Accuracy issues with rifle

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by Tater1985, Jan 9, 2012.

  1. Tater1985

    Tater1985 Active Member

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    Oct 17, 2011
    I shot several groups out of my 7mm RM this weekend and am having some issues. This is an older Weatherby Vanguard with wood stock. The rifle is bone stock other than a Timney I dropped in, no bedding of any kind. I shot a couple MOA groups with this rifle at 200 and 300 yards one day, but am starting to wonder if it may have been a fluke or maybe just dumb luck. I do am in no way shape or form an expert shooter, I still need lots of work in that department, but I have shot several MOA and sub MOA groups with a couple varmint rifles.

    I could not get by Vanguard to shoot better than 5-6" 3 shot groups at 200 yards. I did shoot 2 groups at 100 yesterday just to see what they looked like. One was about 1.5" and the other was about 1.7". I am not waiting 5 minutes between shots, just single loading one shell at a time and taking my time, probably 1 1/2 to 2 min between shots.

    I am shooting the 168gr Berger VLDs by HSM (in signature). I know Berger says that these bullets are picky about seating depth and finding your COAL sweet spot, but I have shot some groups with other ammo and get very similar results, almost identical. I was wondering how sensitive the COAL is to accuracy? I measured 3 of the HSM cartridges this morning before work, and I got 3.350", 3.346", 3.356". Is .010" quite a bit for ammo that should have been made in the same batch?

    I am very interested in shooting the Bergers. I do have access to reloading equipment, but pretty much don't know anything about it. In your opinion do you think I would be better off altering the rifle for improved accuracy or handloading to try and find the COAL sweet spot? Thanks.
     
  2. 7stw

    7stw Well-Known Member

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    You possibly have one of two or two of two possibilities. Factory ammo is is a hit or miss, (pardon the pun) situation. That is a possibility, but that HSM ammo is good stuff and usually shoots better than that. The other variables are in the gun. Are the stock screws tight, is there barrel contact in barrel channel somewhere, fouling in barrel, or is the barrel broken in. Berger bullets are awesome to shoot , and sometimes take a little work to find that sweet spot, but when you do find it, man they are awesome.these are just a few things that come to mind with the given details, and I hope this helps. Good luck. lightbulb 7STWgun)gun)
     

  3. RT2506

    RT2506 Well-Known Member

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    Bed the action and float the barrel and shoot from a SOLID sand bag and press benched position. Have your trigger pull down to at least 2.5 lbs also. Then you need to start handloading. Belted cases shoot best with a case that just kisses the shoulder. Seating depth makes a world of difference in accuracy. Were you measuring your ammo from bullet tip to base of case? All bullets are not the exact same length from base of bullet to tip. You need to measure you COAL to the o-give of the bullet from the base of the case. The base to o-give of the bullet will be the same length if the bullets are of the same lot made on the same machine. I have shot a bunch of so called "not accurate" rifles and found out that the fix was to tighten up on the nut behind the stock. :D
     
  4. Tater1985

    Tater1985 Active Member

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    You're right about he nut behind the stock! I am looking into having someone local do a bedding job on it. As far as floating the barrel, I have noticed that there is a pressure pad under the barrel in the fore end of the stock. The barrel is suppose to be floated, and is part of the way, but the stock does touch in a place or two (I tried with a dollar bill). My trigger pull is down to about 2.5 on the Timney I put in.

    I was measuring from tip to base. Can you explain to me how to measure from base to ogive? I understand where it's at, and while I can try to come up with some way to do it, I am interested in how it's commonly done. It seems like I will need some type of jig or something. Thanks.
     
  5. RT2506

    RT2506 Well-Known Member

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    You need a bullet comparator to do your measuring. Hornady makes one called the Lock-N-Load bullet comparator. midwayusa.com has them Product # 709-931 for $16.99 for a kit with the most popular cal inserts. It fits on your dial calipers.