Handloading

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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.

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[edit] Legal issues

Since many countries heavily restrict the civilian possession of ammunition and ammunition components, such as primers and gunpowder, handloading may be explicitly or implicitly illegal in these countries. Even without specific restrictions on powder and primers, they may be covered under other laws governing explosive materials. In addition, there are liability concerns that effectively restrict large organizations such as police departments from handloading.

[edit] Reasons for handloading

The most common motivations for handloading cartridges are increased accuracy and cost savings. Reloading fired cases can save the shooter a significant amount of money. 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 commercially produced. Hunters may desire cartridges with specialized bullets. Target shooters seek optimum accuracy. Many handloaders customize their cartridges to their specific gun, usually in the pursuit of accuracy. For these specialty applications, cost is usually not a primary motivator. As with any hobby, the pure enjoyment of the reloading process may well be the most important benefit.

[edit] Variables in the reloading process

There are three aspects to ballistics: internal ballistics, external ballistics, and terminal ballistics. Internal ballistics refers to the things which happen inside the weapon, before the bullet leaves the bore on firing. The handloading process can realize increased accuracy and precision through improved consistency of manufacture, by selecting the optimal weight and profile of the bullet, and tailoring the velocity of the bullet. Each cartridge re-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 bearing surface, powder charges by optimal selection and weight and optimal powder selection. In addition to these items that are considered critical, the equipment used to assemble the cartridge also have an effect on its uniformity/consistency and optimal shape/size; dies used to size the cartridges can be matched to a given rifle's chamber.

[edit] Atypical handloading

It is typically agreed that rimfire cartridges (e.g. .22 Long Rifle) are not hand-loaded, although there are some shooters that unload commercial rimfire cartridges, and use the primed case to make their own loads, or to generate special rimfire wildcat cartridges. These cartridges are highly labor intensive to produce. Berdan primers, with their off-center 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.

[edit] Materials required

  • Cases or shotshell hulls. For shotshells, plastic or paper cases can be reloaded, though plastic is more durable. Steel and aluminium cases do not have the correct qualities for reloading, so a brass case is essential (although nickle cases, while not as reformable as brass, can also be reloaded)
  • Gun powder of an appropriate type. Generally, handgun cartridges and shotshells use faster powders, rifle cartridges use slower powder. Powder is generally of the 'smokeless' type in modern cartridges, although on occasion the older 'black' powder more commonly known as 'gunpowder' may be used.
  • Bullets, or shot and wads for shotshells.
  • Primers

[edit] Reloading process

The operations performed when handloading are:

  • Case cleaning (optional)
  • Case inspection
  • Remove the fired primer (previously-fired cases only)
  • Ream or swage crimp from primer pocket (reloading military cases only)
  • Lubricate and resize the case
  • Measure and trim the case length (variable) (rarely required)
  • Clean the lubricant from the cases
  • 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 often polished in a tumbler to remove oxidation and allow easier inspection of the case. Cleaning in a tumbler will also clean the interior of cases, which is often considered important for handloading high-precision target rounds. Cracked necks, non-reloadable cases (steel, aluminium, or Berdan primed cases), and signs of head separation are all 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 in a process called obturation. 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 precise fit of case to chamber will allow greater consistency and therefore greater potential accuracy. Some believe that neck sizing will permit a larger number of reloads with a given case in contrast to full size resizing, although this is controversial. 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 allows 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 diameter. 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. The use of safety glasses or goggles during priming operations can provide valuable protection in the rare event that an accidental detonation takes place. 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 may cause a number of problems, including what is known as a slam fire which is the firing of a case before the action is properly locked when chambering a round. This may either damage the gun, and/or injure the shooter. A protruding primer will also tend to hang 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, especially in larger scale operations. 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 (6 mg). One grain is 1/7000 of a pound. Competition shooters will generally throw a slightly underweight charge, and use a powder trickler to add few granules of powder at a time to the charge to bring it to the exact weight desired 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 (6 mg) 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 cartridge 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).

[edit] 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.

[edit] 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 cartridge handloading.

[edit] 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 may apply 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).

Standard dies are made from hardened steel, and require that the case be lubricated, for the resizing operation, which requires a large amount of force. Carbide dies have a ring of tungsten carbide, which is far harder and slicker than tool steel, and so carbide dies do not require lubrication. Tapered carbide sizing dies such as the 9mm Luger and 30M1 Carbine require slight lubrication. Usually every fifth to tenth case as needed.

