300 Win Mag issues

Discussion in 'Reloading' started by MAHMOODB, Feb 17, 2014.

  1. MAHMOODB

    MAHMOODB Member

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    Hi. Ive got a 300win mag in a howa m1500. I have tried using siearra 180 gameking, noslet ballistic tip 180gr barnes tsx 150gr, and our local gs customs 160gr. Ive tried many different loads and they all group fair. The gs customs and siearra group very well at 100m. Pass a 100m out to 200m i wouldnt even call it a grouping. I have tried plenty different loads as well as seating depths and nothing makes it any better. At a 100m i get a 1moa grouping and sometimes even a half inch grouping. What can be the problem as i am frustrated now. When i recieved the rifle i changed the stock to a embidextrous thumbhole stock from boyds. The stock fitted perfectly without any work needed. The barrel is free floated but the action is not glass bedded. Can the problem be the stock by any chance
     
  2. Trnelson

    Trnelson Well-Known Member

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    Check the silly stuff first. Are the the optic mounts and rings uniformly torqued? Maybe the optic is no good. Try another known optic on the rifle and see if you can eliminate the optic as a problem variable...
     

  3. RT2506

    RT2506 Well-Known Member

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    I would bed it if it was mine. It needs to fit tight not just drop in. No insult meant but also have someone else that is a known good shooter also shoot it. I can't tell you how many bad shooting rifles have been fixed this way. :D
     
  4. DocDoc

    DocDoc Well-Known Member

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    What is the twist? If you are getting moa and less at 100 m/yds, it should not be a pattern beyond that distance, unless the bullets are not stable.
     
  5. MAHMOODB

    MAHMOODB Member

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    HI. The scope is a ziess hd5 conquest so it s not the scope. the twist rate is 1:10. The action is not bedded and i was thinkimg of doing that first. maybe ill bed it and take the scope off and remount the scope and see what happens. my problem though is if it was the scope it would give me the same issue at a 100m already. it would just enlarge the problem at 200. but this is a superb grouping at 100 and no grouping at 200 and beyond.
     
  6. lloydsmale

    lloydsmale Well-Known Member

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    yes its doubtful that if the scope is working at a 100 its the problem but do keep in mind that just because its a quality scope doesnt mean it cant go bad. ive had even the best brands fail at times. Somethings causeing instability in those bullets. My first guess would be to look at your muzzle crown. But ill add this. A buddy of mine whos a very knowlegeable rifle crank had a winchester 7mag that would drive nails at a 100 and shotgun patterns at 200. He never did find the problem with that gun and tried about everything. FInally he just gave up and traded it off.
     
  7. baldhunter

    baldhunter Well-Known Member

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    By all means,bed the recoil lug at least.That will keep it from walking around.Make sure there is no stress when you put your stock on.When you loosen the action screws you should feel very little movement as you loosen them.If you do,you may have something binding which can cause accuracy problems.As mentioned before,do the easy stuff first.Seating depth of your bullet can also be a big factor in your longer range groups too.I have a 300 Win Mag I just could not get it to group well at 200yds.I was at the point I was considering a custom barrel job.I ran the Tubb's Final Finish through it and I was very pleased with the results.I also did another rifle after that and got very pleasing results from it too.See my post on this thread,it was the last reply when I looked at it.
    http://www.longrangehunting.com/forums/f19/final-finish-daved-tubbs-129550/index2.html

    Here's some videos on this product,worth watching.

    http://www.davidtubb.com/store/Videos
     
    Last edited: Feb 18, 2014
  8. TJAY

    TJAY Well-Known Member

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    I found one time while shooting at 300 yards I was having group problems. At 100 they were great at 300 not so. I found that how I held the rifle made a great difference. A light hold was a bad group and when I pulled it in tight and held firm they tightened right up. Just a thought.
     
  9. Timber338

    Timber338 Well-Known Member

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    I would not count the scope out of the equation just because it is a Ziess. I went through a similar exercise years ago and changed out everything.... stock, barrel, trigger... in the end it was a brand new Leupold VX3 that had a defect from the factory. So just sharing my experience with a rifle that shot bad where I never thought the scope would have been the problem.

    Although I agree that your problem does not point to the scope... but to play devils advocate, could it be a focus issue within the optics? maybe the scope is focused correctly at 100, and then a parallax/focus defect is causing error at longer ranges. Not likely if you have side focus (which I think the Z5 does have), especially when shooting from a bench where your hold is very consistent.

    I do agree with others that a bedding job would be good just to eliminate the stock as a potential problem.