M1A Keeps Grouping Vertical Stringing, HELP

[waveslayer]

I have a new M1A with a Super Sniper scope. I have it zeroed at 100 yards. My first Cold Bore shots are dead on everytime. Once I shoot shots 3 and on it starts to do a vertical stringing. shots 3 and 4 are key holed, shots 5 and 6 are key holed and are about 1-2 inches higher then the previous groupings. What is causing this? I am using 175 Gr. Sierra Match, Winchester Brass, CCI primers with 44 grains of Varget.

 

[cox308]

Re: M1A Keeps Grouping Vertical Stringing, HELP

1.) Is your scope mount on solid? Properly torqued mount and rings? Did you use blue lock tight?

2.) Are you sure its not the shooter?

3.) You could be dealing with velocity issues. How far did you go prepping your brass? Did you weight sort both the brass and the bullets? How are your groups using factory Match Ammo?

 

[Frank Green]

Re: M1A Keeps Grouping Vertical Stringing, HELP

By key holing you mean the bullets are going thru the target side ways? If yes you could have multiple things causing this. Damaged barrel? Damage to the muzzles crown?

Has the flash hider been reamed for proper bullet clearance? If not enough clearance it can cause accuracy problems if really tight the bullet could be hitting the flash hider on the way out.

Flash hider's castle nut to tight? To tight and it will pinch the bore and cause accuracy problems. To loose and the flash hider will vibrate on the barrel and cause accuracy problems.

Is the gun built to National Match specs.? Guess I should've asked this first!

Is the rifles action glass bedded into the stock? If not get it glass bedded by someone who knows how to do them.

Is the gas cylinder and plate unitized (made as one assy.) some get welded together etc....

Is the gas cylinder figure 8 nut to tight? When you tighten the figure 8 nut against the gas cylinder it should start to get tight around the 5 o'clock position and you should just be able to with your fingers pinch it down to the 6 o'clock position. If the nut is stating to get tight way earlier than this it will cause the barrel to bow upwards and cause accuracy problems as well.

One test you can do to check to see if the gas system is not causing accuracy problems is to turn the gas system valve to the off position (90 degrees). This way when you pull the trigger the gun will not cycle. You will have to manually pull the op rod back and let it fly forward under it's own weight (basically you turned it into a bolt gun)to chamber/load the next round. By doing this if the gun groups well and consistently there is something wrong with the gas system. First thing to do is to replace the gas piston.

Is the op rod binding? Remove the recoil spring and guide. Tilt the gun up and down and at a certain angle(I forget the angle) the bolt and op rod should move freely with out any help from your hand. If it doesn't something is wrong. I've seen bent op rods and or rewelded op rods that were bad.

Also for proper accuracy and functioning the gas piston should be cleaned regularly to remove build of carbon. You can get tools with handles that have the proper size drill bit on them and you use them to scrap out the carbon build up. Creedmoor Sports or Champions Choice should have them. To much carbon build up and it can effect the gas pulse and the bolt could start to move before it should (before the bullet has left the barrel) and this will cause accuracy problems also.

When a M1A/M14 is properly set up they can be great shooting rifles. If not set up properly or are stock GI type guns they can give you fits like you wouldn't believe.

Some of these things you can check yourself. Some by a competent gunsmith. If you are totally lost take the gun to a M14 type match rifle builder and have them look at it.

Later, Frank
Bartlein Barrels

 

[JoshcBoucher]

Re: M1A Keeps Grouping Vertical Stringing, HELP

Don't expect too much from the M1A platform. It was my "first buy", for precision shooting. It's a great rifle. Won't sell her, but I've "moved up". GAP 10!!!!!! They SHOOT!!!I got to 3 in. groups, at 100, with mine, and gave up. Could have put a grand into the gun, but bought another, instead. The GAP 10 shoots 3/4 in, at 100, with cheap ammo. 10$ a box stuff.Get a GAP 10.I got a DPMS SASS, and a TRG 42, in the "mean time" and the GAP shoots as good.Just me.

 

[stu2]

Re: M1A Keeps Grouping Vertical Stringing, HELP

I had the same problem you did. I had an M14 EBR setup with a scope mount that allowed the ejecting brass to hit the scope. I switched to a scope mount that covered the action and that corrected the issue. I'm not sure how you are set up. Also, recoil could be causing your bullet length to change. Make sure your overall length isn't changing on ammo that's in your magazine as you fire. You can correct this problem by crimping or taking your expander on your sizing die down .001". This would give your a .003" grip instead of a .002" grip on the bullet.

 

[stu2]

Re: M1A Keeps Grouping Vertical Stringing, HELP

Both of mine are 1 MOA guns on handloaded ammo. I think that's pretty good for an M1A. I never tried Varget. I use 41.3gr H4895 with 168gr bullets in both of my guns.

I agree, the GAP 10 is the shnizzle. I have mine on order.

