I never had much luck with the thicker fiber wads. Like Mike said, I believe they were distorting the patterns when I tried them. Using them other ways, or cutting them down may have helped.
I did have luck with thin (1/16 I think)" wool wads lubed and stacked. They are light and in theory, would fall out of the shot and not turn into another projectile. The wool and finer wads can help the pattern by absorbing some energy as the load is fired which helps keep the integrity of the shot column.
In my jugged barrel, I shoot a nitro card above and below the shot. Seems odd because they are dense and hard and have some weight..but I've never recovered one..I tried a lot of loads trying to get the jug to shoot well. That worked best so far.
Each gun is different. Patterning is enjoyable to me. An excuse to shoot. Every little difference can make a dramatic difference in the pattern.