Yeah, no dull moments for me mate.

I had a close look at the RCBS 40-400 PP bullets and there is a slight reduction in diameter about half way up from the base. It's only .002" or so and I don't think that it's accidental.
My patches are 1" long and the fold over is .200", so they are covering .800" of the bullet and at the top of the patch, the bullet measures .399. Perfect for a 40 cal bore. No wonder that it shoots so well in my rifle.

When tried in the muzzle, it is just a clearance fit.

I found a suitable piece of rubber for rolling them on.

Here are a couple of pix of my home made PP mould. Made from a piece of .224 barrel.

The ejection pin also forms the meplat on the bullet nose.