The Pursuit of Precision

by Admin | Last Updated: September 20, 2020

We have already covered the basics of reloading in our beginner’s guide, so if you are looking to find out how to get started reloading rifle ammo, that is the perfect place to start, here however we will take it further and progress to the more intermediate and advanced stages of reloading for precision rifle ammunition.

reloaded cartridges

Precision Reloading: The Goal

When shooting accuracy and precision is concerned, consistency and repeatability is the key. When developing your load, your aim is to find the optimal load for the lowest degree of deviance either up or down. The next step further is to lower the degree of deviation between two or three following cartridges, as this provides the consistency that delivers small groups and similar points of impact.

Yes, we know the first step is purely your own shooting technique, method and consistency and that this true precision reloading does not make much difference between a hit or a miss out to 300 yards, but further than that the difference does become critical.

Even if you only aim to shoot either accurately for your own want or for competitive reasons and it is below 300 yards, what the precision and accuracy gives you, if piece of mind. Knowing that if you miss or are off target, it is you and not the rifle or the cartridge. You also start to then see the difference wind and bullet drop calculation errors start to make. In the end, why do something if your aim is not to master it and do it well.

Because you only load new clean brass cases only once in their lifetime which could be between 10 to 14 reloads depending on how you look after them, this means that after that first time, you will always be using fired brass. So because of that we do include the steps to de-prime and clean the casings as well.

Depending on whether you are shooting with a custom made competition barrel and a factory standard rifle barrel, also if custom, how you gunsmith chooses to ream or size the chamber, will determine how much you need to resize your brass casing after each fire, or whether you fully resize, or just shoulder bump them. In general, the less you have to resize, or smaller the change to the casing size you make each time, will determine how many reloads you get out of your brass cases before they fail, as this will determine how much stretching and contracting of their size occurs each round.

In general, when we consider the Sporting Arms and Ammunition Manufacturers’ Institute (SAAMI) specifications for caliber casing and chamber sizes and dimensions, the factory standard chamber and cases need to be closer to the limits of each size. This is usually done in an effort to ensure compatibility for the general user. So if we look at a OEM factory rifle for instance, with it’s factory barrel, the chamber is usually manufactured on the upper spectrum of the SAAMI specifications, in an effort to try and ensure that most factory ammunition will fit in that chamber, and most custom loaded ammunition too. Now in contrast, when looking at factory ammunition, the casings and cartridges are usually manufactured at the lower end of the spectrum for SAAMI specification for that particular caliber, and this is done in an attempts to ensure that the ammunition will fit in most factory chambers from different manufacturers, as well as tighter custom rifle chambers.

So you can quickly see how using factory ammunition in a factory rifle, the brass cases expand quite a lot when shot, so thus when you resize them, if you want them to last longer, it is better to not size them down too far away from the chamber size which they have taken on during firing, so that the next time when that case is fired, is does not change a lot in size again.

Reload Therapy

Reloading ammunition, can be seen not only as an art form, but also as a form of therapy.

The fall of the powder into the scale bowl, the trickling of the kernels as the scale slowly climbs to the precise number desired, the seating of the bullet, the measuring with the caliper. Each step purpose driven with the goal of precision in mind.

When done well, with a well laid out reloading room or reloading bench, it can be very calming and pleasurable. To some, it is an immense stress relieving activity, putting one more into tune with your ammunition, and shooting, helping you focus on what is important for precision and accuracy. There is nothing in the world of precision shooting, as rewarding as seeing tiny little groups, and precise shots, with cartridges that you spent time on and reloaded carefully and thoughtfully yourself.


1. Decap primers

Using your reloading press with the die and decapping pin fitted, press out the spent primers from your brass casings. You could also get a specific hand deprimer tool if you prefer to do the depriming in front of the TV or do not have a die with decapping pin.

