handloading

thumb|Components of a modern bottleneck rifle [[cartridge. Top-to-bottom: Copper-jacketed bullet, smokeless powder granules, rimless brass case, Boxer primer.]] thumb|Hole|Slotted [[trays or "loading blocks" that hold empty cases awaiting handloading and completed cartridges (top right area)]] Handloading is the practice of making firearm cartridges by manually assembling the individual components (metallic/polymer case, primer, propellant and projectile), rather than purchasing mass-produced, factory-loaded commercial ammunition. Handloading using previously fired cartridge cases or shotshells is called reloading (should not be confused with the reloading of a firearm with cartridges, such as by swapping detachable magazines, or using a stripper clip or speedloader to quickly insert new cartridges into a magazine). While the root "loading" refers to the filling of muzzle loading firearms with propellant (originally with black gunpowder or less commonly smokeless powder) and a bullet, most of the actual handloading process involves the cartridge case and its preparation. Unlike the propellant, primer and projectile (bullets, shot and slugs), which are all single-use consumables, the case is the only reusable component and its shape, internal capacity and crimping tension are crucial factors influencing the internal ballistics of the cartridge.

The term handloading is the more technical term that refers generically to any manual assembly of ammunition cartridges, although reloading is often used interchangeably since handloading more often than not involves used cases and the loading techniques are largely the same regardless whether the cases are brand new or having been previously fired (used). The only differences lie in the initial preparations — new cases are generally ready for loading straight out of the box, while previously fired cases often need additional procedures to prepare them for loading. This can include basic operations such as removal of expended primers ("depriming"), case cleaning (with water, ultrasound or abrasive media to remove fouling and/or corrosion residue) and/or burnishing/polishing, deburring and resizing to return the case to it's pre-fired shape or to reform from fire forming or to experiment with custom modifications (wildcatting), trimming the cases to length, or more advanced operations such as reshaping (to correct any pre-existing deformations, or for caliber conversion).