Put your sling swivel on your gun.
Wear the thickest shirt/jacket you will use when slinging the SG.
Take a double length of paracord and run it between the swivels.
Adjust length until it feels comfortable. Knot to hold length.
Take swivels off of SG and stretch paracord/swivel combination out on a table.
Measure distance between swivels.
Add 1 ft for every inch of measured length.
Example:
I adjust sling so I get 36 inches of para-cord between swivels.
36 x 2 = 72 inches.
36 inches x 1 ft = 36 ft.
Total length required = 36 ft + 72 inches + wiggle room.
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