RELOADING BASICS – Case Preparation

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You’ve bought a bunch of components, and you’re ready to start loading. But where do you begin?

This guide is a work in progress. For the overview and links to other chapters, click here.

Safety Inspections

Impending Case Head Separation
These grooves can be detected internally with a paper clip before they become visible on the case exterior.

Before you dump a bunch of work into your brass, it’s always a good idea to make sure you don’t have any cases that have any disqualifying features. Cracks in the neck and signs of case head separation (pictured above) must be discarded. Flattened primers or shiny case bodies near the case head indicate the last firing was hot or difficult to extract and warrant further inspection. Some deformation in the neck or shoulder can be fixed either during resizing or at the next firing, but I tend to err on the side of caution. One piece of brass is not worth an injury.

Optional Uniforming

Anyone can pull on a press and churn out some bulk ammo. If that’s what you’re looking for, you can probably work up a mid pressure load and plug away without sweating some of the smaller details.

But if you want to smoke that dime-sized group at 100 yards and begin learning to hit your targets with consistency out to 1000m and beyond, then you’re going to need to scrutinize things a bit more than your average reloader.

While typically unnecessary with pistol brass, you might consider sorting your rifle brass into lots based on weight. Most brass should have similar outside dimensions, especially after resizing (hopefully), but differences in brass thickness can impact the pressure your loads produce.

For example, imagine you have worked up a .308 Winchester load with a single lot of brass that is close max pressure. If you pick up some brass from a different manufacturer or even a different lot from the same manufacturer, or God forbid some range-pickup loosies and load them to the same charge, a reduction in internal capacity can cause the same charge to be over pressure.

Weight sorting can help reduce the likelihood of this happening.

If you really want uniform internal capacity, you should verify the internal capacity of the cases with water. This can be done by plugging the primer pocket, weighing the case, and then filling with water and reweighing to get a water-weight value. Repeat, compare, and sort. This is a time consuming process, but probably worth the effort if you’re intending to flirt with any max pressure loads, which you do at your own risk.

You may also optionally uniform the primer pocket and debur the flashhole at this stage. There are simple tools available for this that can be mounted in a drill chuck or used as hand tools. This ensures consistency in primer seating depth and in primer ignition of the powder charge.

If any of your brass has crimped primer pockets, these should be identified, separated, and swaged. Dillon makes a bench mounted tool for this: Super Swage 600.

Case Cleaning

Used brass should be cleaned. Putting that grime back in your chamber adds a variable, and if you’re loading for accuracy, you’re treating every load as an experiment and trying to minimize the number of confounding variables in play.

Cleaners are broadly categorized as those that vibrate the cases within a dry cleaning media (usually corncob or crushed walnuts – lizard terrarium bedding from the pet store is a well known cheap option here) and those that tumble the cases within a water filled container, polishing them with steel media. The latter will get them looking brand new, but you’ll need a drying process and you’ll need to make sure no steel media gets left behind inside the cases, primer pockets, or flash holes.

There are also ultrasonic cleaners available, but I have no experience with them and therefore won’t comment on their use.

Decapping and Resizing

Now begins the actual loading process. Whether used or factory new, you will want to resize the brass in your press. Your sizing die will probably decap (remove the primer) from the primer pocket of any used brass simultaneously.

This presents your first question of process-sequence. If you clean your brass before resizing and decapping, you will keep any gunk removed during the cleaning process from getting inside your dies. But your primer pocket will not be cleaned and will be dirty when the primer is decapped.

One solution, though time consuming, is to first use a die that decaps without resizing. The inside of the die won’t come into contact with the brass as the primer is pushed out, and you can then clean the brass fully.

When using this approach, cleaning media can sometimes become lodged within the primer pocket.

Another approach is to clean, decap and resize, and then use the aforementioned primer pocket uniformer to clean out the pocket.

For most reloaders, dirty primer pockets probably have a negligible effect. But for the meticulous, these approaches may be helpful.

As mentioned in the previous chapter, there are two options for resizing your brass. But the short story is you should full length resize. Here’s the breakdown.

Full Length Resizing

You want your brass to last as long as it can reliably be reloaded without case head separation, neck cracking, or any other catastrophic failure, and you want your firearm to reliably and consistently close the bolt with the case in the chamber with little resistance.

