A self-locking pin having a shaft, a headed end, and plunger biased in a bore in the pin. The portion of the detent or plunger that extends outwardly from the bore may be wedge-shaped, or possess other geometrical shapes, while the portion of the plunger disposed inside the bore is of a cylindrical shape or other geometrical shapes. The plunger comprises a plunger section and a biasing section in a unitary one-piece construction. At least one transition ledge is defined on the plunger. The shaft is staked at points along the perimeter of the bore so that the inwardly extending surface created by the staking abuts the transition ledge and prevents the plunger from rotating or being removed from the bore.