vertical stringing ?

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by splattermatic, Jan 14, 2009.

  1. splattermatic

    splattermatic Well-Known Member

    Nov 15, 2006
    i recently traded for an er shaw commercial fn mauser action built 338-06.
    it's great rifle. nice laminated stock, timney trigger, luppy mounting hardware and scope...
    no matter what bullets i've used so far and no matter what powder behind them , this thing will only do about 2 inches at best and most of the time is vertical...
    i rebedded it, redid the mountings, and blue loc tited them, the crown looks good , nothing touching, i mean i checked action screw torque, etc... with hornady 200's i am about .025 off at mag length and with 225 tsx's about .050. i haven't tried longer, nor shorter yet... think it my help?

    i am about to say f it and rebarrel..... but i don't want to quit, i want to beat this thing and get at least a consistant 1" group for at minimum 3 shots...
    this is the first rifle i cannot get to shoot...

    any ideas why the vertical stringing, horizontal it keeps 1/2" to 3/4" "groups"...

    if i rebarrel i'd like to go 6.5-284.....
    can a mauser shoot itty bitty groups ?
    Last edited: Jan 14, 2009
  2. KQguy

    KQguy Well-Known Member

    Dec 7, 2007
    Do you chronogragh your shots?Sounds like you are getting high SD's.Also experiment with different primers,those can lower SD's.Also,try to let the barrel cool completely before each shot,to see if that makes a difference.

  3. J E Custom

    J E Custom Well-Known Member

    Jul 29, 2004
    Normally if you have real good loads like KQguy said then the problem
    could be trigger control.

    Vertical stringing can be caused buy a poor trigger or an inconsistant grip
    on the rifle and finger placement on the trigger.

    Horizontal stringing is normally caused by poor bedding or floating allowing
    the action to move around.

  4. Boss Hoss

    Boss Hoss Well-Known Member

    Nov 10, 2005
    This pretty much covers it all --- put together by one of the best shooters and builders on the planet Speedy Gonzalez read and learn but most importantly incorporate this into your shooting and increase your skills:

    Tips on Vertical Problems

    1. A lot of rifles are muzzle heavy. Some rifles have too heavy a barrel and this causes vertical problems, especially those who shoot free recoil

    2. Firing pin coming out of hole in bolt in the cocked position. This will cause poor ignition. Take bolt out of rifle and look in firing pin hole. If you cannot see entire end of firing pin it has come out of the hole.

    3. Firing pin dragging in bolt or shroud. Listen to the sound when you dry fire. If not the same sound each shot something is wrong.

    4. Trigger sear too much spring. Hold trigger in firing position and push down on sear with your thumb. If it is hard to push down, this will cause vertical problems.

    5. Firing pin spring too weak or too strong will cause vertical problems. If you think this is the problem change springs and see what happens.

    6. Tightening front sand bag too tight on stock. When you try to pull rifle back by hand and rifle feels like it is stuck in the bag it is too tight. Rifle should move in sand bags evenly, not jerk or chatter when pulling back by hand.

    7. Action not level with top of stock running down at muzzle end. Rifle will recoil up at butt end causing vertical.

    8. The load that are shooting can too light or heavy and can cause vertical problems.

    9. Bench technique not same every shot. One example, should against stock one shot and not the next.

    10. Bad primers – if getting vertical try other primers.

    11. Bad scope, if scope is bad from shooting vertical, if you change your load in anyway and vertical goes away it is not your scope.

    12. Rifle not balanced, it does not recoil right, jumps in bag. If rifle is built properly this will not happen.

    13. Some stocks are very flexible. This can cause vertical.

    14. Front sandbag too hard. I personally have never had a rifle that will shoot consistent with a rock hard front sandbag. It always causes vertical or other unexplained shots.

    Other Tips:

    1. Head on front rest loose. A lot of rests have movement even when you tighten them as much as you can. This can cause unexplained shots.

    2. Some 30 mm scope rings are not getting tight enough to hold scope. Scope slipping in rings under recoil. This will cause point of aim movement.

    3. Keep shell holders clean, in press and priming tool. I have seen so much dirt in shell holders that cases are sized crocked on body. Also primers cutting primer pockets bigger shaving brass as you seat the primer.

    4. Whenever you can, set up so you can load watching conditions on the range as you load your ammo. That way you will be aware of any changes in conditions since your last group and you will be mentally prepared for the new condition.

    5. Learn to look at whole field of flags, not just the row in front of you. A lot of times conditions change away from you will cause shot to go out of group before change in condition shows up in front of your bench.

    6. When you chamfer the inside of your case necks make sure they are smooth enough that they don’t peel jacket material off when you seat the bullet.

    7. I see people walking around with case necks turned up in the loading block. A lot of the time there is condensation dropping from the roof of your loading area. If one drop of water gets in case you are in trouble on the shot. How many times have you had a bad low shot when it has been raining and you have been walking around with your cases turned up in your block?

    8. Learn to keep head down and follow through when you are shooting each shot.

    9. I hear a lot of discussion about low shots in a group and apparently this occurs a lot on the fifth shot. If it is your 5th shot most of the time you can bet you are doing something at the bench.

    10. If 5th shot is a problem, which everyone does at times, we do what I call wishing the last shot in. We just aim, pull the trigger, and do not worry about the wind flags.