Modern reloading dies are standardized with 7/8-14 threads and are interchangeable with all common brands of presses, although older dies may use other threads and be press-specific. Dies for rifle bottle neck case usually are supplied in sets of 2 and sometimes 3. One manufacturer supplies a third die to apply a factory type crimp. This is an extra operation and is not needed unless the ammunition is used for hunting, a gun's magazine design requires crimped ammunition for safe operation, or for achieving the benefit of improved accuracy. The factory style crimp increases the shot start pressure causing a more uniform pressure curve.

Three dies are normally supplied for straight walled pistol cases. Most of these include a carbide sizing die. This is highly desirable because it eliminates the need to lubricate the case. A fourth die is becoming more popular for a factory style crimp and a post sizing operation. This greatly improves reliability.

[edit] 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 cartridges 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 modern dies are standardized and will fit a wide variety of presses.

[edit] Scale

A precision scale is a near necessity for reloading. While it is possible to load using nothing but a powder measure and a weight to volume conversion chart, this greatly limits the precision with which a load can be adjusted, and the variation inherent in measuring by volume means that maximum or near 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 bullets 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 forward under firing, and excess case length being later trimmed from the case mouth.

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. The simplicity of their construction is often reassuring when compared with the complexity of an electronic scale, which may not give any visible clues to defects or loss of calibration should that occur. Such reassurance is greatly valued when dealing with handloads, since the dangers posed by a badly-charged round are severe.

[edit] 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 separate 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.

[edit] Powder measure

Beginning reloading kits often include a weight to volume conversion chart for a selection of common powders, and a set of powder 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 (6 mg) is desirable.

[edit] 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 things 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 inertia 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 achieve this (oil is used because most primers are designed to be water resistant.)

[edit] 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 fundamentals of accurate shooting.

Tuning load to gun can also yield 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 and accuracies. 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.

While bullet weight is the most common factor in sorting bullets, it is not the only factor. Sorting by the length of the bearing surface (that area between the base of a flat-based bullet and the ogive, or the area above the base of a boattailed bullet and the ogive) often yields better performance in custom made rifles, particularly in competition firearms. The bearing surface of the bullet has a significant effect on a number of factors, including the energy required to swage the bullet into the rifling, the friction of the bullet in the bore, and most importantly, the freebore, or the distance the bullet travels before it engages the rifling. Measuring the bearing surface requires the use of a bullet comparator and micrometer combination. Sorting by this method ensures that the amount of bullet protruding from the case after being seated is consistent across the entire population of loads, which then ensures that the freebore is as close to identical as is possible. Varying freebore amounts invariably cause variations in chamber pressure which in turn affects velocity and downrange performance. This is particularly critical since the burn rate of smokeless powder is proportional to the pressure, so a slight change in pressure during the initial bullet movement can result in far greater changes as the burn continues. Sorting by bearing surface is generally done as a second step, first sorting by bullet weight (generally to within 0.1 grain (6 mg) in weight) and then sorting each weight category by bearing surface.

[edit] Cost considerations

Those who reload with the primary goal of maximizing accuracy or terminal performance may end up paying more per reloaded round than for commercial ammunition--this is especially true for military calibers which are commonly available as surplus. Maximum performance, however, requires the highest quality components, which are usually the most expensive. Reloaders who reload with the primary goal of saving money on ammunition, however, can make a few tradeoffs to realize significant cost savings with a minimal sacrifice in quality.

[edit] Bullets

While the case is usually the most expensive component of a cartridge, the bullet is usually the most expensive part of the reloaded round, especially with handgun ammunition. It is also the best place to save money with handgun ammunition.

For the truly frugal, the cheapest method of obtaining bullets is to cast them. This requires a set of bullet molds, which are available from a number of sources, and a source of known quality lead. Linotype and wheelweights are often used as sources of lead, and blended together to achieve the desired Brinell hardness. Cast bullets are also the cheapest bullets to buy, though generally only handgun bullets are available in this form. Some firearms, such as those using polygonal rifling like Glock and H&K, advise against the use of cast bullets. For shooters who would like to shoot cast bullets, aftermarket barrels are generally available for these models with conventional rifling, and the cost of the barrel can generally be recouped in ammunition savings after a few thousand rounds.

