wants over $75.00 for a timing gauge. It can be done with 2-3/8" drill rods, each 24" long and a small level for a whole lot less, (in my case the drill rod was even free). The front sight post stands perfectly straight in the rear appeture.

Now for some range time. I expect the 50 or so c.b. rounds I have loaded may shoot less than stellar since they're over size to compensate for the worn 1943 barrel, but I expect much better targets in the future.

country gent
06-06-2016, 01:00 PM
There are several ways of doing this, yours with the 3/8 rods. I have done it with 2 precission levels. and I have seen front "Gage" made with the bore and spines to be held on with the gas cylinder nut. The proof is in the shooting when pefectly timed the front sight is centered on the dovetail and the rear is mecanical zero for wind. The real pain comes when they wont time up and have to be faced or the shoulder expandered ( over center when tight). The above gage was used with a rod and tapered nuts to center rod in sight holes them placed on a surface plate rod was indicated in the gage to zero on both.

Der Gebirgsjager
06-06-2016, 03:40 PM
I do mine in a somewhat similar way. I put a machinist's parallel bar on top of the receiver flat behind the rear sight, and another level on a parallel bar on the front sight base with the blade removed. When everything reads level and the bars appear parallel to each other when viewed from the rear you're there.

Ithaca Gunner
06-11-2016, 02:42 PM
Well, the drill rod timing tool must be okay, I shot it today, only needed 3 clicks right from zero needed for windage.

M-Tecs
06-11-2016, 02:53 PM
I do mine in a somewhat similar way. I put a machinist's parallel bar on top of the receiver flat behind the rear sight, and another level on a parallel bar on the front sight base with the blade removed. When everything reads level and the bars appear parallel to each other when viewed from the rear you're there.

I have a pair of 24" rules that work great for this. I've only did a couple of Garand's but I've done 80 plus M14's without any issues.

The real test is not have a windage change from 200 yards to 1,000 yards.

M-Tecs
06-11-2016, 02:57 PM
Well, the drill rod timing tool must be okay, I shot it today, only needed 3 clicks right from zero needed for windage.

Normally you leave the rear sight at zero and move the front sight. I built a clamp with and indicator for this.

Ithaca Gunner
06-11-2016, 04:23 PM
Normally you leave the rear sight at zero and move the front sight. I built a clamp with and indicator for this.

I agree for that little bit of windage, and planned on doing the same, but I forgot my Allen wrench when I went to the range.