M1917 issues or did I just overcompensate?

[mdoerner]

Hi All,

Went to the CMP match at the Youngstown Rifle and Pistol Club today. I brought my "new to me" M1917 Eddystone. I've only put about 20 rounds through it at 75 yards just to get it "centered". Anyhoo here's how my day started.

At 200 yrds, slowfire, standing, 10 rounds, elevation at 300 yards on the ladder so I can use a 6 o'clock hold.....http://members.cox.net/mdoerner1/01-17-10_1052.jpg

....not bad IMHO for the 1st time out. I think I'm a little low, so I bump the ladder up to 400 yards, maintaining the 6 o'clock hold. I don't want to go up too much further as I know in the sitting and prone positions I go higher with my shots because my face is closer to the rear sight.

200 yards, sitting rapidfire....
http://members.cox.net/mdoerner1/01-17-10_1111.jpg
....WTF??!??! 1/2 in the back, 1/2 almost off the target? OK, so something happened at the reload. No biggie, I just won't do that again. Left my sights alone.....

300 yard reduced for 200 yards, prone rapidfire.....
http://members.cox.net/mdoerner1/01-17-10_1130.jpg
...dang! LOW AGAIN! Bump the ladder up to 500 yards for slowfire.

Now the weather conditions very fog/hazy and no wind. I shot most of my 20-shot string before I even saw any of these shots go high. It BOGGLES MY MIND that I didn't see any of these holes while I was shooting, but as soon as the smoke cleared a bit, my jaw dropped.....(yes, I need a better scope apparently)
http://members.cox.net/mdoerner1/01-17-10_1209.jpg
...the phrase WTF comes to mind. 1st I'm low, then I'm high and off the target. I compensate by adjusting my last few shots for 200 yards, but those are the low ones under the target.

Did I overcompensate vertically with the rear sight on my M1917? (I'm thinking so) Or does any of this indicate a wandering zero because of the barrel heating up? Should the M1917 be free-floated or have a pressure pad along the barrel?

PS The load I used was .30-06, 168 grn Sierra Matchkings, HXP case, WLR primer, and 44.0 grains of Accurate Arms A2015 (I'm really liking SOME of the results[ESP Sitting Rapidfire]. Looks fairly consistent.)

Any advice (besides bringing my Garand next time) would be apprecaited....

Mike Doerner

[Parashooter]

Assuming you're normally a decent shot, there's something wrong with your rifle or ammunition. One suggestion is to try flat-base bullets. The 5-groove original "Enfield" rifling often performs better with more bearing surface. If you need boat-tails, try the .3105" Hornadys, a better fit in the usual .300"X.310" M1917 barrel.

Looking at your targets, however, it looks like you have serious problems resuming your position after the reload and simply weren't holding very well that day. Nearly any decent M1917 can keep them all in the SR 10-ring at 200 yards, even with M2 ball ammo, if you do your part.

Other things to check -
Action screws tight?
Barrel clear of handguard and upper band?
5-10 pounds pressure at the forestock tip? (Should not be free-floated.)
Too thick handguard pulling up on handguard ring?
Trigger set up for clean 2nd stage?
Minimum legal trigger weight?

[mdoerner]

Assuming you're normally a decent shot,
That IS debatable. My best is only a 395-0X out of (500-50X), so there's lots of room for improvement.


there's something wrong with your rifle or ammunition. One suggestion is to try flat-base bullets. The 5-groove original "Enfield" rifling often performs better with more bearing surface. If you need boat-tails, try the .3105" Hornadys, a better fit in the usual .300"X.310" M1917 barrel.

I don't think the issue of flat base vs. boat tail is an issue here. I got excellent groupings in the sitting position (which is usually my worst position). Vertical stringing is usually breathing or worse, flinch related (and I think I've got a flinch. It's getting better, I believe)



Looking at your targets, however, it looks like you have serious problems resuming your position after the reload and simply weren't holding very well that day. Nearly any decent M1917 can keep them all in the SR 10-ring at 200 yards, even with M2 ball ammo, if you do your part.

