For leather slings I prefer a 1" sling and for a cotton web I prefer a 1.25 to 1.5 inch sling. I pretty much settled on Montana Rifle Slings years ago, they adjust quickly and work for a hasty sling. A good option is the old Garrand/military 1.5 inch cotton web sling that is battle proven and comes in green and black and cost less then 20 bucks. I encourage you to get on You Tube and look them both up.
I'm ordering a couple of the Garrand/military slings soon. They don't rot like leather and are cheap to make, which is why the military went to them. But, that does not mean they are not a good sling.
A good sling should carry what ever rifle it is attached to well and allow the user to quickly use it as a shooting aid if needed.
