Reloading For Accuracy

     If you haven't read through the case preparation for accuracy page, it can be found here:
Case Prep For Accuracy

     Now that your cases are prepped, it's time for primers, powder and bullets.  Again, we need to start with the rifle first.  To find your bullet seating depth, you will need an Over All Length gauge and a modified case. The point of this is to seat your bullets so that it is sitting as close to the rifling as possible.  .002-.001 inches from the rifling is recommended, though some like it right to the rifling.  Put the bullet you plan to use in the modified case and attach it to the OAL gauge.  The picture below is a .308 modified case on the end of a Hornady OAL gauge with an A-Max bullet.
     Remove the bolt and slide the case into the chamber.  Press the rod on the gauge so that the bullet seats up to the rifling.  You just need light pressure, then lock the rod in place.  You now have a cartridge with a bullet seated to get your measurement using a bullet comparator.  Insert your comparator in your calipers, close, and zero.
     Next, use the comparator to get a measurement on your modified case.  There is a cut out in the OAL gauge so that the caliper will fit in there for a proper measurement.  Once you have this, set your bullet seating gauge to seat bullets .001 (or your desired seating) less.  Note that this measurement will only be good for this type of bullet.  If you change brands, shape, or weight, you will have to measure again.
     Now, a note on your dies.  If you are doing all of this for accuracy, don't skimp on the dies.  You are going to want high quality competition dies.  They are significantly more expensive than others, but are going to be necessary for squeezing out every last bit of accuracy.  Redding competition dies are a good example.  RCBS makes some good competition dies as well.

     When it comes to primer seating, you will probably want to use a hand tool.  Using a hand priming tool lets gives you greater sensitivity to seating.  You want the primers to be fully seated, but not smashed up against the pocket.  You will develop a feel for a properly seated primer.

     Powder is going to be weighed for every case.  Pour your powder and trickle up to the desire weight.  It is time consuming, but you want the absolute best consistency in powder measure possible.  There is that word again, consistency.  Every single charge must be weighed.  As a side note on powder; When it comes to load development, I start low and make about 20 rounds, increasing the powder charge by .2 grains for each batch, until I get to max charge.  Then each batch is fired so I can compare them for accuracy and pick a powder charge.  Max load is not always more accurate and every rifle is a little bit different.  You will have to do some testing at the range to figure out what your rifle likes.  While you can go by chronograph data, consistent FPS does not always make for the most accurate load.  It certainly helps, but what the groups on target tell you is most important.   Check the cases for pressure signs as well to ensure you are not getting dangerous pressures.

     Now you can go back to seating the bullets with your newly set die.  Once they are seated, take final measurements again.  If you are so inclined, you can sort them by consistency in measurements and use the "odd-balls" for practice.  Really, there should be no odd-balls if you have been picky up to this point.  Record all of your load data in a journal for future reference.

     Reloading for accuracy is much different than loading for volume.  It is more time consuming and expensive.  Developing the most accurate loads possible is part of the fun of hand loading.

   

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