Now would be the right time to anneal the brass cases, if you wanted to. I recommend annealing them every 3 to 4 times that you have shot them. Follow our easy guide on how to anneal brass cartridge cases.

decap primers

2. Full Length Resize / Shoulder Bump

lubricate brass cases
case lube

Thoroughly lubricate the necks of your casings with suitable case lube, making sure not to spray it inside the casings. If you use enough case lube on each casing, the effort needed to resize them, or bump the shoulders back, will be less.

fl sizing

Now place the case into the shell holder on the reloading press, and pull the lever to press the full-length resizing die down onto and over the casing. Some people prefer to fully resize the casings after each fire, some after ever second or third fire, depending on how hard it is to close your rifle action when the cartridge is inserted into it.

full length sizing die

For well cut custom chambers, which locate the cartridge inside the chamber on the shoulder, it would be best to just shoulder bump the cases every reload, to about 1.5 – 2 thou (thousands of an inch), so they do not expand too much when fired each time. This will prolong the number of times you will be able to reload the same casings.

To shoulder bump the casings, you can either use a special or custom body die, or your normal full length sizing die, but with the expander ball removed. You then first press the die down onto the base of the press without a casing in it, screw it down until it touches the base, then simply screw it back out just half a turn. Lock it in place there, measure your case length from base to shoulder with a vernier fitted with a body comparator, then press the die down onto the case to bump the should back once, take it out and measure it again to see the difference. If the difference is less than 2 thou, or your desired difference, screw it down a little more and repeat the process until you reach a 2 thou difference. Lock your die into place there, and then shoulder bump all the remaining cases.

3. Clean Casings

From all the different methods and pieces of equipment available, we have found that the best way to clean used brass for reloading, is through tumbling with stainless steel media in a rotary tumbler. This method gets the cases clean both inside and out, and literally looking brand new if done and dried correctly.

cleaned brass casings

There is another small industry secret used by many bench rest shooters as the best way to clean used brass for reloading when they are in a hurry, or at the range. That is by spinning the case mounted on a chuck case holder or case holder and lock stud, on a cordless drill, with a cut strip of 3M Microfine wrapped around it, and then simply cleaning out the primer pocket with a primer pocket cleaner (not the reamer), then you reload and shoot. Simple as that.

4. Prime Casings

rifle primers

Although most modern reloading presses includes the ability to press primers into the cases, we much prefer hand priming tools for pressing the primers in. There are two reasons for that.

  1. The hand priming tool, presses primers into the cases very quickly so it speeds up your reloading process.
  2. The feel and feedback you get with a hand priming tool, helps to ensure that you consistently press the primers into the cases at the same depth. You also easily feel if any of your primer pockets are stretched as the primers slide in without any resistance whatsoever.
primed brass casings

Because we use a hand priming tool to press primers into the casing, this allows a person to be able to do so anywhere, not just at your reloading bench. So I usually press my primers into all my cases at nights whilst sitting in the lounge with my family watching TV.

5. Expand Necks / Neck Size

neck expander mandrel

Because the neck expander ball is removed from the full length sizing die or if using a body die, it does not have a expander ball, the necks then still have to be expanded or sized up to the correct size for the bullets to be able to fit into them, and be seated.

expand case neck

The reason we prefer a mandrel to expand the necks, is because they are so accurately concentric, so when expanding the necks with one, it pushes imperfections or uneven points inside the necks outwards, and helps to keep the inside of the necks concentric, ensuring even neck tension all the way round. These mandrels can also be ordered in various different sizes from 0.5 thou to 2 thou so you can choose the neck tension you prefer to have on you bullets.

6. Dispense Powder Charge

powder measure

There are a few different ways how to measure powder for reloading, either with a auto dispenser, auto trickler or normal powder dispenser. Most manual powder dispensers have a micrometer on them, so you can set the amount of gunpowder it should dispense with each pull of the lever.

These micrometers tend to differ from accurate to very inaccurate depending on the brand of dispenser, and then the type of gunpowder used. We tend to find the most inaccuracy when the using stick type gunpowder. The good part is that you only need to adjust the micrometer a few times throwing the first pour and weighing it until you find the correct setting that dispenses slightly under your target charge, and then leave it there, it should fairly consistently pour the same charge every time thereafter.

7. Weigh & Trickle Powder Charge

You them place your scale bowl with the powder charge in it on the scale, and then trickle a few more grains of gunpowder into it, until it is precisely at the charge you want to reach.

8. Pour Powder Charge

Pour Powder Charge

You then gently hold your funnel tightly on your casing, ensuring there are no gaps between the funnel and the neck of the casing, and then pour your powder through the funnel into the casing. Make sure all the gunpowder passes down the funnel into the case, and that there is no gunpowder stuck to the sides of the funnel. Aluminum reloading funnels tend to suffer less from static electricity build up and cling, than plastic funnels.

