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Handloading is the process used to create firearm cartridges by hand versus those put together en masse and sold commercially, generally in packages of 6 to 50. When previously fired cases are used, the process is often called reloading. Generally only boxer primed cases (see internal ballistics) are reloaded, though there are exceptions.

Reasons for handloading

The most common motivations for handloading cartridges are increased accuracy and cost savings, though handloaders may sacrifice one for the other. Reloading fired cases can save the shooter a significant amount of money, as the case is usually the major cost of a cartridge. The handloader can also create cartridges for which there are no commercial equivalents, such as wildcat cartridges. Collectors of obsolete firearms often have to handload since many obsolete cartridges are no longer produced. Hunters may desire cartridges with specialized bullets. Target shooters seek optimum accuracy. Many handloaders customize their cartridges to their specific gun. This is usually in the pursuit of accuracy, though it can also lead to an increase in case life. For these specialty applications, cost is usually not a primary motivator, and such cartridges may cost more than commercial ones.

Variables in the reloading process

The handloading process can realize increased accuracy through improved consistency of manufacture. Each cartridge loaded can have each component carefully matched to the rest of the cartridges in the batch. Brass cases can be matched by volume and weight, bullets by weight and concentricity, powder charges by weight. Primers also play a role in accuracy and consistency, but the handloader usually has no ability to manufacture these, so the handloader is limited to experimenting with different primers available commercially. In additon to these items that are considered critical, the equipment used to assemble the cartridge also have an effect on its performance; dies used to size the cartridges can be matched to a given rifle's chamber, high precision scales can give more consistent and accurate measures of powder.

Atypical handloading

It is typically agreed that rimfire cartridges (e.g. .22 Long Rifle) are not handloaded, although there are some shooters that unload commercial rimfire cartridges, and use the primed case to make their own loads, or to generate speical rimfire wildcat cartridges. These cartridges can be remarkably labor intensive to produce, and the process of unloaded the live rimfire cases can be dangerous, since any crushing of the thin brass rim can ignite the primer and cause the case to explode.

Berdan primers, with thier offcenter flash holes and lack of self contained anvil, are more difficult to work with than the easily removed Boxer primers. The primers may be punctured and pried out from the rear, or extracted with hydraulic pressure. Primers must be selected carefully, as there are more sizes of Berdan primers than the standard large and small pistol, large and small rifle of Boxer primers. The case must also be inspected carefully to make sure the anvil has not been damaged, because this could result in a failure to fire.

Materials required

• Cases or shotshell hulls. For shotshells, plastic or paper cases can be reloaded, though plastic is more durable. Steel and aluminum cases do not have the correct qualities for reloading, so a brass case is essential.
• Gun powder of an appropriate type. Generally, handgun cartridges and shotshells use faster powders, rifle cartridges use slower powder.
• Bullets, or shot and wads for shotshells.
• Primers

Reloading process

The operations performed when handloading are:

• Case inspection (reloading only)
• Remove the fired primer (reloading only)
• Ream or swage crimp from primer pocket (reloading military cases only)
• Resize the case (reloading only)
• Expand the neck to accept the bullet
• Seat a new primer
• Add a measured amount of powder
• Seat the bullet in the case
• Crimp the bullet in place (optional)
• Cartridge inspection

When previously fired cases are used, they must be inspected before loading. Cases that are dirty or tarnished are polished in a tumbler to remove oxidation and allow easier inspection of the case. Cracked necks, non-reloadable cases (steel, aluminum, or Berdan primed cases), and signs of head separation all are reasons to reject a case. Cases are measured for length, and any that are over the recommended length are trimmed down to the minimum length. Competition shooters will also sort cases by brand and weight to ensure consistency.

Removal of the primer, called decapping, is usually done with a die containing a steel pin that punches out the primer. Berdan primed cases require a different technique, either a hydraulic ram or a hook that punctures the case and levers it out from the bottom. Military cases have crimped in primers, and decapping leaves a slight ridge that inhibits seating a new primer. A reamer or a swage is used to remove this crimp.

When a cartridge is fired, the internal pressure expands the case to fit the chamber. To allow ease of chambering the cartridge when it is reloaded, the case is swaged back to size. Competition shooters, using bolt action rifles which are capable of camming a tight case into place, often resize only the neck of the cartridge, called neck sizing, as opposed to the normal full length resizing process. Neck sizing is only useful for cartridges to be re-fired in the same firearm, as the brass may be slightly oversized in some dimensions for other chambers, but the the precise fit of case to chamber will allow greater consistency and therefore greater potential accuracy. Semiautomatic rifles and rifles with SAAMI minimum chamber dimensions often require a special small base resizer, that sizes further down the case than normal dies, and allow for more reliable feeding.