Yes, I've been struggling with high power, but the biggest disappointment today was that a.) I completely missed the target on the "easiest" stage of the competition and b.) because of the haze/fog I didn't see the holes were above the target. I assumed they were in the black. I made an effort to ensure I was locked into the rifle correctly today, but that evidently didn't show up in the results......



Other things to check -
Action screws tight? YES
Barrel clear of handguard and upper band? Not certain, I will check. If not, how do you change/adjust the metal clips in the handguard for more clearance?
5-10 pounds pressure at the forestock tip? (Should not be free-floated.) Uncertain, how do you check this?
Too thick handguard pulling up on handguard ring? Possible, how do you check and correct this?
Trigger set up for clean 2nd stage? Yes
Minimum legal trigger weight?I will need to check, but seems similar to my Garands


I know it's hard to "critique" my problem since I have many issues, but I've never seen a "jump" in the POI like that, especially from prone rapid to prone slowfire. I will check the gun, but most likely, I'm thinking I must have jumped some of the notches on the sight when I started the last stage, and not being able to see where the holes were being punched led me to believe I was in the black.

Mike D

[John Kepler]

I know it's hard to "critique" my problem since I have many issues, but I've never seen a "jump" in the POI like that,
Mike D

Oh I have! So have plenty of others! You are using the "ladder", the light was funky, and let me guess....you're on the "downside" of 40!

POI shifts like that indicate that YOU were moving around on the rifle....a lack of an adequate and consistent "spot-weld" on the rifle. The use of the "ladder" has you "higher" on the rifle than normal, the light was funky, so "older eyes" go looking for a place to see...and the body follows, breaking the spot-weld on the stock, and shifting the POI. Add in running the bolt and likely having it breaking the spot-weld even more thoroughly, and you can go from blowing things out the bottom and then chasing them right out the top!. It's one of the larger "stupid pet tricks" that happens when one of us Old Farts shifts from a big old .30 cal to a MUCH shorter sight-radius....far less forgiving of spot-weld defects AR! It's fairly obvious that you've managed to develop one in your bolt-gun!

This is an issue that you can address with dry-fire practice in funky light at home!

[High Plaines Doug r]

Another thing you might want to consider in your mix is keeping your focus on the front sight. As John K noted as one gets older, the front sight becomes more of a challenge to focus on. When I tire in a slow fire string, or break concentration to change mags in a rapid, my focus looks for something it can see clearly. That turns out to be the target unless I really grit my teeth and remember the effect of not keeping my focus on the front sight.
Your sitting rapid target looks to me like a classic breakdown in position due to a mag change.
HTH

[mdoerner]

I really made certain with the M1917 front sight that I was focused on the FRONT sight the entire match, knowing full well that thin blade made for an excellent sight in the right conditions, I probibly didn't even think cheeck-weld. Also, I may have had my siling TOO tight, as in order to get into position I iad to put the palm of my hand on the butt, shove it forward, and then into my shoulder. I'm now remembering that I SHIFTED POSITION once or twice because I couldn't see though the sights properly.

Before I take the rifle out again, I will dry fire in "the dark" so-to-speak, but letting up on the sling one notch might help as well. I liked a tight sling, but not to the extent of losing points.

Thanks guys.

Mike D

[mdoerner]

Oh I have! So have plenty of others! You are using the "ladder", the light was funky, and let me guess....you're on the "downside" of 40!

Actually, 37....but with the eyes of a bat!:icon_lol:

Too bad I can't use a "radar" sight....

Mike D

[CMP Shooter]

Looks like a lot of things going on, but yeah, I think you overcompensated with the vertical adjustments. The two positions where you were most likely to have consistent holds were your offhand and slow prone targets. In looking at your offhand, I'd say your POI was just south of the black. You added one click up (at 100 yds., one click on my 1917's moves the POI approx. 8 inches), which effectively should've moved your POI 16 inches at 200 yds. You then added another click, so by the time you were in the slow prone position, you've moved your POI approx. 32 inches upwards, which seems to roughly correspond to your first shots in that position. Additionally, other commentors pointed out you're probably changing your position on the rifle. I also suspect you might have had a flinch based on your slow prone target. If it was easy, anyone could do it. The 1917 is my least favorite rifle to operate in the rapids as closing the bolt isn't easy, and I too have difficulty maintaining position with the darned thing (I like my '03's much better). Then there were the foggy conditions adding to the degree of difficulty. Lots to think about for sure.

