.17 Rimfire

.17 Rimfire may refer to a number of different cartridges or firearms that use them. The cartridges all use rimfire cases and fire .17 inch (4.5 mm) bullets. While .17 caliber airguns generally use .177 inch projectiles (4.50 mm), .17 caliber firearms, both rimfire and centerfire, generally measure .172 inch (4.37 mm).

.17 Rimfire cartridges include:
 * .17 HMR, or .17 HMR, the first major production .17 caliber rimfire, introduced in 2002
 * .17 HM2, or .17 MH2, introduced in 2004.
 * The .17 PMC/Aguila introduced as .17 High Standard and .17 Aguila in 2003/2004.
 * .17 Winchester Super Magnum introduced in 2013
 * Any of a number of .17 caliber wildcat cartridges based on rimfire cases. Most of these were, like the .17 HMR, based on the .22 WMR.