Key to low ES on reloading

Discussion in 'Reloading' started by martyj, Jun 10, 2015.

  1. martyj

    martyj Well-Known Member

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    I would like to get my ES closer on my reloads and would appreciate any help.
    I full length resize
    weigh each charge to tenth of grain
    trim cases
    Weigh cases and sort them accordingly
    chamfer primer flash hole and case mouths


    What am I missing or doing wrong that I get a ES of 50 fps
     
  2. barefooter56

    barefooter56 Well-Known Member

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    Marty,
    SD is really more important than ES. SD ( standard deviation) directly effects vertical dispersion of the group. THAT is what makes the most difference in accuracy because you make the circle of the target wider. All of what you are doing can be important. IF you do change or try something new. Change ONLY ONE THING AT A TIME AND TEST! Try to get your SD down to 10 or below. The ES will come down too. If you need any more help please contact us here or at [email protected].
     
  3. Engineering101

    Engineering101 Well-Known Member

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    martyj

    Do you anneal your cases every 2 to 3 reloads? If not that will help keep neck tension consistent. Also powder selection can have a big effect - try a few others. An old trick to get low ES is to use a case crammed full of a powder that is too slow for the chambering. I've gotten single digit ES using that one. Good luck.
     
  4. martyj

    martyj Well-Known Member

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    Brass was fired twice so far.
    I do plan on starting to anneal as a matter of fact the stuff should arrive in the mail today.
    How come they recommend that you do not use the expander plug with bushing dies.
    Im using Defensive Edge dies and H1000 in 338 edge.
    The rifle itself seems to be very particular or least more so than any of my 300 rums.
     
  5. 8andbait

    8andbait Well-Known Member

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    People claim the expander will induce runout when pulled back through the neck. I use the expander in some dies and not in others, it depends.

    As far as ES goes, primers, powder type, annealing, consistent shooting form all play their part. Also, barrel fouling and heated or cooled ammo can have an impact depending on the powder.

    I would say anneal your brass first and shoot your regular load. You should feel less resistance while seating a bullet compared to your old brass. If that doesn't help then move on to powder or primer change.
     
  6. bruce_ventura

    bruce_ventura Well-Known Member

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    I'm in the same boat. I now have a 7 WSM load that shoots well in my rifle (group size~.75" ES at 100 yds for 5 shots), but the MV ES is high: 40 - 50 FPS for 5 shots. I used annealed cases for the last group of handloads.

    I'm thinking it's the Fed 215 magnum primers and will try standard long rifle and bench rest primers next. I have to switch over to a new lot of H1000, so now is the time to explore other primers as well. When I find a primer that minimizes MV ES I'll dial in a charge weight for the new lot of propellant.
     
  7. cowboy

    cowboy Well-Known Member

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    Very true.

    The one thing you did not mention is what chronograph you are using and how absolutely 100% confident you are in your chrony numbers on your ES.

    I would stretch your load out to the farthest distance you have available and shoot 5 rounds, measure your vertical spread. If you are say dead on in your vertical spread I would say you are either good to go or good to shoot your lying chronograph. I've seen way too many chrony's that should not be used as reliable 100% data. I always let my field test shooting override my chrony data.
     
  8. bruce_ventura

    bruce_ventura Well-Known Member

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    I agree^. I've long suspected, but have not proven it, that some of the MV ES we usually see is actually due to bullet mass variation. If so, a lower mass bullet will have a faster MV but also a lower BC. The two effects may cancel each other out to a large extent, resulting a tighter dispersion at long range than one would expect from MV variation alone.

    It might be a good idea to track your bullet mass. If mass varies more than +/-0.3 gr, then it might be a noticeable effect, even if it's small. Otherwise, I think it's negligible.

    People have probably proven or disproven this hypothesis already, but I can't recall seeing anything recently about it.
     
    Last edited: Jun 10, 2015
  9. Wedgy

    Wedgy Well-Known Member

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    I was getting some uneven bullet seating pressures that I think was from some Imperial wax on the inside of the neck after turning even though I cleaned them in the ultrasonic(all other factors in the brass and bullets being the same). If it doesn't seat with the same pressure as the rest then "something" is different and it won't release the same so that round gets pulled and started over. Switching to a Magnetospeed got rid of a lot of headaches. I look at ES not SD(matter of opinion). A tenth of a grain may be ok for a 338. Keep trying to eliminate the variables.
     
  10. Greyfox

    Greyfox Well-Known Member

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    With high ES/SD, given consistent components and procedure, I will try a primer change first, then go to a powder change. I agree with a prior comment about a filled case frequently giving lower ES then partially filled cases. I strive for ES under 15 FPS.
     
  11. woods

    woods Well-Known Member

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    Seating depth does it for me

    [​IMG]

    .015" off - ES 31 fps, SD 11.67 fps, velocity 3209 fps
    .030" off - ES 31 fps, SD 11.70 fps, velocity 3200 fps
    ,045" off - ES 23 fps, SD 9.80 fps, velocity 3186 fps
    .060" off - ES 8 fps, SD 4.00 fps, velocity 3176 fps
    .075" off - ES 27 fps, SD 11.40 fps, velocity 3170 fps
    .090" off - ES 52 fps, SD 31.70 fps, velocity 3156 fps
     
  12. bruce_ventura

    bruce_ventura Well-Known Member

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    Damn that's a nice trend. Unfortunately my rifle won't group under 1" unless the bullet is on the lands.
     
  13. 338edge

    338edge Well-Known Member

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    Try using grafight on the neck of the case before seating your bullet. Also as others have said try changing primers.
     
  14. milo-2

    milo-2 Well-Known Member

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    A primer change may help here. I've found doing a ladder-ocw test you'll find what pressure zone your rifle likes and ES & SD numbers just come together. If you run the test in .3gr increments and you like a set of numbers, work both ways from it in .1gr charges and it should work.