 

[McCrazy]

Re: M1A Keeps Grouping Vertical Stringing, HELP

Frank- I believe the keyholing the OP was referring to is that his shots are touching for 3-4 and 5-6, not keyholing as we use for bullets hitting the target sideways.

Love your barrels BTW

 

[Frank Green]

Re: M1A Keeps Grouping Vertical Stringing, HELP

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: McCrazy</div><div class="ubbcode-body">Frank- I believe the keyholing the OP was referring to is that his shots are touching for 3-4 and 5-6, not keyholing as we use for bullets hitting the target sideways.

Love your barrels BTW </div></div>

Wasn't thinking about how it was grouping referring to the key holing. Thanks for adding that. I've seen guns that the bullets would come out and at a 100 yards the bullets would actually key hole on paper.

Thanks for the comment on liking our barrels!

If you have a standard box M1A/M14 and with good ammo is printing groups around 1.5" to 2" it's a good gun.

A match built/prepped gun will get down to 1/2"moa and do it consistently but they need to be maintained in order to do that on a regular basis.

As much as I like the M14 there are a lot of things that work against it. The M1 Garand is still my favorite rifle and I love to pull mine out and just shoot them once in a while regardless of how well it shoots.

Later, Frank

 

[BCP]

Re: M1A Keeps Grouping Vertical Stringing, HELP

My m1a does that too I attribute it to the action not being bedded in the stock.

 

[BCP]

Re: M1A Keeps Grouping Vertical Stringing, HELP

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Frank Green</div><div class="ubbcode-body">
When a M1A/M14 is properly set up they can be great shooting rifles. If not set up properly or are stock GI type guns they can give you fits like you wouldn't believe.
</div></div>

I'm there right now, I want my 308 AR back

 

[Frank Green]

Re: M1A Keeps Grouping Vertical Stringing, HELP

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: BCP</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Frank Green</div><div class="ubbcode-body">
When a M1A/M14 is properly set up they can be great shooting rifles. If not set up properly or are stock GI type guns they can give you fits like you wouldn't believe.
</div></div>

I'm there right now, I want my 308 AR back

</div></div>

The AR15 platform guns being used in match rifle/service rifle competition (especially when the 75-80gr bullets came out) is what killed the M14 in competition. The AR type guns you have no bedding to go sour, and for the most part no gas system/piston/op rod issues etc...to give you grief. The AR type guns are way more forgiving when it comes to accuracy and holding the accuracy over a long period of time.

Later, Frank

 

[waveslayer]

Re: M1A Keeps Grouping Vertical Stringing, HELP

Thanks for the help. I should had clarified the "key hole" It's not Key Holing... They are touching, figure 8's. The rifle is brand new, it has about 40 rounds through it. I will try the gas rod and also the bullet seating depth changing from the recoil. I haven't crimped the bullets so that may be my problem. These rounds were made for my Rem. 700. Thanks again

 

[waveslayer]

Re: M1A Keeps Grouping Vertical Stringing, HELP

What's your seating depth and how much crimp are you adding to your rounds?

Also, what's the length of your brass. I will try your loads. I just haven't had time to load some for this rifle. The nearest range to shoot is over an hour away. I just had these extra rounds in my safe.

Thanks

 

[Muskyjerk]

Re: M1A Keeps Grouping Vertical Stringing, HELP

when cleaning your rifle leave the stock on. a wise camp perry shooter told me the action will settle in. if you are using a glass stock disregard but wood leave it in..

 

[sgj2025]

Re: M1A Keeps Grouping Vertical Stringing, HELP

M14 is a special girl, meant for harms way not accuracy. I have two, she will eat anything you feed her and with really good ammo get me 1.5 moa at my command. My ARs are more accurate but also more less tolerant of shitty ammo. She is a pig, but she is mine. Dont try to make it something it is not!!!

 

[superjc]

Re: M1A Keeps Grouping Vertical Stringing, HELP

I appreciate the info given here. I have a 22" bbl NM that I've never been able to do more than 4 MOA with and I know there is carbon buildup in the gas plug area (I have to get those drill bit tools!) plus I have only ever shot crappy milsurp through it like South African.... and don't shoot enough to not be able to rule out my own skills... although I recently did some nice 2 MOA groups at 100 yards with my Imbel PARA FAL & ElcanSpecterDR (and that trigger is AWFUL compared to the national match)....

 

[BCP]

Re: M1A Keeps Grouping Vertical Stringing, HELP

168gr federal gold medal match will make it shoot tighter. With my usual loads of 41.5gr Varget, LC brass and a 175smk I shot several 1.5" 5 shot groups @ 100 with mine. After about 20-30 rounds it begins to heat up and wander around in a 2-2.5MOA circle which is unacceptable to me. Time to figure out bedding.

