Thursday, July 12, 2012

Reloading Ammunition: Basics

Many moons ago, when we first discussed centerfire cartridges, brief mention was made of the fact that these cartridges can be refilled by users after use. We will study more on that topic in this post.

Centerfire cartridges are detonated by having the striker of the firearm strike a primer cap at the base of the cartridge, which causes the shock sensitive primer to ignite, thereby igniting the propellant in the cartridge. Unlike a rimfire cartridge, where the rim gets deformed by the striker, a centerfire cartridge case generally remains intact even after shooting the cartridge. This means that it may be possible for the cartridge case to be refilled and reused after it is fired.

There are several reasons why people reload cartridges:

  1. A person may be using a firearm that uses an uncommon caliber cartridge or the firearm may be so old that the ammunition has gone out of production.
  2. A person could have purchased the firearm in one country where the ammunition for it is common, but not so easily obtained when the person moves to another country. For instance, 6.5x54 mm. Mannlicher-Schoenhauer cartridge is popular with big game hunters in Europe and Africa, but is not so easily available in the US. Conversely, the .40 caliber S&W cartridge is easily available in the US, but not so easily found in Europe. And while .45 ACP ammunition is popular on both sides of the pond, the Europeans pay more for it than we do.
  3. The price of ammunition might have increased due to external circumstances and it is no longer affordable to keep purchasing new ammunition. For instance, the price of ammunition in the US has been rising in recent years, due to various reasons such as the war on terror, election jitters, increased Chinese demand for metals like lead and copper drove up the prices etc.
  4. Cutting costs, especially in a down economy. A person may save 25% - 50% of the cost of purchasing from a factory. For rarer ammunition, the cost savings may be even higher.
  5. Some may want more accuracy or performance out of their firearm which they can't obtain with factory loaded ammunition. 
  6. There may not be any factory producing ammunition for a specific combination of bullet and cartridge, so users might have to produce their own. This is especially true for people who like to experiment with wildcat cartridges.
  7. Purely as a hobby. There are examples of rich people who could easily afford to buy new cartridges, but prefer to reload their own cartridges by hand, simply because they like it.
Image licensed under GNU Free Documentation License 1.2 by user Arthurrh at Wikipedia
Click on image to enlarge

In the above picture, we see a disassembled rifle cartridge. From top to bottom, the various components are: the bullet, the propellant granules, a brass cartridge case and a tiny primer cap at the bottom. In our discussion about centerfire cartridges from many months ago, we noted that it was easier to reload cartridges designed for Boxer-type primer cap vs. Berdan-type primer cap. In the US, most cartridges use boxer-type primer caps, thereby making the reloading job much easier.

The most expensive part of the cartridge is the cartridge case and fortunately this may be reused many times and the cost of this is in the user's control. The second most expensive part of the cartridge is the bullet and unfortunately this cannot be reused after firing, as it generally splits into many fragments or gets deformed badly upon hitting something. Hence, bullets need to be either purchased from a manufacturer, or cast or swaged by hand by the user. If purchased from manufacturer, these cost about $50 for a bag of 500 9 mm. bullets. Other bullets may cost more or less than this, depending on bullet size, materials used, type of bullet etc. For bullets that are obsolete, people have to cast or swage their own. The third most expensive part is the propellant, which typically costs about $15 - $30 per lb (1 lb = 0.45 kg) depending on powder quality and this is also something that the user can control costs with. Also, depending on the type and size of ammunition being reloaded (shotgun shell vs. pistol cartridge vs. rifle cartridge etc.), the user may be able to reload anywhere between 175-1500 cartridges with 1 lb. of propellant, which can go a long way into controlling costs. Depending on the type of cartridges being refilled, the user may be able to refill so many cartridges that the cost of propellant per cartridge may actually be lower than the cost of the primer cap. The least expensive part of the cartridge is usually the primer cap and these are generally purchased from a manufacturer in bulk. They are not that expensive anyway -- typically, a bag of 1000 primer caps costs about $30.00 - $40.00 or so, which works out to about 3 - 4 cents per cartridge.

With that said, there are also setup costs of purchasing reloading equipment e.g. press, dies, case trimmer, weighing scale, priming tool, bullet puller, case lubricants etc. However, most of these only need to be purchased once and can be used for several years without replacement.

We will look more into the topic of reloading in the next few posts.

No comments:

Post a Comment