Pressure signs way below max load

Discussion in 'Long Range Hunting & Shooting' started by Mc Fraser, Aug 17, 2019.


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  1. FEENIX

    FEENIX Well-Known Member LRH Team Member

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    You might also want to re-visit page 80 your latest Hornady reloading manual.
     
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  2. Mc Fraser

    Mc Fraser Well-Known Member

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    I have that tool and I used it.
    To clarify, I measured the CBTO for a 215 Berger VLD Hunting with 2 methods and 5 measurements each, all 10 measurements came in very close:
    1. Sharpie
    2. Hornady Overall Lenght gauge with Hornady 300 wm modified case.
    And I measured the distance from the bolt face to the ogive with the cleaning rod.
     
  3. DT400

    DT400 Well-Known Member

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    Hmm OK I wonder if you just have a tight barrel. Have you called Krieger about it? Maybe the barrel needs to be slugged.
    Has the barrel been scoped just to see? Couldn't hurt. Maybe if there have been a bunch of rounds through it it has gotten severely copper fouled. Doubtful if that barrel is hand lapped but you never know.
    How is the accuracy? How many rounds down the pipe since de-coppered if at all?

    Darrell
     
    Last edited: Aug 18, 2019
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  4. DT400

    DT400 Well-Known Member

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    Dupe post mods please delete
     
  5. Bravo 4

    Bravo 4 Well-Known Member

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    I’ve had a rifle whose max load was the start load in more than one manual. Even had the bullet out past factory spec (SAAMI?) OAL. Shot really well just didn’t take as much powder to get there.
     
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  6. Alibiiv

    Alibiiv Well-Known Member LRH Team Member

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    This was my thought right at the get-go when I first started reading the post. To eliminate a lot of measuring/mis-measuring/nomenclature and all the reloading stuff.....did you try a box of factory ammunition out of your rifle; go back to basics????? Did this condition start out from the beginning when you first started shooting the new build? Manufacturing processes can be subject to human error as with any product. Also I would be measuring the bullets that you have been using, I doubt this is the problem, however at this point I would not rule out anything.
     
    Last edited: Aug 18, 2019
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  7. Ted Sierocinski

    Ted Sierocinski Member

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  8. SlugFester

    SlugFester Member

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  9. Ted Sierocinski

    Ted Sierocinski Member

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    Have someone else other than the gunsmith that chambered the rifle to check the headspace. I had a similar problem with a 220 Swift and the headspace was off. The powder scale accuracy verification is essential and weighing a small caliber bullet is a good quick check. I assume that you are using the scale for other reloading without problems. Also any chance of mislabeled powder.
     
  10. Will Gray

    Will Gray Well-Known Member

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    Weight a couple of 100g bullets to verify your scale. What high pressure signs are you seeing, ejector hole marking the case or sticking cases and flat primers (change primer brand)? Are the primer pockets enlarged? Try some other brass. Shoot a box of commercial ammo (heavy bullets) and see how they do.
     
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  11. Sam Summey

    Sam Summey Member

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    Are your bullets jammed into the rifling? How much "freebore is there". I feel a magnum should have at least .020 freebore before the bullet engages the rifling.
    Most long range folks are shooting heavy long bullets, give them a little jump to get the bullet moving. I had one customer bring in a 264 WM with the ejector pinged into the bolt. He said he used his regular powder charge but switched to a monolithic bullet. It is substancially longer that a lead cored bullet thus taking up more of the internal volume of the case. End result excessive pressure.
     
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  12. dragonfly

    dragonfly Member

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    Your talking about a quality barrel, but two things, Is your chamber free bored somewhat? If not probably should be. Have you checked the bore dia. is it close to the min. You are talking about a 28in. barrell Those combinations could cause pressure problems. I have A .300 h&h 26 in. barrel with the same problem. I can't get close to max loads from the book. Tight bore I think is my problem.
     
  13. mmsports

    mmsports Member

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    Great Pics Feenix!!
     
  14. DT400

    DT400 Well-Known Member

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    When you used the Hornady COAL gage you used your current bullet right? You have to do this measurement for each type of bullet/weight/manufacturer etc. I have heard of the cleaning rod method...IMHO that's got to be less accurate then the Sharpie method.

    It sounds like you likely have correct measurement from using the COAL gage.
    BUT
    One question, after you have measured using the COAL gage how hard is it to get the bullet out of the gun? Can you just turn the gun muzzle up and the bullet just drops out with a light rap in the side? If the bullet requires using a cleaning rod or dropping the gun on the butt it's too tight. Ideally the bullet should just fall out when the muzzle is pointed up. It is a delicate process and requires a very light touch.

    Darrell
     
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