The Foundation To An Accurate Load…..Brass

Written by Sierra Bullets Ballistic Technician Paul Box

We all know that it takes many things in the making of an accuracy load. We have to have a good barrel. It has to be fitted to the action proper. A good chambering job. The bedding of the rifle’s action has to be good, on and on, but even the best built rifle will not shoot to its’ potential with bad brass.  Below are some of the steps I recommend to prep new brass.

New Shiny Cases
Weigh the Cases

When I get a new lot of 100 cases, the first thing I do is weigh them. If I’ve never worked with this caliber before I will weigh 20 cases and write the weights down as I go along. Then I add the weights of all 20 up and divide by 20 to get an average. If this is a cartridge in the 22-250 thru the ’06 size, then I use 1.0 gr. above and 1.0 gr. below the average case weight and keep everything in this 2.0 gr. bracket. Cases in the 300 Win Mag size I go 1.4 grs. above and below the average and smaller cases like a .223 I use .7 of a gr. above and below. If you want to use tighter tolerances than this, that is fine, but I’ve found that very well built varmint guns will shoot down in the high .2’s and low .3’s with this method.

Deburr the Flash Hole

The next thing I do is deburr the flash hole. American made brass has a flash hole that has been punched and typically has a burr on the inside. Norma and Lapua have drilled flash holes and usually don’t have any burr or only a very slight one. I still deburr these as well and give them a slight chamfer at the same time. I’ve never been able to prove this, but I’ve always thought this little chamfer would more evenly spread the flash from the primer into the powder column and improve ignition. Besides, it makes me feel warm and fuzzy.

Uniform the Primer Pockets

Next I uniform the primer pockets. Brass that have a punched flash hole will be the worst, but they all will be concave in shape. A uniforming tool will cut them flat on the bottom and allow a primer to be seated perfectly flat giving all the energy from the firing pin to set the primer off rather than final seat it the last .001-.002″.

Measure the Case Necks

Next I measure the case necks and compare the difference between the thick and thin side. What I’m looking for is a difference of .001″ or less. Cases that are between.001 and .002″ are set aside to be neck turned. The more uniform the case necks are, the easier it is for your seating die to seat a bullet in better alignment with the case body.

Brass that has been prepped through these steps will give your rifle the best chance to deliver the accuracy it is capable of.

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28 Responses to The Foundation To An Accurate Load…..Brass

  1. Pingback: The Foundation To An Accurate Load…..Brass | Rifleman III Journal

  2. firstriverbend says:

    Great information. I would add in my experience different brands will also work better or worse in different firearms, especially rifles. I have had some rifles which showed little to no preference, just needed good prep and some which showed a great deal of preference no matter how much prep was done.


  3. Sounds like a good idea for my recycled brass even though I bought it new & loaded.


  4. David Ruppel says:

    Good article! I need to start doing all those steps. I do everything else to prep my Brass I might as well go all the way and squeeze a little more accuracy out of my rounds. I guess I need to buy some more tools.
    None of my Brass just sits under the bench collecting dust. I use it til it’s time to throw it away. And even then I save it to sell to the scrape yard. I take that cash and buy more Brass! Kind of like the circle of life! LOL

    Liked by 1 person

  5. Paul Box says:

    I know what you mean Dave. Only a reloader would look for fifteen minutes for one piece of brass that he dropped.

    Liked by 1 person

  6. Davis says:

    Weigh the case last to get better idea of uniformity , that is how the bench rest shooters I knew did it.


  7. Paul Box says:

    Honestly, I prefer to do it first because why do all that work on brass that’s already outside your tolerance ?

    Liked by 1 person

  8. Daryl Davis says:

    I can typically get about any rifle (with a quality tube) to shoot sub moa at 250 yards consistently by adhering to Mr. Box’s regimen with the additional use of a concentricity jig to check bullet run out after seating and siziing with only bushing dies to control neck tension. Sinclair as well as Hornady produce very accurate and inexpensive jigs for that, something I feel is absolutely necessary to consistently shoot sub moa at distance.

    It’s always been my philosophy that top quality components and tools are necessary for consistently accurate ammunition as well as a quality firearm.


  9. Stumpy says:

    I’am not a benchshooter,shoud I do this to my hunting rounds!


    • firstriverbend says:

      It really depends on how far you are shooting at game and how accurate your firearm is with what you are feeding it now.
      For myself, I have a number of different “what I need” rounds.
      For target shooting, I always want to see how small of a group I can make.
      For hunting, if it is squirrels and they are 2-3 hundred yards away, I need to be making pretty small groups. If it is deer that will be only 100-150 yards away, then the group does not need to be very tight. I have killed a lot of one shot deer with ordinary military rifles shooting around a 4-5 inch group at that range. Never had to track more than a few dozen yards at the most. Many just dropped in their tracks.
      Use to shoot squirrels with a 9mm Polish Radom, seldom missed and was just using 1948 surplus ammo.
      So decide what you need for accuracy, spend time at the range finding out how accurate the combination really is and decide. 🙂
      That is really the only way to determine how much work you need to put into each round.