Once the case is sized down, the inside of the neck of the case will actually be slightly smaller than the bullet diamter. To allow the bullet to be seated, the end of the neck is slightly expanded to allow the bullet to start into the case. Boattailed bullets need very little expansion, while unjacketed lead bullets require more expansion to prevent shaving of lead when the bullet is seated.

Priming the case is the most dangerous step of the loading process, since the primers are pressure sensitive. Seating a Boxer primer not only places the primer in the case, but it seats the anvil of the primer down onto the priming compound, in effect arming the primer. A correctly seated primer will sit slightly below the surface of the case. A primer that protrudes from the case can cause a number of problems; it will tend to hang up when feeding, and the anvil will not be seated correctly so the primer may not fire when hit by the firing pin. Berdan primers must also be seated carefully, and since the anvil is part of the case, the anvil must be inspected before the primer is seated.

The quantity of gunpowder is specified by weight, but almost always measured by volume. A powder scale is needed to determine the correct volume setting for the powder measure, as loads are specified with a precision of 0.1 grain (0.007 grams). Competition shooters will generally throw a slightly underweight charge, and use a powder trickler to add few granules at a time to the charge to bring it up to the exact weight for maximum consistency. Special care is needed when charging large capacity cases with fast burning, low volume powders. In this instance, it is possible to put two charges of powder in a case without overflowing the case, which can lead to dangerously high pressures and a significant chance of bursting the chamber of the firearm. Non-magnum revolver cartridges are the easiest to do this with, as they generally have relatively large cases, and tend to perform well with small charges of fast powders.

Competition shooters also often sort bullets by weight, often down to 0.1 grain (0.007 grams) increments. The bullet is placed in the case mouth by hand, and then seated with the press. At this point, the expanded case mouth is also sized back down. A crimp can optionally be added, either by the seating die or with a separate die. Taper crimps are used for cases that are held in the chamber by the case mouth, while roll crimps may be used for cases that headspace on a rim or on the cartrdige neck. Roll crimps hold the bullet far more securely, and are preferred in situations, such as magnum revolvers, where recoil velocities are significant. A tight crimp also helps to delay the start of the bullet's motion, which can increase chamber pressures, and help develop full power from slower burning powders (see internal ballistics).

Equipment

The basic piece of equipment for handloading is the press. A press is a device that uses compound leverage to push the cases into the dies that perform the loading operations. Presses vary from simple, inexpensive single stage models, to complex progressive models that will eject a loaded cartridge with each pull of a lever, at rates of 10 rounds a minute.

Presses

Single stage presses are the simplest. They perform one step on one case at a time. When using a single stage press, cases are loaded in batches, one step per batch at a time. Batches should be kept small, about 50 cases at a time, so that a batch is never left in a partially completed state. Once a case is primed, it should be finished as soon as possible, since high humidity can degrade the primer.

Progressive presses handle several shells at once, with each pull of the lever performing a single step on all the cases at once. Progressive presses hold all the dies needed, plus a powder measure and a primer feed, and often also include an additional station where the powder levels are checked, to prevent over or under charges. Progressive presses also often feature case feeds that will hold hundreds of cases to be loaded, and all the user has to do is hold the bullet in place over the appropriate case mouth, and pull the lever.

Shotshell presses are a special case, and are generally a single unit that handles all functions. Shotshell reloading is similar to cartridge reloading, except that instead of a bullet, a wadding and a measure of shot are used, and after loading the shot, the shell is crimped shut. The shotshell loader contains stations to resize the shell, measure powder, load the wad, measure shot, and crimp the shell. Due to the low cost of modern plastic shotshells, and the additional complexity of reloading fired shells, shotshell handloading is not as popular as cartrdige handloading.

Dies

Dies are generally sold in sets of two or three dies, depending on the shape of the case. A three die set is needed for straight cases, while a two die set is used for bottlenecked cases. The first die of either set performs the sizing and decapping operation. The middle die in a three die set is used to expand the case mouth of straight cases, while in a two die set the entire neck is expanded as the case is extracted from the first die. The last die in the set seats the bullet and applies a crimp. Special crimping dies are often used to apply a stronger crimp after the bullet is seated, and progressive presses often use an additional "die" to meter powder into the case (though it is arguably not a real die as it does not shape the case).

Shellholders

A shellholder, generally sold separately, is needed to hold the case in place as it is forced into and out of the dies. The reason shellholders are sold separately is that many cartriges share the same base dimensions, and a single shellholder can service many different cases. Shellholders are also specialized, and will generally only fit a certain make of reloading press, while dies are more standardized and will fit a wide variety of presses.

