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How do you separate your cases? Weight or Headstamp?

Discussion in 'Handloading and Reloading' started by Lovesbeer99, Oct 21, 2011.

  1. Lovesbeer99

    Lovesbeer99 Participating Member

    Sep 27, 2006
    In the past I've separated by headstamp but yesterday I started weighing cases and even within headstamp I had weight diferrences as much as 2 grains. I even had cases weigh the same but with different headstamps. The question is how much of a difference is accepatble? I was wieghing LC, PMC and RP. Note that this was after cleaning, resizing, trimming, and primer pocket cleaning.

    I know that's a broad question but let's try to keep it somewhere between those whos shoot anything and those whoe shoot extreme benchrest. What would a varmint shooter, or High Master service rifle shooter do?
  2. 243winxb

    243winxb Mentor

    Jul 7, 2004
    Hopewell Big Woods
    Brass Prep & Weight & Chamber Volume

    Buy new brass of the same lot/brand, prep, load and shoot it. Or sort brass by .1 gr for rifle for best benchrest accuracy. 2gr is not bad as most 243win new factory brass will go around 3gr, rem., win., in lots of 100. You will get flyers that open the group using brass that has a 3gr spread. When you get 2 brass that are the heavest & 3 at the lightest weight, you can see the difference. A rifle chamber has a volume running from the bolt face to where the bullet seals the bore. Any mass of a different weight put into that volume changes pressure. Even with 45 acp match grade Bullseye guns, accuracy can be poor with mixed range brass when your trying to group into 3" or smaller @ 50 yds.
  3. Hangingrock

    Hangingrock Participating Member

    Mar 10, 2010
    To a certain existent it would depend if one is a short course or long course shooter in Highpower rifle competition. I use to purchase processed and primed brass from River Valley Ordinance that was mostly Mil-Spec and used it at the 200yd & 300yd lines then at the 500yd or 600yd lines new commercial brass. The commercial brass I did prep. In the past few years I’ve done mostly short course shooting which in my opinion brass prep isn’t required except for trimming to length on a Gracey.
  4. loadedround

    loadedround Senior Member

    Feb 18, 2006
    Valley Forge, Pa
    Both pistol and rifle by manufacturer (headstamp)....was never into benchrest shooting.
    Last edited: Oct 21, 2011
  5. Walkalong

    Walkalong Moderator

    Nov 20, 2006
    Both if you are shooting a gun that can tell the difference.

    General shooting? Sort rifle by headstamp. Don't worry about pistol, mostly.
  6. bds

    bds Elder

    Jan 10, 2010
    Northwest Coast
    My experience has been similar. Keep in mind that unless they are once-fired brass, depending on how many times they have been resized and trimmed, you are going to see variations in case weight. When I bought once-fired .308 cases, I weighed all of them to sort thicker walled less internal volume military cases from thinner walled more internal volume commercial cases. What I found was variations in case weight of several grains even within the same headstamp cases. Between commercial and military cases, weights ranged between 165 to 179+ gr.

    Initially, I loaded and range tested from the same weight cases (within 1 gr) but did not find enough differences in shot groups when the case weight variations were within a few grains. I still separate military cases from commercial cases, but OK with case weight variations within several grains post resizing and trimming.

    I am not a benchrest shooter, but will "glean" from their practices to produce more accurate loads without going to extreme means. :D

    Here are some article excerpts from The Riflemans Journal website, which is dedicated to benchrest shooting, that talk about case prep for precision rifle shooting - http://riflemansjournal.blogspot.com/2010/10/cartridges-loading-308-for-palma.html

    Last edited: Oct 21, 2011
  7. gamestalker

    gamestalker member

    Sep 10, 2008
    SW Arizona
    If your going to sort brass for the purpose of accuracy, weight is a more important factor over head stamp.

    The reason for sorting brass is to attain consistency primarily of internal dimension / capacity which in turn helps to regulate internal pressures. But if your really serious about attaining consistency it is best, and probably easier as well, if you use the same lot # of the same head stamp, every case trimmed to exact same length.
  8. amlevin

    amlevin Active Member

    Jan 15, 2007
    NW Washington
    If I have nothing to do, I will sort by headstamp and then weigh cases. I make sets of 50 and box for future loading. I don't do this until the cases are cleaned, neck sized, trimmed, flash hole deburred, and primer pockets uniformed. Anything that will take metal from the case is done before weighing for obvious reasons.

    On cleaning, I also use Stainless Steel pin media as it cleans the inside of the case as well. Unlike the corncob or walnut shell media it doesn't leave any residue from previous firings behind which have varying weights. Even if the amount is small, it is there and there is no way of knowing if it's uniform from case to case.

    When sorting a large quantity of brass it is fairly easy to find 50 pieces that are +/- .1 grain, even sometimes the same weight with no variance other than the scale accuracy.

    If you really want EXACT cases, don't weigh them, but measure their volume of water. Weigh the case, then fill it with water and weigh again. Record the amount of change in weight which will be the water capacity in grains. This removes all question as to volume.

    If merely weighing how do you know that all those cases of the same weight have the same volume??? It's only an assumption where water weight becomes less a guess and more an absolute. The question is whether the time really makes for more accuracy or if one has passed out of the effort/reward zone.
  9. Kevin Rohrer

    Kevin Rohrer Active Member

    May 29, 2010
    Medina, Ohio USA
    Individual rifles get specific makes of brass assigned to them. All other brass gets bagged together until I can find a use for them.

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