    • Daryl Davis says:

      Stumpy, neither am I. While I do have a private range to work up loads and develop trajectories, I am first and foremost a hunter and recreational shooter. Having said that, my goal is one shot humane kills and to attain that at distance takes carefully built and accurate loads as well as a quality and consistent shooting platform.

      I’ve had some excellent teachers in the art of reloading. John Pierce for one and I’m like a sponge, I take in every word from a master and apply that to my loading regimen.

      My go to caliber is 7.62 x 54 (308 Winchester) and while some say it’s not a viable big game caliber, I say that properly loaded, in a high quality case like Lapua or Norma, sending a well designed pill with a low ballistic coefficient, a 308 is very capable of taking any North American game animal (elk included) at distances out to 500 yards and clean kill and smaller thin skinned game like Whitetails or antelope to 600 yards plus and clean kill.. I’ve done it in the past and I trust my loading skill and so do the guys I hunt with. I seem to wind up building loads, not just for myself, but for everyone I hunt with.

      The bulk of my hunting however, is here in Michigan at distances much less than 500 yards, mostly less than 150 yards but knowing my handloads are consistently accurate at 500 yards plus, just adds confidence to my shooting ability.

      For many years, I was a student of ‘Kentucky Windage’. Little did I know that with the proper optics and drop charts, you could actually dial your zero and be spot on. While I zero all my rounds at 200 yards, the drop chart affixed to the buttstock of my rifle and my rangefinder will give ma a fairly accurate trajectory and point of impact within the kill zone of the animal I’m hunting, to make that clean one shot kill at 100 yards or whatever I range an animal at.

      Of course factors like spin drift come into play at longer distances where prevailing winds are strong but for most shots less than 500 yards, that is inconsequential.

      Not to plug Sierra, but 75% of the pills I load are Sierra, long gun and handgun. I find the Game Kings to be consistent in weight and have consistent meplats (necessary for consistency round after round). My meplat uniforming mostly consists of uniforming the tips only.. I don’t touch the handgun pills at all. I also handgun deer here in Michigan using a S&W 44 magnum wheel gun and a Henry Chambered in 44, shooting 240 grain Sportsmasters, I consider them the ultimate close range under 75 yard deer round with tremendous expansion and knock down power.

      No matter what caliber you prefer, the basis for accuracy comes with careful handloading using the highest quality components available and taking your time to insure uniformity in every aspect of the loading regimen.

      I’m of the philosophy that I can make just about any platform shoot well, baring a mechanical issue and I’ve done it..

      Liked by 1 person

  10. David Dick says:

    You weigh a 20% sample of new cases and, presumably, do not use those that fall outside your tolerance. First question: do you then weigh the remaining 80% and keep only those that fall within the tolerance you established with the first 20%? If so, what use to you make of the unfortunate light and heavy cases. Second question: do you weigh again after deburring flash holes, informing primer pockets and neck turning? Those operations, collectively will remove some brass, therefore weight, and change the original tolerance standard you set. Does that weight loss have any bearing on meeting your objective?

    I thank you most kindly.


    • Paul Box says:

      The weight loss from all this brass prep doesn’t effect the tolerances that I keep them in. In cases that fall outside of my weight tolerance I keep and use them for dummy rounds, foulers etc.


  11. David Dick says:

    Make that “reforming” primer pockets. Keyboard malfunction.


  12. Bill Sliemers says:

    I am still shooting 168; 180; 190 that I bought when Sierra was in Santa Fe Springs, CA when they sold seconds in bulk at a very cheep price. Does Sierra still sell seconds?


  13. Ken James England says:

    I have followed Pauls advice for a few years, and it works, I only use Norma or Lapua brass with Sierra 55 gr Blitzking in my 223 & had fantastic success on rabbits & foxes at up to.. 300 yards,sometimes at night.
    Thank you Paul & Sierra
    Ken James England


  14. Camek says:

    Very fantastic and really exact points of intetest


  15. These are the exact steps that I was taught to use by the late “Doc” at Prairie Arms in Denver many years ago. That would be for first time brass as well as first reloaded factory. The one additional thing that I do is polish the inside of the neck. Especially on hot 22 caliber loads. Does it make a difference? It seems to when you are trying to hit a Prairie Rat as 500 plus! Great informative writing! Oh, and that brass that is outside weight criteria? I save it, and the next bag very well might have enough similar weight that I can load up a bunch of hunting ammo for my friends!

    Liked by 1 person

  16. Maulus says:

    Nice tips. Though the “223 I use .7 of a gr. above and below”.


  17. Ron says:

    The first thing I prefer to do is trim to length as I have noticed that the length of untrimmed cases varies often by several thousandths judging from what comes off the case mouth. I then proceed with weighing, averaging and sorting as you do.


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