You have six replies below all telling you the same thing,so you can believe it for sure!
Wads DO help as stated.You'll find almost all serious chunkgun shooters using Wonder Wads over the powder then a PRB. I use them for this as well as hunting,and it pays off.
I've got a couple of new .40cals that I am presently working up loads for,and I can't get .40cal Wonder Wads. I bought a bag of 500 Circle Fly 410 shotgun fiber cushion wads to experiment with,and these work great in a .40cal because they are actually .410cal which is what a 410 shotgun is :winking:. I heat a 25% beeswax/75% bear oil combination and soak the cushion wads in this while it's in liquid form until the wads stop bubbling then remove and let cool down. The 25%/75% mix solidifies at room temperature so you aren't left with a bunch of greasy fiber wads.These things work great.Lubes the bore just right for a PRB,and doesn't affect the powder as far as I can tell.Accuracy definately IS improved,and I swear you could use most of the patches over again!