Mini-14 rifle was developed in early 1970s and introduced near 1974. To speak simply, Mini-14 is M-14 "clone", scaled down to use then-new 5.56mm / .223 Rem cartridge.

Mini-14 is somewhat similar in design to M1 Garand and M-14 rifles, utilizing same gas action with underbarrel gas piston, rotating bolt, positive safety with safety switch located at the forward part of the triggerguard. Mini-14s initially were manufactured in both semi-auto only "civilian" versions and in select-fire "military" versions, featuring flash hider and bayonet mounts. However, these "military" rifles weren't adopted by any military, and were used to some extent by some Police departments and Law Enforcement agencies across the USA. Those select-fire versions, known as AC-556 or Mini-14GB, were manufactured with one piece wooden stock or with pistol grip and side-folding metal buttstock.

In 1987, Ruger developed Mini-30 version of the semi-auto Mini-14, chambered in 7.62x39mm Russian cartridge.

All Mini-14s and Mini-30s are known as reliable rifles, but accuracy is inferior, compared to M16/AR-15 series.