Truing/ accurizing m1917

[SurplusPrecision]

Just bought a semi sporterized eddystone m1917. As a project for school (Colorado school of trades) I plan on restoring / accurizing it. Have acces to a machine shop and gaining the knowledge to use it. But I am looking for some tips/ recommendations on how to go about the process of making this rifle as accurate / precise as possible while keeping the rifle correct. I would appreciate any guidance.

[Patrick Chadwick]

...recommendations on how to go about the process of making this rifle as accurate / precise as possible while keeping the rifle correct...

That sounds a bit like "wash me, but don't make me wet".

"Correct" is usually taken to mean "according to the original ex-factory configuration". Accurizing is, by definition, a post-factory procedure. Which contradicts the idea of "correct".

So you have to make a compromise. What are you prepared to do, before it jars too extremely with whatever you find to be correct? No need to get in too much of a theoretical sweat, I think. A rifle that has been sporterized has lost it's originality anyway. You can restore it to the original configuration, but you can't make it original again.

If you want to accurize an M1917, all you really need to do is to bed the receiver/action body and let the barrel vibrate freely. Make sure that the trigger action is smooth, but don't start grinding down the sear/cocking notch engagement*, just polish it. And then check that the muzzle is perfectly clean and symmetrical - many old milsurps suffer from maltreatment and cord wear around the muzzle. A tiny touch with a crowning tool - just enough to get a bright ring all the way round - is IMHO a legitimate maintenance action.

If you then carry out the procedure to find the optimum load that I described here once upon a time (you'll have to search for it yourself) then your Eddy will be as good as any military rifle can be. About 2-3 MOA on a good day with service sights off a sandsack, maybe 1 MOA with a scope.


*This is one area where the old machinist's motto "you can file it off, but it's difficult to file it back on again" applies in spades.

[SurplusPrecision]

I certainly understand that there will be a compromise made between having the rifle completely correct and as accurate as I would like. I suppose that "correct was the wrong term, but a better way to explain it would be similar to resto-mod. This project is mainly just me imagining what someone modifying the m1917 into a sniper rifle if they had access to some of our modern day tech ( barrels, optics, trigger) while retaining the original stock and sights with a preferably period style optic mount.

Current plan is to replace the stock with a repro from either numrich or liberty tree collectors. Then replace the barrel with a criterion piece or a blank in a non standard m1917 contour ( light palma, medium palma are currently what I would be leaning towards, around 28-30"). I'd also eventually like to add an accumount p14 scope mount, in addition to a timney trigger. As far as accuracy is concerned I was wondering if there would be any benefit from truing the receiver face, lapping bolt lugs, etc.

When you say allow the barrel to freely vibrate, do you happen to mean free floating the barrel or a shim system as I've read about here on the forum?

While it has been sporterized, the person who did it simply cut off the stock in front of the lower band, leaving the original barrel and both sights in place. The rifle was made in November of 1918 according to the barrel and serial number.

I appreciate your input!

[Daan Kemp]

Why not get the most accurate load first, you might have sniper accuracy right now. Once you have the most accurate load, fiddle with bedding, free floating, etc, until it improves more. Then look at other options.

If you want to build a sniper rifle why not start with a complete action only and go from there? As you want to replace the stock, trigger, barrel, etc, in any case.

[Patrick Chadwick]

My Eddy is also Nov. 1918, and has been treated as I described, so I am not writing theoretical waffle.

The barrel should be free-floating from the nocksform onwards. No funny business with shims, cork, phases of the moon etc.

And if I can find the target shot with a scope mounted, I'll post it here.

BTW, how about a photo or two? If your Eddy has the original un-Bubba-ed barrelled action and sights, then IMHO it is worth finding an original stock + barrel bands to refurbish it.

[Patrick Chadwick]

Made at 100 meters, off a sandsack, service sights



Note that it is statistically awkward to define the best. But easy to see the worst: loads that should be avoided.

Note also that, as the group size variation is almost certainly a resonance effect of the barrel whipping around, it will vary according to powder type, bullet form, weight, seating etc. In other words, you will have to determine it yourself, for your rifle.

[Patrick Chadwick]

Now I found the scope test!



This was made with my Eddy, using factory ammo. Free-floated barrel, bedded receiver and nocksform.
The scope mounting was one of those slightly flaky wedge-action types, fixed in place of the backsight, so as not to drill and tap the action.

As you can see, it has sub-MOA potential - 2 scope sighters and 3 out of 5 in the group almost form 1 hole. For the two other shots I have no explanation other than my PWF! A permanent scope mounting might provide better results, but I don't like making irreversible alterations to antique items.

[Patrick Chadwick]

Current plan is to replace the stock with a repro from either numrich or liberty tree collectors. Then replace the barrel with a criterion piece or a blank in a non standard m1917 contour ( light palma, medium palma are currently what I would be leaning towards, around 28-30"). I'd also eventually like to add an accumount p14 scope mount, in addition to a timney trigger. As far as accuracy is concerned I was wondering if there would be any benefit from truing the receiver face, lapping bolt lugs, etc.

If you do all that, IMHO you are reducing an original barrelled action that only needs a replacement military stock to a DIY rifle that has nothing left of the original apart from the action.

I seriously advise against that course of action, and hope that my posts have demonstrated that you can achieve sniper quality without it.


"As far as accuracy is concerned I was wondering if there would be any benefit from truing the receiver face, lapping bolt lugs, etc."

OMG NO! NO! Unless you are such an expert gunsmith that you wouldn't need to consult this forum in the first place, that is a sure-fire way to ruin the rifle by spoiling hardened surfaces.

[Sunray]

Before you do anything, you need to do an inspection of the barrel. I'd slug it and look very closely at the rifling. No point fiddling with a rifle with a poor barrel.
Restoring any milsurp has gotten really expensive. It's mostly about all the wee metal bits. Gunparts, for example, wants $5.50US each for a large butt plate screw. $12.50 for the lower band assembly(front sling swivel to the rest of us). $207.50USD for a new walnut repro stock with no metal. $32.75 to $40.75 for a new lower hand guard and $26.00 for the other one. Nearly $300 before shipping and all the metal bits. They do not have any original surplus stocks. And a lot of the wee, tiny, metal bits(screws and such) they don't have at all.
However, since your current plan is to build another sporter on the 100 year old action, don't even think about a military style stock and all the wee metal bits. No need to inspect or slug the current barrel if you're going to change it anyway. You will not be keeping it remotely "correct" with your 'current plan' though. Not a big deal though. It has no collector value anyway.
"...barrel should be free-floating..." Floating a barrel guarantees absolutely nothing. Some rifles like it. Some do not.

[us019255]

" Floating a barrel guarantees absolutely nothing. Some rifles like it. Some do not.

Back in the '80's I rebuilt a 1903A3, and a M1917. Both had come back from some Arabic country per the writing on the butt stock. The barrels looked like they had fired ~5K rounds of corrosive ammo between cleanings. I replaced both barrels with new old stock WWII replacement barrels. Per usual instruction for "accurizing" I free floated the barrels and glass bedded the action. No joy. I then used glass resin to put 5 lb. of upward pressure on the muzzle. Bingo, they then shot well (~4" groups at 200 yds with stock sights, and my poor marksmanship), and no change in elevation with warming.
JMHO, your results may vary.