9. Seat Bullets

place bullet in casing

Place the case with powder charge into the shell holder of the reloading press, and then place a bullet into the casing.

bullet seating die

Making sure the bullet stays fairly straight, pull the lever on the reloading press, to lower the seating die onto the bullet, and press the bullet into the casing. Then lift up the lever again halfway, just so the seating die is off the bullet, rotate the bullet 180 degrees, and press it down again, just to ensure concentric bullet seating (maybe overkill with modern single stage reloading presses, but it just gives me piece of mind).

base to ogive measure

Measure your cartridge base to ogive length with your caliper and bullet comparator, to ensure the bullet is seated deep enough and the COAL of the cartridge is correct, then move on to the next cartridge. After measuring the first one or two cartridges, and provided that your press and die is set up tightly and correct, all cartridges thereafter should be the same length. Measure every 5th or 10th cartridge just to ensure the COAL and seating depth has still remained constant.

Congratulations, you have now reloading a batch of consistent precision cartridges ready to hit the range or hunting field with.


Reloading Tips

How to Store Gunpowder?

Knowing how to store gunpowder becomes important when humidity in the environment it is stored in rises. Humidity has a significant impact on the burn rate of gunpowder, and it is quite frustrating to a advanced reloader, if you go through all the trouble and care to load consistent precise cartridges, but the gunpowder proves inconsistent and causes your precision to fade because of moisture in it. Always ensure to keep your new gunpowder containers sealed until you need to open and use them. When opening your gunpowder containers, do so quickly, pour out only the rough estimated amount you are going to need in your powder dispenser and immediately put the lid back on and close it tightly. Check the storage room or cupboard for excessive humidity levels and if necessary, install a de-humidifier or place absorbent sachets in the storage cupboard. With these tips on how to store your gunpowder, you should not have much trouble with moisture build-up inside your gunpowder containers.

Neck Turning

Many custom built rifles have smaller or match chambers, which often are very tight fitting around the neck of the cartridge and require the reloader to neck turn the casings. Neck turning involves a process of cutting back or removing material from the outside of the case neck, so essentially making it thinner, with the goal of maintaining perfectly uniform neck thickness all around. Personally we have had custom competition rifles with tight neck chamber which require neck turning of the cases and custom competition rifles which do not. Whether or not you do it will depend on the chamber of your rifle. Be aware though that if you make the neck thickness of the casings smaller, you will also possibly get fewer reloads out of those same casings.


Reloading Terminology

Extreme Spread – ES

Once an accurate load has been developed for a given rifle, the main goal for precision becomes the Extreme Spread between all loads in a session and getting it as small as possible.

Standard Deviation – SD

Standard deviation refers to the variation in a set of data. So for load development and shooting purposes, it is the measure of how much the muzzle velocities of different shots in a string differ from the average or deviate from the average. The goal is to get the SD as close to 0 as possible, indicating consistency.

Moly Coating

Coating of bullet has been done for quite a few years by shooters for a number of reasons. The first reason moly coating of bullets is done, is in a effort to reduce neck tension and in doing so, get more consistent velocity out of each round fired, thus bringing down the extreme spread and in theory, also tightening up the groupings.

The second reason moly coating of bullets have been done, is in an effort to protect the barrel, and prolong barrel life. This is a valid concern with newer wildcat calibers that are known barrel burners. An extra 5-10% of barrel life, could easily mean a few hundred rounds extra per barrel, and over the course of 5 or 10 barrels, the cost and time saving quickly adds up.

Moly coating is somewhat of a older science, as it is generally found that hBN (hex Boron Nitride) coating is now more common and superior in friction reduction ability, clean handling ability, no moly build up or added wear in barrel. Some have found that hex-Boron, or Boron Nitride or Boron coating as some call it, have reduced their extreme spread in a string, while other like myself prefer it merely for barrel life extension.

The biggest benefit we have found with hBN coating bullets, it the accuracy and consistency of the first, cold-barrel shot, when usually you first have a flier (a shot that is slightly off from the rest) when shooting the first shot in a cold barrel after a day or two of not shooting the rifle. This is only a major concern in long range hunting or shooting, where the first shot counts and you cannot take a practice shot before that first counting shot.