Soft lead bullets are generally used in handguns with velocities of 1000 ft/s (300 m/s) or lower, while harder cast bullets may be used, with careful powder selection, in rifles with velocities of 2000 ft/s (600 m/s) or slightly more. The limit is the point at which the powder gas temperature and pressure starts to melt the base of the bullet, and leave a thin coating of molten and re-solidified lead in the bore of the gun--a process called leading the bore. Cast lead bullets may also be fired in full power magnum handgun rounds like the .44 Magnum with the addition of a gas check, which is a thin zinc or copper washer or cup that is crimped over a tiny heel on the base of appropriate cast bullets. This provides protection for the base of the bullet, and allows velocities of over 1500 ft/s (450 m/s) in handguns, with little or no leading of the bore.

Most shooters prefer jacketed bullets, especially in rifles and pistols. The hard jacket material, generally copper or brass, resists deformation and handles far higher pressures and temperatures than lead. With the exception of a single company that offers a swaging machine designed to turn .22 Long Rifle cases into brass jackets for .22 caliber (5.56 mm) bullets, handloaders have no choice but to purchase pre-made jacketed bullets. The process of manufacturing a jacketed bullet is far more complex than for a cast bullet; first, the jacket must be punched from a metal sheet of precise thickness, filled with a premeasured lead core, and then swaged into shape with a high pressure press in multiple steps. This involved process makes jacketed bullets far more expensive on average than cast bullets. Further complicating this are the requirements for controlled expansion bullets (see terminal ballistics), which require a tight bond between the jacket and the core. Premium expanding bullets are, with match grade bullets, at the top tier in expense.

A more economical alternative was made available to the handloader in the 1980s, the copper plated bullet. Copper plated bullets are lead bullets that are electroplated with a copper jacket. While thinner than a swaged bullet jacket, the plated jacket is far thicker than normal electroplate, and provides significant structural integrity to the bullet. Since the jacket provides the strength, soft lead can be used, which allows bullets to be swaged or cast into shape before plating. While not strong enough for most rifle cartridges, plated bullets work well in many handgun rounds, up to about 1500 ft/s (450 m/s). Plated bullets fall between cast and traditional jacketed bullets in price.

While originally sold only to handloaders as an inexpensive substitute for jacketed bullets, the plated bullet has come far. The ammunition manufacturer Speer now offers the Gold Dot line, commercially loaded premium handgun ammunition using copper plated hollow point bullets. The strong bond between jacket and core created by the electroplating process makes expanding bullets hold together very well, and the Gold Dot line is now in use by many police departments.

[edit] Maximizing case life

Since the case is the single most expensive part of a loaded round, the more times a case can be re-used, the better. Cases that are loaded to a moderate pressure will generally last longer, as they will not be work hardened or flow under pressure as much as cases loaded to higher pressures. Use of moderate pressure loads extends the life of the case significantly. Work hardening can cause cracks to occur in the neck as the hardened brass loses its malleability, and is unable to survive swaging back into shape during the resizing operation. Rifle brass tends to flow towards the neck (this is why rifle brass must be trimmed periodically) and this takes brass away from the rear of the case. Eventually, this will show as a bright ring near the base of the cartridge, just in front of the thick web of brass at the base. If brass is used after this ring appears, it risks a crack, or worse, a complete head separation, which will leave the forward portion of the brass lodged in the chamber of the gun. This generally requires a special stuck case removal tool to extract, so it is very undesirable to have a head separation.

With bottlenecked cartridge cases, choosing the right sizing die can also have an impact. Full length sizing of cartridges is often thought to greatly shorten case life by work hardening the full length of the case, which can cause the case to split, although some studies show that the number of reloads possible with a case is essentially the same for either full length sizing as for neck sizing only. If the reloaded cartridges are going to be used in the same firearm in which they were previously fired, though, and if that firearm has a bolt action or other action with a strong camming action on closing, then full length resizing may not be needed. A collet neck sizing die can be used to size just the case neck enough to hold the bullet, and leaves the rest of the case unsized. The resulting cartridge should be able to fit back into the rifle that previously fired it, though the fit will be tight and require more force to chamber than a full length resized case. The use of a neck sizing die in conjunction with moderate pressure loads may extend the life of the case significantly by minimizing the amount of case that is work hardened.

Work hardening happens to all cases, even low pressure handgun cases. The sudden increase in pressure upon firing hits the brass like a hammer, changing its crystalline structure and making it more brittle. The neck of the case, if it becomes too brittle, will be incapable of standing the strain of resizing, expanding, crimping, and firing, and will split during loading or firing. While a neck split during firing is not a significant danger, a split neck will render the case incapable of holding the bullet in place, so the case must be discarded.

The simplest way to decrease the effects of work hardening is to decrease the pressure in the case. Loading to the minimum power level listed in the reloading manual, instead of the maximum, can significantly increase case life. Slower powders generally also have lower pressure peaks. If the manual lists pressures for each load given, then pick a powder and load that gives a low peak pressure.