 

[cal50]

Re: M1A Keeps Grouping Vertical Stringing, HELP

Your rifle needs to be tuned and bedded properly. As other have mentioned above for checking part fit and function.

Make sure you have adequate barrel tension and this is set when bedding. You should also put a dab of synthetic grease under the front stock ferrule where it contacts the gas cylinder. When the barrel moves the gas cylinder need to return to the same place on the stock ferule for consistency.

How to bed an M1A /M14 properly-

http://m14forum.com/m14/128315-bedding-rear-lug-gun-coat-hanger-way-pic-heavy.html


Set your gun up properly and make sure its right , use quality ammo and try again. The M1A can be made to run MOA but it takes good parts fitted correctly and bedded right.

 

[Douglas-001]

Re: M1A Keeps Grouping Vertical Stringing, HELP

I started out shooting the 14 at Camp Perry. It was the only rifle I had that qualified as the service rifle. I've learned a few things over the years, and I still shoot Bestsy (rifle's name).

Scope mount. What kind do you have? Sadlak has a great selection and Mike is a stand up guy. I've spoke with him at Perry a few times.

That load sounds hot. These gas rifles - M14, M1 Garand - like a particular burn rate. I use IMR 4895. 41 grns. w/ 168, and 40.5 @ 600 w/ 175's. The fastest round is not always the most accurate. I don't know what kind of QC you may be exercising on your process, but you shouldn't reload that brass anymore than 4x's with these platforms.

Are you getting a cheek weld, or a chin weld. The scope will sit high on the rifle leading to misalingment and recoil on the chin is no fun.

You need to full length resize that brass for the 14. I actually use a small base for competition loads during rapid fire stages. I've never crimped a match bullet in my life.

I use grease on my 14's. No oil. Be sure to build a solid position as it will push you around. Shoot with the irons until you out shoot that capability, and then move into the optics. The M14 Rifle Association website has gobs of info, and everyone is always helpful. This platform will require some work and upkeep, but spend a little time with it and they hold the 10 ring all day. I know Betsy does at the long line. That's all I'm after anyway. Good luck and good shooting!

Doug

 

[millbastard]

Re: M1A Keeps Grouping Vertical Stringing, HELP

Try using the 1907 sling if you don't already. Even if you use a rest, a good leather shooters sling properly used and adjusted nice and tight will definitely make a difference or narrow down the real problem. Turner Sadlery makes a nice one.

 

[81STFACP]

Re: M1A Keeps Grouping Vertical Stringing, HELP

I am with Doug no need to crimp match ammo even shooting them thru the 14s, just make sure you have enough neck grip on the slug, 3 to 4 thou down from a loaded round is sufficient. I've shot Ks of uncrimp rounds in competition thru my 14s with no ill effect.

Sometimes the cold bore shooter is more like the issue than the rifle cold bore shot. Best thing you can do with your 14 is to have it fully accurized by a competent smith.

Hi Doug!


nez

 

[JeffinTX]

Re: M1A Keeps Grouping Vertical Stringing, HELP

to the OP: 3 things come to mind
1. the load is too warm for the m14/m1a. 42 grn of Varget/RL15 does real well with 168 or 175 in my M1a and is safe for that action. The M118LR that was developed for the bolt guns had to be downloaded when the M14 was brought back online, and it was causing premature failures. If you hear a pinging or ringing sound from the receiver after firing a round, its too warm.
2. With a scope, the standard stock is too low and doesn't give you a good, consistent cheek weld. Need to build the stock up so that you do.
3. If this is a standard M1a or the "loaded", then its not glass bedded. This is one of the first things the "accurize" the M14/M1a. Otherwise, the gun may "walk" as it warms up. My stock M1 Garand does that too from a cold barrel. I think this is most likely the culprit.

Good luck. The M1A is a fun rifle to shoot and can be very accurate, but it does demand a tighter position than the AR's or bolt guns.

 

[Douglas-001]

Re: M1A Keeps Grouping Vertical Stringing, HELP

Waveslayer,
Get some commo going with Nez-81STFACP-he's the real deal with the 14. I've seen this man shoot and have had the honor of receiving his advice while on the ranges at Camp Perry on several occasions. No doubt there are many here who shoot these platforms very well, but Nez is the only one I have met and know personally. All postings give great advice and are a testimony to the ability of the rifle when the shooter invests some time to this platform. Good luck and good shooting!

Doug

P.S. Bassett makes a good mount also. I had one for awhile and they really hold a zero.

Hi Nez! How's about my avatar pic? Capital U-G-L-Y!! And that's my good side!

 

[81STFACP]

Re: M1A Keeps Grouping Vertical Stringing, HELP

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Douglas-001</div><div class="ubbcode-body">
Hi Nez! How's about my avatar pic? </div></div>

Hey you were the poster boy on the Springfield M1A Match flyer!

See you at the M1A Match at Perry this year, I'll show you the 1911 I won for being the High Senior last year.