The primary purpose of a shooting sling is to provide additional stability by making the interface between the shooter and the rifle more rigid. A shooting sling is not ideally adapted to close-quarter engagements or tactical carry—its principal intent is to assist with marksmanship at distance. When it comes to shooting slings, the old military leather sling is the referenced standard, but the speed sling is faster.
Speed-sling techniques are not to be confused with what is often called the “hasty sling,” where you simply snake a traditional carry strap around your support arm. The hasty sling does nothing other than secure the strap so it doesn’t sway below the rifle while you try to hold on target. A speed sling, though it works in a similar fashion, it is also not the same as the military loop or competition sling. While a practiced rifleman can loop up a military sling in about 5 seconds, using a speed sling, the process can be completed in about 1 second. Speed slings are simply better suited to field use.
According to Gunsite Academy founder and author Col. Jeff Cooper, “The origin of the speed sling as rediscovered comes from Guatemala.” It was there where Cooper met Carlos Widmann, who had a rifle with a sling attached at the common forward position and just forward of the magazine. This attachment method allowed the shooter to quickly loop the sling behind the triceps of his support arm almost instantaneously while shouldering the rifle. Cooper named this configuration the CW Sling after Widmann. As Cooper soon learned, this system was not new—it was originally known as the British two-point system.
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