Sling (firearms)

In the context of firearms, a sling is a type of strap or harness designed to allow a shooter to conveniently carry a firearm (usually a long gun such as a rifle, carbine, shotgun, submachine gun or GPMG) on their body, and/or to aid in greater hit probability by allowing the firearm to be better braced and stabilized during aiming. Various types of slings offer their own advantages and disadvantages, and can generally be divided into several categories.

There are several mounting standards for attaching a sling to a rifle, of which some well known are sling swivel studs, QD/ Flush Cup or snap hooks (i.e. HK-type snap hook or Magpul Paraclip).

Sling mounts also come in different widths for different webbings. The webbing on American slings are typically 1, 11⁄4 or 11⁄2 inch (25.4, 31.75 or 38.1 mm) wide, while European slings typically are 20 or 30 mm (0.79 or 1.18 in) wide.^{[citation needed]}

A sling swivel stud, sometimes called an "Uncle Mike type swivel" after one of the manufacturers, is one type of sling mounting interface. Sling swivels can be mounted to a long gun in various ways, for instance with wood or machine screws attached to the stock, a barrel band, or by using adapters to other mounting standards such as Picatinny or M-LOK.

Sling swivel studs can vary in dimensions. The widest round part of the stud typically measures around 8.9 mm (0.350 inches), the spacing between the flats measure around 7.6 mm (0.3 inches) and the hole for mounting a sling adapter measures around 3.7 mm (0.145 inches).^{[citation needed]}

Quick detach sling mounts (QD), also called flush cup sling mounts, is another type of sling mounting interface. "QD sling swivel" usually refers to the part attached to the sling, while "flush cup" refer to the corresponding socket on the firearm.

The system consists of a push button swivel attached to the sling (approximate diameter 9.4 mm, a little under 3⁄8 inches) which is placed into a mounting socket on the firearm (approximate diameter 9.6 mm, a little over 3⁄8 inches). The swivel is kept in place by a four ball detents connected to the push button, which presses against the walls of the socket. The sling swivel can quickly be taken on and off by pushing the QD button, which retracts the ball detents. The flush cup sockets can be either rotating or non rotating.

Flush cups can be mounted to a long gun in various ways, for instance by drilling a hole in the stock and screwing in flush cup socket, or by using an adapter to other mounting standards such as Picatinny or M-LOK.