Accuracy Problems With M1917

[Andrew1995]

I Finally got my hands on a Eddystone M1917 for $500 it in great condition 4 grove HS barrel the rifling seems to be in good condition with maybe very slight pitting (if any) and has been counter-bored. IDK if that really affect the accuracy but my question is i recently took it to the range and was not pleased with the accuracy i got 13 out of 15 shot on target mostly high right at 50 yard.. I was shooting 150gr surplus and some what i think were 150gr soft points that i had on hand..Ive hear that it better to shoot heaver bullet out of it because of the 1 in 10 twist of the barrel...but i really don't know has anyone had a problem like this or know what to do? Any help would be nice..

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[jamie5070]

How did you have the rear sight positioned? The down, battle sight position sights the rifle in at 400 yds +. With the staff up and the slider all the way down you will be closer to 100 yds. I'm not sure how the counter boring will affect the accuracy, but I would check for barrel/stock contact and looseness. Is the stock slightly warped or putting pressure on one side of the barrel? Ideally the barrel should free float except at the upper band where there should be a slight amount of upward pressure on it by the tip of the stock. Are the mounting bolts tight? Is the front sight centered in the base? I would check these things and then head to the range again.
john

[Patrick Chadwick]

I think that one day I should get around to making a properly thought-out decision tree for this, but here goes with a first approximation... Updates and corrections are to be expected!

Precondition: make the usual checks of the rifle for head clearance, damage-free crown, barrel fit in channel, plausibly tightened system screws etc. These have been described several times in these forums.

1) Pick a range, preferably 50 meters/yards for a very first trial, since you have no idea of the relationship between POA and POI and want to be reasonably sure that the shots will be on the paper!

2) Take some standard 30-06 commercial ammo, nothing exotic. On an M1917, put up the backsight leaf and set the slider as low as it will go. Shoot off a sandsack or good rest, and use a 6 o'clock aim. This will put the shots on target in a typical 8" black at 50-100 yards/meters. Shoot five shots.

3) Are all bullets on paper? At this stage, it does not matter where!
YES – go to 4)
NO - the rifle has a defect. Not an "issue". A defect. Go to 6)

4) Are the bullet holes round?
YES – go to 7)
NO - this indicates keyholing or marginal bullet stability. But some bullets take a short distance to stabilize. If the POI is central enough to permit it, increase range to 100 and try again.

5) Are the holes round now?
YES - it was the bullets taking a while to stabilize. Go to 7)
NO - You have a problem. Go to 6)

6) The cause could one or more of
a) Seriously worn throat
HELP: reloads with the thickest flat-base bullets that will chamber, set out as long as they will go.
b) Damaged or bell-mouthed muzzle and/or crown.
HELP: recrown worn/damaged crown. Counter-bore worn muzzle (already doen in this example).
c) Bullet diameter too small for rifling – since you are using commercial 30-06 ammo, the rifling must be seriously worn.
HELP: reloads with the thickest flat-base bullet that will chamber.
d) Bent (i.e. damaged) barrel or barrel being bent by hard bearing on the barrel channel (warped stock)
HELP: Straighten barrel. Ensure correct fit and/or float of barrel in channel. Correct or replace stock.
- All of the above must be fixed or at least mitigated before it makes sense to continue to 7)

7) Do you have what may be called a group at 50?
a) Diameter 3” or more. Not good enough. Return to 6) and check carefully.
b) Less than 3”. Not brilliant, but usable. Go to 8)
c) Less than 2”. What I would expect from an M1917 before optimization. Go to 8)

8) Horizontal POI
Is the group within the black at 50%.
NO: Go to 6) d)
YES: Drift the foresight blade (if required) to correct the horizontal position.
If the correction puts the blade more than 1/16” from the center line, then you may still have a slight problem under 6). Go to 6) and repeat
If the correction requires less than 1/16”, go to 9)

9) Vertical POI
After any necessary correction as under 8), the group should be entirely within the black at 50. But only if you are using the sighting and aim as in 2).
Group is now in the black?
YES – go to 10)
ABOVE – the foresight blade may be too short. Replace with a higher blade. Go to 2)
TIP: Lee Enfield blades fit!
BELOW – I have never experienced this with a military rifle. A bent barrel is a possible explanation.

10) You have a rifle that groups sensibly on target at 50.
Go to 100 and repeat!


Note: The above may seem complex, but if you perform all the steps in sequence and carefully, you will reach 10) much faster than if you just dive in and plink away!


Good luck with your rifle!

[Andrew1995]

I tried it in both the up and down... As far as the stock goes i cant get the barrel and action out.. Its a Remington stock so i don't know if its just a really tight fit or im just doing something wrong...I know you take out the screws and there's one going through the Upper band (where the bayonet stud is) but the stock just seems to be stuck there and can pull it lose. So i really cant inspect the stock and barrel.. When i put the screws back on i do tighten them down pretty well. When i got the rifle the sight was drifted to the left so before i took it shooting i drifted it back to center. After shooting i looked at the target and saw everything was hitting high right.

[Andrew1995]

Here are some pictures i took of the target and of the bore... The target was shot at 50 yard bench resting.. I did fire two shot at this same target at 25 yard to see if that would help at all. I circled 3 holes with a red marker, i believe two of them were the ones shot at 25, as for witch 2 i really dont know. Attachment 61217Attachment 61218Attachment 61219Attachment 61220

[browningautorifle]

I've sure shot barrels that were a lot worse than that one. The bullet holes do look a bit less than perfect to me, as in a bit of yaw.

[Andrew1995]

i appreciate the input would you think a heavier bullet would help?

[browningautorifle]

If it's not stabilizing I would go 150 spitzer... You said you used 150s but what profile. Heavier will be longer and that can cause a yaw. Thing is, you should be able to shoot the original factory weight or there's a problem. Wish I was a bit closer, we'd load a few different things and figure it out. I'd even try 130 spitzers if I could...

[Andrew1995]

I shot surplus 150gr flat base FMJs and 150gr SP which has some deformation on the point. from what i gather originally the barrels were meant for like 180gr and up and shooting lighter bullets would over stabilize. I would like to start reloading 30-06 for this and my garand but i dont want waist money on bullets that don't work well in this rifle or a gun that has a bigger problem.

[browningautorifle]

Yes, the earlier bullets were heavier but that changed. Don't know where this over stabilize thing came from, the wouldn't wobble like that though. Only thing to set your mind at ease would be go the other way and try some, say, 180s or 190s...and see. Unless the bore is more worn than we can tell and they aren't getting traction. Can't tell from here...