Coupling pins for connecting weapon components are described. An example fastener to couple weapon components includes an elongated body defining a first aperture. The first aperture being defined along a longitudinal axis of the elongated body. Tension member and a biasing element being positioned within the first aperture. The elongated body defining a second aperture. The second aperture being defined through a portion of the elongated body to enable a tension element, positioned at least partially within the second aperture, to be urged from the elongated by via an interaction with the tension member. The fastener is insertable into aligned apertures of respective first and second weapon components. The tension element being urged from the elongated body to interact with the second weapon component to urge the second weapon component into further engagement with the first weapon component.