    11. This year alone I have seen nine lock rings on scopes that are not tight. Guess what that does to your group? Make sure yours are tight.

    12. When you realize that the wind is your friend you will become a much better benchrest shooter.

    13. Practice in wind, not in good condition.

    14. Pay attention to angle changes on flags. Even though you see the same color angle changes make a big difference in your groups.

    15. The longer you wait between shots when a condition is changing the more the condition change will affect your bullet.

    16. If you do not know how to read wind flags or have never seen a wind flag try to shoot your group with the flags all going in one direction.

    17. Equipment at bench has to work flawlessly. If it doesn’t get it fixed or get rid of it. We need all our attention on wind flags.

    18. Learn to shoot with both eyes open so you can see more of the conditions.

    19. Free recoil shooters should be sure rifle hits shoulder squarely on recoil, not on edge of shoulder or muscle of arm.

    20. Should have your own stool to sit on so that you can sit at the bench comfortably for you.

    21. Hunting rifle barrels – do not get cleaned enough. If you keep barrel clean it will shoot better for you. You should clean barrel good after every 10 to 12 shots.

    22. Most hunting rifles will not put first shot after cleaning with rest of shots. So after cleaning if you have a rifle that won’t group first shot shoot one fouling shot before going hunting or before you shoot for group size.

    23. When working up a load for your hunting rifle take your time and do not let the barrel get hot on you.
  5. 3006savage

    3006savage Well-Known Member

    Jul 16, 2008
    Splatter as a last resort before a rebarrel you may want to try Tubbs Final Finish especially if the rifle builds copper. It cut my groups just about in half. I used 1/2 the bullets in the kit and the kit was only $30.00.
  6. Buffalobob

    Buffalobob Writers Guild

    Jun 12, 2001
    I know that one very well. :D

    BTDT this year with the kids. They would grab the eyepiece ring on the NF to turn the power up and down. Lucky the thing didn't fall off and get lost in the woods before I discovered it. lightbulb
  7. splattermatic

    splattermatic Well-Known Member

    Nov 15, 2006
    so, most of that doesn't apply to me !!

    i can and do shoot sub moa groups regularly with rifles that can do it.
    i shoot benchrest comp's occasionaly as well.
    it's not me...

    i am going to go to a max load of varget, which seems to be the best producing powder for group size right now, followed by rldr 15. right now i am 2 grains under max for the varget loads with 200 grain hornady bullets, showing n flattened primers yet, so max we go...

    then i am going to try putting a strip or 2 of thin cardboard under the barrel near the end of the forearm and retighten and see if some light pressure may help ...

    shoulda known better than to get a shaw pos, but noooo.....
    just couldn't resist a nice looking rifle in a caliber i have wanted for a long time...
    i wanted to shoot 225's or 250's at a decent velo, for pa. whitetails...
    something heavy to flatten them....
    didn't want to slow the 338 win mag down too much, and wanted to keep in the same caliber for ease on the wallet bullets for both guns.

    i am also going to go buy new virgin 30-06 brass and see if that may make the difference.. using 1x fired, straight 338-06 resized, trimmed to even up the necks, deburred, primer holes uniformed, deburred and loaded.... just like most of the rest of the stuff i shoot....
  8. davewilson

    davewilson Well-Known Member

    Feb 19, 2004
    i'm betting it's the lugs in the receiver. one of them is engaged with more pressure than the other. didn't the military blue print those actions before they were shipped off to war?
  9. splattermatic

    splattermatic Well-Known Member

    Nov 15, 2006
    don't think this one had that treatment ... it's a commercial fn mauser action.
  10. cinch

    cinch Well-Known Member

    Jun 4, 2006
    You may want to think about switching to one shot groups. Did you try the CCI250's?
  11. splattermatic

    splattermatic Well-Known Member

    Nov 15, 2006
    not yet. i had made these up and put fed 's in em, too pricey to waste.
    gonna try imr 4064,rldr15 and varget again tomm. which ever get the tightest group, will get new primers, cci's, and see if groups change....

    and what it looks like..

    Last edited: Jan 15, 2009
  12. Augustus

    Augustus Well-Known Member

    Jan 6, 2008
    I did some dry firing recently with a custom built on a 700 action. I started out on a bi-pod with rear bag, the target was at 100 yds. I got cumpfy and squeezed it off while watching for shooter induced movement. Wow, there was 1/2 min of jump straight up. To make a long story short, this jump is caused by the movement of the firing pin. I checked another 700 and a 660, both of these exhibited the same problem. Generally the movement was fairly consistant, 1/2 min straight up; however in a string of ten cycles one or two would show 1/4 min. periodically there would be no movement at all or there might be a little lateral movement. I thought it was the bi-pod causing this so I switched to sandbags. This proved to be far more erratic and unpredictable. After playing with the bolt guns I switched to two AR style rifles with JP triggers. I was expecting them to exhibit more movement than the bolts guns. Much to my surprise thre was no detectable movement from these rifles when dry firing from bags or a bi-pod. I said all that to ask this. How much does this movement affect accuracy? Personally I think the movement has occurred prior to the bullet exiting the barrel. Your thoughts on this matter would be appreciated.