When selecting a firearm ensure that you meet the minimum age requirements for purchasing the firearm and the ammunition associated with the firearm. The ATF in § 922(b), “unlawful acts”, states it is unlawful for any licensed importer, licensed manufacturer, licensed dealer, or licensed collector to sell or deliver:

1. Any firearm or ammunition to any individual who the licensee knows or has reasonable cause to believe is “less than 18 years of age”, and, if the firearm is other than a shotgun or rifle, or ammunition for a shotgun or rifle, to any individual who the licensee knows or has reasonable cause to believe is less than 21 years of age. (In laymen’s terms anyone purchasing a shotgun or rifle or ammo for a shotgun or rifle must at a minimum be eighteen years of age. To purchase a pistol or ammo for a pistol the individual must be at a minimum twenty-one years old).

Once you have met the age and other legal requirements of the state you reside in (see gun laws by states), decide for what the purpose the firearm is being purchased. Some categories may be: