There is a lot of confusion regarding this system which is critical to proper operation. I’m going to try to clear it up by discussing the parts, how they work, what happens when they’re set up right — and set up wrong. Except for magnums, there are 3 parts: the Bronze Friction Piece, Friction Ring, and the Friction Spring. The picture below shows those parts along with Recoil, Magazine, Action Springs, and a Mag Spring Retainer. The Bronze Friction Piece (BFP) is just a brake. It’s split so that it can contract in compression around the Magazine Tube. The Friction Spring goes over it to hold it snug. For light loads, the Friction Ring isn’t used. The BFP sits at the top of the Recoil Spring with its bevel facing forward. This mates to a corresponding bevel in the Barrel Ring. When the gun is fired, the barrel recoils aft and the front of the BFP is squeezed causing friction, slowing the barrel’s (and the bolt it’s locked to) speed down to an acceptable level. For heavy loads, the steel Friction Ring is placed between the Recoil Spring and the BFP with its bevel forward. Now when the gun fires the BFP gets squeezed from the front and the back — doubling the braking. The question always asked is “What is a heavy load?” To me, a heavy 12 gauge load is anything greater than 1 1/8oz @ 1200fps. But it really depends on your gun. If you’ve replaced your Recoil and Action Springs recently you’ll find you need the light setting for all but the most powerful shells. Or if your BFP is worn and your springs weak, the heavy setting will work with light target loads. For that reason, always start out with the gun set up for heavy loads. If it won’t cycle, add a few drops of motor oil before changing to the light setting. For really heavy loads, wipe the mag tube dry before firing.