Single axis lock and pivot for a selectively configurable firearm sight

A selectively configurable sight for a firearm comprising:

• a base including a mounting portion mountable on a firearm rail, the mounting portion including a flange defining a plunger hole;
• a sight element pivotally mounted to mounting portion, the sight element including a first side surface and an opposing second side surface, a front surface and a rear surface with a sight window defined by the sight element, extending from the front surface to the rear surface, the sight element selectively configurable in an upright position and a down position;
• a bias element configured to engage the sight element and urge the sight element to the upright position;
• a bore extending between the first side surface and the second side surface of the sight element, the bore including a longitudinal axis and a first surface;
• and
• a plunger reciprocally slidable in the bore along the longitudinal axis, the plunger including a first end manually engagable by a user, and a second distal end, the second distal end including a head registered in the plunger hole such that the plunger head is non-rotatable relative to the flange, the head including a first head locking surface and a second head locking surface offset from the first head locking surface,
• wherein the plunger is configurable in an upright locking mode in which the first head locking surface engages the first surface to maintain the sight element in the upright position, while the head at least partially protrudes into the plunger hole,
• wherein the plunger is configurable in a down locking mode in which the second head locking surface engages the first surface to maintain the sight element in the down position, while the head at least partially protrudes into the plunger hole,
• wherein the plunger is configurable in a free mode in which the head is disengaged from the first surface so that the sight element can be rotated about the longitudinal axis from the upright position to the down position.

A method of selectively configuring a sight comprising:

• providing a base including a mounting portion defining a plunger hole;
• sliding a plunger along a longitudinal axis in a first direction in a plunger bore defined by a sight element in a down position, the plunger including a first end and a second distal end, the second distal end including a head, the head sliding in the plunger bore, so as to configure the plunger in a free mode in which the head disengages the plunger bore so that the sight element is free to rotate about the longitudinal axis from the down position to an upright position;
• biasing the sight element from the down position toward the upright position with a bias element;
• and
• releasing the plunger when the sight element attains the upright position so that the plunger slides along the longitudinal axis in a second direction, so the head engages the plunger bore so as to configure the plunger in a locked upright mode so the sight element is locked in the upright position.