I've used these kinda slings at work(never needed a sling in airsoft) on a C7A2
http://www.oneshottactical.com/merch...ry_Code=SL-BFG
I used too loop the issue sling like this, worked well.
Also did the paracord an issue sling(see Black Hawk Down) thing untill my Vickers got to me.
http://www.oneshottactical.com/merch...ry_Code=SL-BFG
been using the Vickers Combat Application Sling since Sept an its working out well for me so far.