K98 verticle stringing?

[TheVision]

https://www.milsurps.com/images/impo...ad3916b5-1.jpg heres the crown redo i did with hand crowning tool

Vertical stringing is often indicative of inconsistent ignition due to a firing pin issue (firing pin worn, spring too weak, ...). Check that before you part the gun out.

Information

Warning: This is a relatively older thread This discussion is older than 360 days. Some information contained in it may no longer be current.

[mac1911]

I have heard of this condition...I will post my results. One thing I did find out about this gun is the owner removed the shims he had in it to use in another K98 he has. He didnt mention that at the time. IO found this out from another friend of his. I found several several articles on what to check for proper stock,band,handguard,action fit. The Fpin actual looks very good under the magnifyer. Nice clean no pits ect ect. I have nothing to judge the spring with. Looks good, no rust,kinks,nice flats on the end "feels" strong.
It will be a few weeks before I get back to this. I will post results.

[Patrick Chadwick]

One thing I did find out about this gun is the owner removed the shims he had in it to use in another K98 he has.

That sounds as if the previous owner had fudged the bedding. Loose shims are not the best answer. Start from scratch and check everything.

What follows is not holy writ, just my pragmatic method:

1) The recoil bolt MUST sit firmly in the stock, and not rotate if you try (gently!) to turn the nut.

It is exactly this action that loosens the fit of the bolt in the wood when Bubba decides that the d..n thing must come out at all costs! One frequent mistake of misguided people who want to make their Mauser stock look pretty is to remove the recoil bolt in the course of the all-too-frequent horror story of soaking the stock in caustic soda a.k.a. oven cleaner and then cooking it dry. If your rifle has been given this kind of treatment, then the chances are good that the stock is warped. Maybe not obviously, but enough to upset the bedding and, as a result, the accuracy. If the bolt is loose, it must be fixed before proceeding.

2) The recoil lug MUST sit firmly against the recoil bolt.

When assembling, insert the trigger guard screws lightly, stand the rifle on its butt, and bang it down on a piece of soft wood or hard rubber to make sure that the lug is indeed hard back against the recoil cross-bolt. Take a look at the tang at the rear of the action. It should NOT be hard back against the recess in the stock. If so, then this recess will be taking the recoil, instead of the recoil lug and bolt. Accuracy suffers and the condition can lead to a split in the neck (wrist) of the stock. This condition must be rectified before proceeding.

3) The action body MUST sit cleanly in the cut-out, being held by the trigger guard screws. It must NOT rock fore and aft.

4) When assembling, tighten up the trigger guard screws alternately front and rear. When fully tightened, the screws should be compressing the wood (elastic deformation), but not crushing it (permanent deformation).

5) It should be possible to slide a piece of thick paper all the way round the barrel at all positions between the knoxform and the muzzle. The bottom of the barrel may touch the wood right at the front, where the bayonet boss is attached, but the barrel should not be clamped by the bayonet fitting. Recommendations (depending on author) vary from zero (i.e. free floating) to 1 kilo/2 pounds upward pressure of the wood at the front end. Personally, I prefer zero to a pressure that will inevitably vary somewhat with temperature and humidity.

Go through the list above. I suspect that the rifle is unsatisfactory in at least one of these points. When (if?) you discover which point is wrong, we can consider how to fix it. A detailed description of how to fix all conceivable faults would require a substantial chapter in a book, not just a simple forum posting.

---------- Post added at 03:54 PM ---------- Previous post was at 03:48 PM ----------

heres the factory PPU match ammo....in both test runs the PPU shot below point of aim?

That could indicate that the barrel is indeed being clamped down by the upper band/bayonet fitting. See point 5). In effect, the barrel is being forcibly curved downwards and the varying shot position results from the conflict between the barrel and stock bending moments as the temperature varies.

[Patrick Chadwick]

The good news:

The photos that show an almost pure vertical stringing, with very little horizontal variation, indicate that the muzzle crown is OK and the bore is usable. Otherwise the shots would be all over the paper. But you can forget further testing with the ammo where the shots were indeed all over the paper - that is ammo that is no good, at least not for that rifle. Stick to the ammo that had the smallest horizontal spread, otherwise you are testing the ammo, not the rifle. And the vertical stringing is so extreme that you need not worry about subtle effects - it must be a fairly crass defect in the bedding.

BTW, trigger guard screws that are done up tight can mislead you if the boss is bottoming on the recoil lug, and you are in fact pressing metal to metal, but the wood has shrunk so that the stock is not being properly pinched (i.e. compressed). In this case, the screws may indeed be very, very tight, but the system is still not held firmly in the stock. It may be necessary to file a smidgeon a.k.a. gnat's whisker off the threaded boss on the recoil lug, so that the wood is still under compression.

[mac1911]

Thank you for the insight. Although I feel this barrel is on the thin side I do believe itstill has some fun shooting accuracy left.
As for the ammo. The surplus I have has been much like a "lets see". It also has improved in group size so far compared to the original test.
From this point on I will use reloads and what I have left of the PPU match.

[Leeroy151]

My rifle started stringing to the right after I proped it on my truck and then drove off and ran over the barrel with my back tire. It was in some soft mud which maybe helped reduce damage...but, at 100 yards, it does string to the right about one inch plus, three round groups...I guess as the barrel warms up.

[browningautorifle]

ran over the barrel

You CAN straighten that quite easily you know. Wish I was a bit closer, I'd do it for you...

[soyarm]

The RC saw some very heavy action on the Russian front for sure,,,well, if the Nazi lived very long before they picked up his rifle. If only these surplus rifles could tell their story.

[Calif-Steve]

Try removing the front barrel bands and put the handguard aside. Now try a 10 shot group. Grouping should improve. This is a start and good luck with the rifle.

[mac1911]

First off thanks to you gents for the tips. This old war dog has a little life left. Im not looking for a tac driver. I dont mind tinkering with these old irons. Helps me improve my skills. This might be a a new barrel project as soon as my barrel vice and action wrenches come in? Also like to thank majspud for this link. http://forums.gunboards.com/showthre...ussian-capture
Tutorial: How to restore accuracy to your Russian capture.

This was very helpful and also lead to some more good links. I did everything mentioned except any trigger work. Its a heavy *** trigger but breaks nicely and is smooth. Im used to heavy triggers. I also did the 11' DIY recrown with tool from midway.
All groups are @ 50 yards. I did play with elevation on some of the reloads. Next outing will to be to correct windage a bit and find a "best" of reloads to work with. So far im happy that I at least got it back to MOP, minute of pumpkin.


This is the 1960s surplus I got with the rifle had 2 duds in the 15 rnd box. many delayed ignition. Not a terribler hang fire but enough to notice! Not a spectacular group but considering I could fit 13 shots on the paper to not even finding the 5 shots from the first test...huge improvement


This is PPU new production "match" ammo not to bad


This here is with reloads. used nosler 200 gn FMJHPBT custom comps. H4895 powder useing Hodgdon DATA for reduced loads with H4895. They where very nice to shoot. Not powder puffs but very pleasant. I will be exploring these loads a little more. The verticle stringing seems to be alot better also.

I plan on doing some more reload testing. With the lands being as worn as they are at the muzzle im a bit shocked at how well this grouped even at 50 yards....now if the range lake would dry up I could do some 100yd testing.