Annealing brass to make it softer and less brittle is fairly easy, but annealing cartridge cases is a more complex matter. Since the base of the case must be hard, it cannot be annealed. What is needed is a form of heat treatment called differential hardening, where heat is carefully applied to part of the case until the desired hardness is reached, and then the heat treatment process is halted by rapidly cooling the case. Since annealing brass requires heating it to about 660 F (350 C), the heating must be done in such a way as to prevent the base of the case from heating up and losing its hardness. The traditional way is to stand the cases in a shallow pan full of water, then heat the necks of the cases with a torch, but this method makes it difficult to get an even heating of the entire case neck. A better method according to some is to mark the case (with the head standing in water) with a 660 F (350 C) temperature sensitive crayon at the point to which it is to be annealed (just behind the shoulder for bottlenecked cartridges, near the bullet seating depth for straight wall cartridges). Latch the cartridge base into a holder, such as a shell holder, that will securely hold it while you spin the case. Place the neck of the case in a propane torch flame, and heat it until the crayon mark changes color, indicating the correct temperature--the surface of the brass will also attain a bluish shade as it oxidizes slightly due to the heat. Once the correct temperature is reached, quickly quench the entire case in water to stop the annealing process and prevent the heat from reaching the base of the case. Attempting to do this entirely in air, without standing the case in water, will most likely anneal the case near the head, softening the case where it must be hard to function properly, as the heat flow will reach the head before the quenching can be done.

Cases that have small cracks at the neck may not be a complete loss. Many cartridges, both commercial and wildcats, can be made by shortening a longer cartridge. For example, a .223 Remington can be shortened to become a .222 Remington, which can further be shortened to become a .221 Fireball. .30-06 Springfield can become .308 Winchester, which can become .308 x 1.5 or any number of specialized benchrest shooting cartridges. Since the cracking is likely due to a brittle neck, the cases should be annealed before attempting to reform them, or the crack may propagate and ruin the new case as well.

[edit] Minimizing powder cost

Powder is another significant cost of reloading, and one over which the handloader has significant control. In addition to the obvious step of using a minimum charge, rather than a full power one, significant cost savings may be obtained through careful powder choice. Given the same bullet and cartridge, a faster burning powder will generally use a smaller charge of powder than required with a slower powder. For example, Accurate Arms lists 5 powders as suitable for a .44 Magnum firing a 240 grain lead semi-wadcutter. AA #2 is a very fast pistol powder, while AA #9 is a very slow pistol powder, and loads are listed for both of these. The minimum loads listed are 9.0 grains (0.6 g) of AA #2 for a velocity of 1126 ft/s (343 m/s), and 19.5 grains (1.3 g) of #9 for 1364 ft/s (416 m/s). The difference is 777 loads per pound (1710/kg) for AA #2, and 358 loads per pound (789/kg) for AA #9. All the Accurate Arms pistol powders cost the same per pound, about US$16, so the difference is US$0.0206 vs. US$0.0447, equating to over 2 cents per round. Where the tradeoff comes is in terms of power and accuracy; AA #2 is designed for small cases, and will burn inconsistently in the large .44 Magnum case. AA #9, however, will fill the case much better, and the slow burn rate of AA #9 is ideal for magnum handgun rounds, producing 20% higher velocities (at maximum levels) while still producing less pressure than the fast burning AA #2. A medium burning powder might actually be a better choice, as it would split the difference in powder weights while delivering more power and accuracy than the fastest powder.

One solution that is applicable to revolvers in particular is the possibility of using a reduced-volume case. Cartridges such as .357 Magnum and .44 Magnum are just longer versions of their parent rounds of .38 Special and .44 Special, and the shorter rounds will fire in the longer chambers with no problems. The reduced case capacity allows greater accuracy with even lighter loads. A .44 Special loaded with a minimum load of AA #2 uses only 4.2 grains (270 mg) of powder, and produces a modest 771 ft/s (235 m/s).

[edit] External links

  • Low Pressure & High Velocity with Cast Bullets, from Jesse's Hunting and Outdoors
  • Corbin, maker of commercial and consumer grade bullet swaging equipment, including the equipment to turn .22 LR cases into jacketed bullets
  • Comparison of various 9 x 19 mm expanding bullet loads, including the Speer Gold Dot plated bullet
  • Gun Tests article on case annealing.
  • Accurate Arms, source of loading information for fast vs. slow powder comparison
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