Gibby,
I think you can accomplish the same thing with a $20 Lee (Pistol) Factory Crimp Die. I bought one for 10mm and a Lee Bulge Buster, ran all my .40 & 10mm brass through it, sized them all the way past the rim. Would have ironed out the Glock smiles, but I don't have a firearm to cause them.
Me neither.
I do not own a glock.
The redding's bottom ring is larger than the top ring. Conserves the taper in the case somewhat. Two step.
But like I have said many times, I like the bulge at the bottom of the bullet.
I use Lee's factory crimp dies on many calibers.
For the 10mm, I bought the Redding pass through. But my loads are not that hot. I do not use it much.