[Bob S]

The "value" of sight changes with the existing ladder:

The sight radius with the ladder up is 31-5/8", so the value of sight change that equates to one MOA is .0092". (sight radius x TAN (1/60))


200 to 300: 2.6 MOA
300 to 400: 4.1 MOA
400 to 500: 3.9 MOA
500 to 600: 4.6 MOA
600 to 700: 5.8 MOA
700 to 800: 6.3 MOA
800 to 900: 7.6 MOA
900 to 1000: 8.4 MOA
1000 to 1100: 9.3 MOA
1100 to 1200: 11.1 MOA
1200 to 1300: 11.7 MOA
1300 to 1400: 12.7 MOA
1400 to 1500: 14.1 MOA
1500 to 1600: 15.3 MOA

The changes in the mid-and longer ranges will probably be of interest only to those who shoot mild cast bullet loads. We usually have to work in the 700 to 1000 yard settings on as-issued military sights when we are shooting at 100 or 200 yards.

My front sight adjuster is British, and the screws are 22 TPI. One full turn moves the sight 1/22 inch, or .0455". Using the .0092" per MOA, one full turn of the screw is worth 4.94 MOA, so figure 5 MOA per full turn, 2-1/2 MOA per half turn; 1-1/4 MOA per quarter turn. It can be used with one hand, so you can stay in position and in the sling to get centered up during the sighting period. After that, just take favors if need be.

If you're going to shoot it in NRA matches, a Parker-Hale No. 5B backsight is highly recommended. It clamps the side of the receiver using the ejector/bolt stop box spring and is stabilized by the existing axis screw: no modifications to the rifle.

http://img.photobucket.com/albums/v76/BobS1/M1917/PH5BBaseInstalled.jpg


http://img.photobucket.com/albums/v76/BobS1/M1917/PH5BBaseInstalledrearwithaxisscrew.jpg

http://img.photobucket.com/albums/v76/BobS1/M1917/PH5BGallowsArminserted.jpg

The hardest thing about shooting the M1917 is keeping a stock weld. If need be, tape multiple thincknesses of cardboard to the comb to build it up. Butt-ugly, but it works. I saw this done on several rifles at the 1992 Palma match!

Resp'y,
Bob S>

[mdoerner]

I also suspect you might have had a flinch based on your slow prone target.

Is that because of the "sideways" dispersion of the target or just the lack of a "group". Thanks.

Mike D

[CMP Shooter]

Mdoerner,
Yes, I'd say to both of the above. When I started shooting High Power matches with my Garand, my target frequently looked like yours. I didn't know it at the time, but my trigger control (read flinching and yanking the trigger) was awful. I really didn't comprehend the concept of follow-thru at the time. Also, thanks for the info Bob S. I'm going to copy/paste it for future reference. I'll also recheck my sights at the range to see if they're close to the info above.

[Mr. X]

Well, certainly the first thing you need to do is check to make sure that neither the front not rear sights are moving around, and that the action is not moving around in the stock.

Assuming that is not an issue, I would recommend paying a lot of attention to your front sight AND your trigger control. I have found that it is commonplace to shoot low in the rapids, especially with a .30 cal, and that I need to change the hold to a center-mass on the raps. Also SLOW DOWN in the raps and follow through. There's a subconscious tendency to pull the rifle down with the sling and the trigger if you're holding at 6 o'clock in the raps and the shots end up in the white.

Same for the offhand. I think that when you hold at 6 if you don't pay close attention to your trigger control you end up pulling the shot low.

Finally. although I don't think that this is the cause of the group placement errors, you may be able to tighten up the group size by considering a slower powder for that bolt gun, like 4064, 4350, H414 or something like that. 2015 seems to me to be a bit fast of a powder to use in a 30-06 with a 168 grain bullet. (While we're on the subject, my personal belief is that if you're only shooting at 200 you might just as well use a 150 grain bullet, which is less expensive and might recoil slightly less).

HTH