If I have a free float tube on my rifle I dont attatch my sling to barrel in aynway.

All of my slings on my AR's are attatched to the front of the FF tube. I do this for a reason though. It works for me because I am left handed and I have to keep the sling out of the action of the gun to avoid jamming. So that is why I run my sling the way I do.

however I have ran many many rounds through it with the sling attatched to the rear of the FF tube and to the Front and have never had a jam either way. I just notice that the sling gets close to the action in some postions and it just makes me uncomfortable,when I have it attatched to the rear, so I keep it upfront.

My .02