It's generally accepted that tactical slings should be mounted on the side of the weapon. GG&G manufactures Front And Rear "Sling Thing" Sling Attachments that provide standard 1 1/4 inch sling swivels in this preferred sling mounting position.

Features:
A lightweight and versatile way of attaching a sling to an AR-15/M16 front sight
Ambidextrous
Robust and rigid
6061-T6 solid aluminum alloy