personally I don't use a filler such as corn meal etc.
In my colts and remingtons I adjust the powder load.
In mine as you look into the chamber you can see a distinct ridge where the chamber is reamed larger where the powder resides as compared to where the ball sits.
Where the ball sits when compressed is smaller so that the ball will be compressed to provide the seal needed.
I almost exclusively use paper cartridges as it is faster in the field.
Most times I don't use a wad.
However, with experimentation I roll and fill the cartridge. Insert in the chamber. If leaving loaded for extended period I either use a dry wad, or a larger powder load, to bring it high enough up in the chamber, so a ball seated witll be in compressed area.
Now some don't know this.
As you seat the ball, it grows in length as it is compressed in diameter.
Thus you can actually seat the ball deeper than you would believe.
If I am shooting right away (same day) I use a lighter load and a wad, or a medium load and no wad. Whatever gives me best accuracy for targets and hunting.
If loading and it will be sitting for a extended time, like for home defense,then I use a near maximum load paper cartridge, no wad very dry cylinder and the ball.
I rarely use balls anymore. I use conicals with grease grooves. I pan dip the bullet to fill the grooves.
I save the cornmeal for muffins and cream of wheat for breakfast.
My apologies for long winded.
This was not meant to be directed at any one person, just a general to the topic at hand.