Single point slings suck for most every application except shooting on a range standing up.
You can convert a useful two point sling to a crappy single point sling with the click of a button with an adaptor.
A single point sling requires you to use a hand to control the weapon in most movement and especially if you are getting into a crouching or prone position. Otherwise your barrel will stick in the dirt. Just walking--forget runnning--with a single point sling is a chore. Stupid gun bounces around.
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