Pivot pin with installation aperture

A pin, comprising:

• a head;
• and
• a shaft that extends from the head, the shaft defining a detent-retention channel that extends along the shaft, the shaft defining an installation aperture opposite the channel from the head, the channel being configured to receive a detent and to enable the pin to slide relative to the detent in the channel between a locked configuration and an unlocked configuration, the installation aperture extending entirely through the shaft,
• wherein the installation aperture has an inner diameter that is smaller than an outer diameter of the detent and at least as large as an outer diameter of a tool,
• whereby the installation aperture in the shaft facilitates simplifying installation of the pin.

A pivot pin for a coupling an upper receiver of a firearm to a lower receiver of the firearm, the pivot pin comprising:

• a head;
• and
• a shaft that extends from the head, the shaft defining a detent-retention channel that extends along the shaft, the shaft defining an installation aperture opposite the channel from the head, the channel being configured to receive a detent and to enable the pivot pin to slide relative to the detent in the channel between a locked configuration and an unlocked configuration, the installation aperture being configured to receive a tool that extends through the shaft and to enable the detent to be urged by the tool into a detent recess in the lower receiver while the shaft covers the detent recess in the lower receiver and while the tool extends through the shaft,
• wherein the installation aperture has an inner diameter that is smaller than an outer diameter of the detent,
• whereby the installation aperture in the shaft facilitates reducing a likelihood that the detent escapes from the detent recess in the lower receiver during installation of the pivot pin in the lower receiver.