The barrel has to be lubed to get good patterns. And the powder charges should be modest. Stay under 1100 fps at the muzzle. I recommend using FFg vs. FFFg in your shotgun. Dave's use of a 1/4 cushion wad soaked and drained in olive oil sounds like a good sensible approach for hunting. I have been using 1/2 cushion wads soaked in Moose milk( Water soluable oil, lestoil, and water- shake to mix before using) but I frankly don't see much improvement with the liquid detergent in the mix. And straight oil- even cheap cooking oil would do just fine on these wads. Keep them in a plastic sandwich baggie to keep them from drying out.
I have also been lubing my barrel with wonderlube on a cleaning patch after seating the OS card. That also works.
Lube not only helps the shot go down the barrel without rubbing lead off on it, to ruin subsequent patterns, but it insures that fouling does not stick in the barrel, also causing subsequent shots to not pattern well. Lead rubbing against steel is going to leave flat spots on the pellets. These pellets will fly out of the pattern very quickly after leaving the bore. To the extent that you can protect the lead from rubbing off on the barrel, your patterns have to improve. You do that by lubing the bore, ( when you run that lubed cushion wad down the barrel) and by reducing the velocity of the load. Reducing velocity also reduces pressure, and its the higher pressure that forces lead shot against the sides of the bore, and rubs the flats on them. FFFg powder burns too fast, giving you higher pressure, even with a reduced charge, so that you still get more flats rubbed on the outside pellets than if you were to use FFg powder. Then there is also the problem of the " Kick in the Ass " syndrome, whereby when using fast burning powders, the initial slam of gases into the wads causes the back, or bottom, 2-3 rows of shot to be flattened by the weight of the forward or upper pellets of shot. Flat pellets do not fly through air as well as round pellets, and round pellets have a terrrible Ballistic Coefficient to begin with. So, give your shot a softer push, rather than a " kick in the ass " to get it moving down the barrel. Your patterns will be better.
The use of cushion wads was done to help keep those bottom rows of shot from being deformed by the firing, and the concept is necessary even more today using smokeless powders at higher pressures. That is why you see cushions of all kinds of different designs on the bottom side of the plastic shotcups. Those pellets are going to be deformed substantially, unless buffered, with the higher velocities used in modern shotgun shells.