Neck Tension

The neck tension of a cartridge, is the amount of tension or force with which a case neck holds on to the bullet. This is determined by how large the case neck is before the bullet is seated into it. The best neck tension is a hotly debated topic and varies from purposes of bench rest rifle shooting to hunting. Generally competition precision shooters and bench rest shooter prefer as little neck tension as possible, and hunters prefer more, as with hunting you usually keep the cartridges longer, and they can travel in and on the back of vehicles with you on rough roads, so you do not want the bullets to shift, move deeper in or even fall out of the casings.

What is equally important for both though, is having as uniform and consistent neck tension as possible on a batch of cartridges to ensure consistency.

Jump

The jump, is the distance a bullet travels when leaving a casing before making contact with the lands of the barrel rifling. After finding your sweet spot, or optimal barrel time during load development, start experimenting with different jumps to get your groupings smaller.

Pressure Signs

Pressure signs are signs on your casings that become visible when you start reaching your maximum pressure for the cartridge or caliber you are shooting, which starts getting dangerous. Common pressure signs are cratered primer strikes, primer pockets stretching so the black powder escapes around the primers (which is also usually accompanied with a different smell than normal shots), extractor pin mark on the head of the casing, and a rifle bolt that is hard to open after the shot. When you see any of these signs, stop shooting those cartridges immediately, and back off a little on your charge that you load in those cartridges.

Concentric Cartridges

Conentric cartridges, are cartridges which are straight, so when turning them, the casing or bullet is not tilted to one side or the other. Slight concentricity problems are not normally visible with the naked eye, and require a concentricity gauge to notice. Getting your cartridges as concentric as possible, helps improve consistency and so also precision.


Which is Better?

Digital or Bench Scale

This is a personal preference point, where the right answer will depend both on your own personal preference, and the external environmental factors of where you are reloading. We actually prefer both, whereby we use an accurate electronic scale for reloading during summer when the humidity is better and closer to 50%, or if we have a humidifier in the reloading room during the dry season keeping the room humidity close to 50%, as then the electronic scale is not affected by static electricity.

We also still have and often use our old school (but quite new as we bought it in 2019) bench scale when the static or other elements bother the electronic scale like mentioned in our static electricity post. So the choice is up to you and both deliver accurate results, however, just make sure you get a reliable and accurate reloading scale whether electronic or bench.

Powder Dispenser or Autotrickler

Save time, without sacrificing precision no matter the cost, the autotrickler will do so. Enjoy the therapy and art of precision reloading and measuring of powder for each charge, at the same time saving a bunch of money, then the manual powder dispenser and separate reloading scale is the way to go.

Single Stage or Multi Stage Press

As stated in our reloading press review, the multi stage reloading presses often sacrifice precise tolerance and alignment for the added functionality of having multiple stages which can quickly be switched between. However, as you can see on the modern single stage reloading presses we have reviewed and recommended there, the benefits of a multi stage press, have been overcome in the single stage presses that now offer quick-change blocks which allow you to change out dies and stages as fast as any multi stage press, and still keep the tight tolerances and alignment offered by a single stage press. So the single stage reloading press takes our vote here.

OAL or Ogive Measurement

cartridge overall length

Overall Length (OAL) or Cartridge Overall Length (COAL) of a cartridge is sometimes used to determine the length of a cartridge, in order to be able to repeat the load in future, however, with soft-points and hollow points, the inaccurate tolerances of the tip material cause them to vary, so this is not a good measure of length to work from. Also when determining the max cartridge length of your rifle, the OAL is also not the best, as the lands of the barrel (where the grooves and rifling starts) does not catch the tip of your bullet, but rather the first point where the diameter of the bullet is the full width for that caliber. This point is referred to as the ogive.

bullet comparator

Because various different weight and length bullets of the same caliber has different length from base to tip, is an overall length will still not provide for a consistent jump (the distance a bullet travels from the case to the lands of the barrel when fired) for different bullets, so the base to ogive measurement is much more accurate and consistent especially between different bullets. To measure the base to ogive length, you simply attach a bullet comparator to your caliper and re zero your caliper on the comparator.