My favourite gun is a Beretta 686 Silver Pigeon S 20 gauge. It is a beautiful gun, but one I have not had a sling on because I was not that keen on drilling into the barrel to attach the swivel fittings.
Wanting to use the 686 I looked on the net for a solution that did not involve drilling into the barrel. Uncle Mike’s have a wonderful product that has allowed me to fit swivels on the gun without having to drill into the barrel.
This means I am able to use my favourite gun without getting sore elbows, which happens every season from carrying a gun around every day. It gets far worse without a sling.
Reloaders carry the 12 gauge version of this swivel attachement.