Scale

A precision scale is a near neccessity for reloading. While it is possible to load using nothing but a powder measure and a weight to volume conversion chart, that greatly limits the precision with which a load can be adjusted, and the variation inherent in measuring by volume means that maximum loads should be avoided. With a powder scale, an adjustable powder measure can be calibrated more precisely for the powder in question, and spot checks can be made during loading to make sure that the measure is not drifting. With a powder trickler, a charge can be measured directly into the scale, giving the most accurate measure. A scale also allows bullets and cases to be sorted by weight, which can increase consistency further. Sorting bullets by weight has obvious benefits, as each set of matched bulllets will perform more consistently. Sorting cases by weight is done to group cases by case wall thickness, and match cases with similar interior volumes. Military cases, for example, tend to be thicker, while cases that have been reloaded numerous times will have thinner walls due to brass flowing foward under firing, and being later trimmed from the case mouth.

Priming tool

Single stage presses often don't provide an easy way to prime cases. Various add-on tools can be used for priming the case on the down-stroke, or a seperate tool can be used. Since cases loaded with a single stage press are done in steps, with the die being changed between steps, a purpose made priming tool is often faster than trying to integrate a priming step to a press step.

Powder measure

Beginning reloading kits often include a weight to volume conversion chart for a selection of common powders, and aset of pwoder volume measures graduated in small increments. By adding the various measures of powder a desired charge can be measured out with a safe degree of accuracy. However, since multiple measures of powder are often needed, and since powder lots may vary slightly in density, a scale accurate to 0.1 grain (1/7000th of a pound, or .006 grams) is desirable. Both balance scales and electronic scales are available, and while electronic scales are easier to use (and generally have English to metric unit conversions) the balance scales can be more accurate for a skilled user, as they let the user discern differences of less than the stated accuracy of the scale.

Bullet puller

Like any complex process, mistakes in handloading are easy to make, and it's far better to be safe and re-do a questionable step than to hope thing will come out all right. A bullet puller is the answer to the question of what to do with the mistakes. Most pullers use inertia to pull the bullet; they are shaped like hammers, and the case is locked in place inside. A sharp blow on a hard surface will suddenly stop the case, and the intertia of the heavy bullet will pull it free of the case in a few blows. The bullet and powder are trapped in the bullet puller, and can be reused. Primers are a more problematic issue. If a primer is not seated deeply enough, the cartridge (if loaded) can be pulled, and the primer re-seated with the seating tool. Primers that must be removed are best deactivated first--either firing the primed case in the appropriate firearm, or soaking in oil will acheive this (oil is used because most primers are designed to be water resistant).

Safety/Caveats!

• Wear eye protection.
• Keep face clear when priming--primers can throw particles at high velocity and penetrate the skin.
• Keep heat sources away, and NEVER smoke when reloading
• Store powder in loose container. Unconfined powder burns, confined powder will explode.
• Dispose of unknown or contaminated powder.
• Damaged or contaminated primers should be soaked in oil to deactivate them before disposing.
• Store primers in factory packaging, to protect them from impact and reduce the risk of chain reactions if one should detonate.
• Keep work area clean. A dirty reloading area means that dropped components can become contaminated with oil or dirt.

Accuracy tips

Precision and consistency are key to developing accurate ammunition. Careful sorting of components is the first step to this; bullets should be sorted by weight, and each lot of matched bullets should be stored separately and marked with the exact weight. Each lot of cases should start new, purchased as a single lot, and stay together as they are reloaded. Powder for a lot of ammunition should come from a single can, and primers should come from the same box. If a powder measure is used, the same person should measure each load, using the same technique for every measure, since differences in technique can result in the powder packing slightly differently in the measure. If an analog scale is used, then the same person should perform all measurements, in the same light and from the same position--digital scales remove the variance in observation, but they also remove the ability to push the limits of the scale's precision. The positions of the dies and the adjustments of the powder measure should be checked periodically during loading, to make sure that the adjustments are not drifting. Carefully following these techniques will make each cartridge as much like every other as possible, and this is one of the fundementals of accurate shooting.

Tuning load to gun can also yeild great increases in accuracy, especially for standard, non accurized rifles. Different rifles, even of the same make and model, will often react differently to the same ammunition. The handloader is afforded a wider selection of bullet weights than can readily be found in commercially loaded ammunition, and there are many different powders that can be used for any given cartridge. Trying a range of bullets and a variety of powders will determine what combination of bullet and powder gives the most consistent velocities. Careful adjustment of the amount of powder can give the velocity that best fits the natural harmonics of the barrel (see accurize and internal ballistics). For ultimate accuracy and performance, the handloader also has the option of using a wildcat cartridge; wildcats are the result of shaping the cartridge and chamber themselves to a specific end, and the results push the envelope of velocity, energy, and accuracy.

• Ammunition