No one wants to share their recipe for success? I make my own with wads cut from common heavy card stock. The stock on the back of a desk calendar works fine. Since pack rats had shredded the wiring harness in my Gladiator I had a score to settle. So,,, a wad punch was in order.
You may not need as many as I so a sacrificial case chamfered on the outside will work. Just put the card stock on an old magazine and give the case head a whack with a mallet. You'll need a length of wire to push through the primer flash hole to knock the wad out.
It goes without saying to size and prime, but to help retain the overshot wad I give them a light, very light, crimp.
Since I have a 357 that's the brass I use. The shot charge I wanted was 158gr or as close under as I could get so I chose a low-moderate velocity charge of Universal which a .5cc Lee dipper gives.
Drop your powder charge and tip the over powder wad into the case and press it down onto the powder.
What I ran into was a 158gr shot charge overfilled the case so I picked out enough to leave room for the overshot wad and then weighed it. It came out to just over 150gr. I then found the Lee dipper that held just that much shot even at the top of the dipper. Add the shot charge and press an overshot wad into place. It should be just inside the light crimp. I then add a thin bead of super glue around the edge of the wad to help hold it against recoil.
If you find you have excess case space add wads over the powder to bring the shot up.
In this case you need to weigh shot and wads together. Your payload weight Cannot exceed max bullet weight for the powder charge used.
So long as you stay at or under max payload weight,
shot and wad weight combined, for your powder charge your pressure will be safe.