Originally Posted by limj147
So am I thinking bout reloading, but I wanted to know what determines a small/large rifle/pistol? If there is a thread on this the link would be great.
Welcome to the forum. The best thing you can do to learn about reloading is to sit down with a reloading manual and read about the basics of loading. Here is a wikipedia article on ballistics; http://en.wikipedia.org/wiki/Internal_ballistics
If you are speaking of primers, then there are boxer (American) and Berden (European) primers, large and small primers, both in pistol and rifle versions. While the Berden primer was invented in the USA, it is rare here because the two flash holes in the primer pocket inhibit easy de-capping. The boxer primer is a European invention but popular in the USA due to its single flash holes that makes it easy to de-prime.
A large primer is .210" wide, small primers are.175" inches wide. Rifle primers have a harder cup than pistol primers. This means they need more force from the firing pin to activate the primer compound, but hold up to the much higher pressures. Magnum primers typically have a hotter flame to better (more consistently) ignite the large charge of powder in the large rifle cartridges.
209 primers are used in shot shells for shotguns. 50 bmg primers are even larger than large rifle primers and used in the 50 bmg cartridge which holds more than 200 grains of powder.
Metallic cartridges come in hundreds of shapes and sizes for just about any application a shooter needs. Here is another good link; http://en.wikipedia.org/wiki/Handloading
While these links might generate more questions than answers, they are a good place to start.
While most people reload ammo to save money, they frequently end up spending much more. Let's say an average shooter might spend $12 for twenty 223 Remington cartridges and spend $120 a year shooting that rifle. A person who reloads might only spend 25 cents per round to reload the same brass. A person with access to ammo this cheap might decide to spend at least $200 to reload/shoot the 800 rounds of ammo he can load at that price. In addition, the reloader can load ammo that is just not available at any price (wildcats) or custom load it to work the best in his or her rifle.