Tonight should be (I hope) the last of my M1A customizing, prior to live fire. I don't have enough time to go to the range, but I have enough to install goodies, if UPS and the mail cooperate.
Today they did, bringing me the following items:
First the always-handy bolt takedown tool for the M1 and M14.
What you see above it is a GI headspace test bolt for an M1. Used in conjunction with a go-nogo gauge, it will tell you whether the barrel-to-bolt face headspace is safe or not. The cuts (and the firing pin stub welded in place) are hints that this is not a "live" bolt, but rather a gauge.
Here it is in the tool, pretending to be a real bolt. Squeeze the handle and it pushes the bolt forward, compressing the extractor plunger. A button on the bottom then pushes up on the extractor stem, letting you remove it. Slowly release the handle, and the rest of the bolt innards come out.
I guess this is the place to confess that I once had a complete depot-level set of M14 inspection gauges, complete in their fitted wooden box, and an inventory label on the inside cover listing all the appropriate pages in the TM where they were discussed. I didn't have an M1A at the time, so I swapped them for some other toy. They're really of no use unless you're building something from the ground up, but they scored high on the coolness scale.
A similar nifty-but-probably-unneeded tool is the M1/M14 trigger assembly takedown tool.
Again, it provides the extra three hands needed to safely compress, remove, and reinstall some vey powerful springs in the trigger group. I cannot impress anyone (including myself) too much about the importance of wearing eye protection when working with any springs. It may be just some dinky spring, but it still could be strong enough to launch some tiny part right at your eye.
Now a couple of smaller items. On the left is a tool to grease the tiny roller on the end of the bolt that runs around in its little track in the operating rod handle. To the right of that is a plastic buffer that goes over the operating rod spring. It cushions the impact of the operating rod against the front of the receiver when weapon is fired. For $13 it's cheap insurance against battering, even if it only lasts a few thousand rounds.
Next, something a bit more exotic. On the left is the super high-tech National Match gas piston, with the regular ol' one on the right. These are the ones going into the military's new "born again" M14s. The piston is made of Austrian "boutique steel", probably N90. It's held to tighter tolerances than stock, and is given a TiN plating to help protect it, and provide smoother operation. It also has the new "National Match groove" down the front of the cylinder, running through the gas hole.
The critical dimensions on both parts are identical, as far as my digital caliper and micrometer tell me. But the standard piston slowly falls to the end of the cylinder when I turn the action muzzle-up, while the new one thunks right to the bottom of its stroke instantly. I think the old one is trying to overcome a partial vacuum during its fall, slowing it down. The groove on the new one must let in enough air to stop the braking effect. This is supposed to be good, although I haven't quite figured out why. But if it's good enough for us taxpayers to buy, it's good enough for me to get one, too.
Here's a quick look at the underside of the assembled action, showing the new piston on the left, and the recoil buffer on the right.
The most important item just arrived in the mail today, and I had just enough time to install it and take a picture before heading off to work. It's the adjustable cheekpiece, and all it required was the drilling of four holes in the stock which, if done correctly, joined up to form two 1/4 inches holes straight through the stock, and lined up properly.
I used a drill press, rather than trusting my eyes to do it freehand. Everything was laid out on masking tape placed on the stock, and then triple checked.
Fortunately, it worked. Everything is quite simple. Loosen the two thumb screws, and move the cheekpiece. In my case, things were so snug that I had to "persuade" the part with a rubber mallet, but that might be a good thing. Nothing is going to move until I whack it.
I used my dad's old rule for fitting guns: close your eyes, bring the weapon (unloaded, of course) to a natural firing position. Open your eyes. If the sight picture isn't perfect, readjust. It took me two sets of thumping with the mallet, but now the Aimpoint points right where I want it, and everything feels sooooo comfortable. The rifle now feels alive and responsive, and ready to do snap shooting out to quite a distance.
John C. Garand should be proud of his grandchild. After being put in the back of the armory for 40 years, it's now finding new life in civilian and military hands.