Could Mag primers bring down my ES?

Discussion in 'Reloading' started by Lazerus, Aug 17, 2014.

  1. Lazerus

    Lazerus Active Member

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    Out shooting my 6.5 284 Norma, I have got a pretty accurate load that is doing well under 1/2 inch at 100 yds. 130 grain Cutting Edge bullet with re loade 22 powder, consistently giving me good groups, but my ES hovers in the 30-50's. H4831SC and Hybrid 100 V commonly give me an ES in the 4 to-7 range, but groups are twice as big. The primer that seems to be the most accurate with the Re loader 22 is the Win LR, but with an ES in the 30's to-50's, I know it will not hold long range. My question is, should I try a Winchester primer in Magnum. I have tried other primers with the Re-loader 22 all with worse results. Here is an example, 30 50 30 98 30 54 30 84 31 08. My best is a half grain lower in powder charge. 30 33 30 16 30 13 30 25 29 99. Any advice would be greatly appreciated, you guys have always been extremely helpful!
     
  2. Lefty7mmstw

    Lefty7mmstw Well-Known Member

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    That's just about the same issue I often have with my 270's. I've got a time getting my es down below 50 with those two rifles but they shoot so well I hate to scrap the loads. Hotter primers usually help with cold weather ignition but actually worsen es a bit. Have you changed your neck tension or played with powder charges to see if that helps? I'll sometimes see a charge that crowds the top too much have too much es.
    I'm not the best at straightening out es issues so I'll defer to others on their ways to play here.
     

  3. cowboy

    cowboy Well-Known Member

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    If you have only shot your loads at 100 yds I would suggest testing those same loads as far as you are capable or confident in. How accurate is your chronograph?

    If those same loads were shot at say 500 yds and you only got minor vert. differences I would say the heck with a bad ES and get to practicing/hunting with that load. You can beat yourself silly over some chrony readings. No matter what I get off a chrony I field verify and field verification always over rides chrony readings IMO.
     
  4. Mikecr

    Mikecr Well-Known Member

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    I agree with the other fellas.
    You could of course try every primer availale, or you could adjust your firing pin strike with the better shooting primer.
    It's likely you'll have to re-tune with primer changes in order to isolate the primer's affect.
     
  5. FearNoWind

    FearNoWind Well-Known Member

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    I agree that, before you start changing things in a good load formula, stretch out the distance and see how the groups hold up. I experienced some disturbing ES data with a chrono I had a year or more back that, until I figured out that was my problem, caused me to look at things that weren't actually wrong.
    If you must mess with the load, start with neck tension. Turn necks, measure their thickness, select only matching cases (neck thickness, trim length, weight, capacity) in the set before you load. Use a certified accurate neck sizing die, measure each bullet and match them up in sets, apply consistent seating pressure and check for perfectly matching CBTO data before you change anything else. Of course, use a high quality chrono that is properly set up.
     
  6. Lefty7mmstw

    Lefty7mmstw Well-Known Member

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    same here on field over chrono... heck I've got a few loads I haven't really chrono'd that are doing very well for me. I plan to get them over the chrono, but the wind here makes it a pain to set up the chrono at times. Take it to 1/4 mile or better and see if it does well or sprays, then worry about chrono #'s if you have grouping issues. If not, don't worry. be happy.
     
  7. idaho elk hunter

    idaho elk hunter Well-Known Member

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    Debur your flash hole
     
  8. RT2506

    RT2506 Well-Known Member

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    +1 on that. I could not believe how accuracy improved when I started deburring the inside the case flash hole. But like others have said I would then stretch the yardage out and do testing.
     
  9. coyotezapper

    coyotezapper Well-Known Member

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    Read this and then make your own decision on what to do next. Beware there is a lot to read here.

    Long range load development at 100 yards.