In order to achieve both of these goals, you cannot resize the neck alone, but you also do not want to over resize the case. This is where certain headspace gauges and shoulder bump measurement tools can be extremely useful.

A bump of approximately .002″ in a bolt action firearm and .005″ in a semiautomatic firearm should give you a good balance of reliable bolt closure and extended brass life.

To set this bump, start with brass that has been fire formed to the chamber in question. Using a tool such as the LE Wilson Case Gauge Depth Micrometer paired with the correct case gauge, you place the brass within the case gauge and get a measurement on the micrometer of your fire formed brass by rotating the micrometer until it stops on the brass. You then adjust your die, checking the bump with the gauge until you get the desired setback. The $130 LE Wilson tool can be paired with any of their case gauges, which run $40. Whidden makes cartridge specific tools for this purpose at $64, so if you only need one or two, this is a cheaper option than the Wilson. Hornady also makes a inexpensive solution for this, but it must be mounted in a caliper to complete the measurement.

Neck Sizing

This type of die reshapes the neck for appropriate bullet tension using the same interchangeable bushings common in many full length dies but leaves the rest of the case untouched.

There is an argument to be made here that you achieve the absolute minimum work hardening of your brass reloading with this method. But you should consider that you will find more resistance as the round enters the chamber with brass sized in this way than if you bump the shoulder.

Consider whether brass life is more important than fast, reliable reloading between shots, especially with auto-loaders that might jam under such circumstances rather than simply require a bit of extra force to close the bolt handle.

Neck Tension

Modern reloading dies, particularly for bottleneck rifles cartridges, often use interchangeable bushings to properly set neck tension. The common recommendation is to set the neck tension at a value of .002″ though as with all things in reloading, experimentation can help you find values that perform better in your particular barrel. In order to determine the bushing size you need for your chosen tension value, you need to know the thickness of your case neck walls and the diameter of the bullet you want to seat. Multiply the neck thickness by two, add the bullet diameter, and subtract the desired tension for the final value.

But this doesn’t really tell the full story about the tension this imparts on the bullet. In most brass, case neck thickness varies from case to case, and is often not uniform across the full circumference of the neck. As the bushings are a measure of the outside diameter of the finished cartridge, a neck with irregular thickness will have different degrees of tension on different parts of the bullet.

The solutions to this problem, neck turning and neck reaming, will be discussed in the chapter on advanced techniques.

For now, know that you will need a range of bushings to accommodate different values in case neck thickness.

Additionally, as brass hardens, it can sometimes spring back more after resizing than it did when the brass was still soft, and will therefore need tighter bushings to achieve the same resizing outcome that wider bushings previously achieved. Calipers and micrometers are essential in checking these changes as your brass reaches the end of its life.

Another (better) remedy to be discussed in the advanced chapter is brass annealing, which helps keep the brass necks soft and extend their reloadable cycles.


Sinclair Hand Priming Tool

On most presses, this can be done immediately following the resizing action with a counter-press of the handle. This is the most efficient approach, but offers the reloader limited ability to feel the primer as it moves into the pocket. If you have military brass with crimped primer pockets, this may cause the primer to be crushed as it is inserted in the pocket.

Bench top priming tools and hand primers offer greater sensitivity, which in turn helps prevent crushing of primers in crimped pockets and a better ability to feel any resistance in primer seating for any other reason. A variety of options are displayed below.

Hand Primers

Lee Precision $24.99
RCBS $49.09
Frankford Arsenal $71.99
K&M Precision Shooting $75.85
Sinclair $119.99
21st Century Innovation $168.50

Benchtop Primers

RCBS $123.79
Forster Coax $125.95
Primal Rights $675.00

Yes, that is the correct price on the Primal Rights priming tool. I have never had my hands on one to feel what sort of priming action could be worth $675, but it’s there for those with money to burn.


LE Wilson Case Trimmer

Firing and resizing your brass will cause the brass to stretch overtime, increasing the overall length of the case. This must be corrected by trimming the brass back to the desired length. This step should always be done after you have resized the case, or the trimmed case may stretch again upon resizing.

After trimming, the case should be deburred and chamfered to ensure easy and consistent bullet seating and chambering of the finished round.


After confirming desired brass length with your calipers, the case preparation process has been completed and you are ready to add the powder charge.

To return to the guide’s Table of Contents, click here.

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