Quote:I have been having where my cast 32-40 bullets are not breech seating without using a rubber hammer to tap them in with the breech seater .
Brudford, I surmise your issue is your trying to breech seat the bullet
with a plugged case - not a for real by definition breech seater such as Russ Weber's. I too tried to seat 32-40 bullets (1:20) with a plugged case in my CPA. There was better than an inch of the case hanging out that would not go into the chamber by thumb seating.
So, it's going to cost you $200 for a real breech seater
As for the alloy,with a seater, not a plugged case, 1:20 alloy bullets will be easily seated. In the days of yore - Doc Hudson used 1:15 alloy for breech seating his 38-55 bullets.
But why your bullets are dropping at 0.324, IMO it is not an alloy issue if the mold is held tight when casting. Try this with a hot mold: put it in a padded vice and give it a hard squeeze. If there are no burrs on the pins, then a good probability the pins are not seated deep enough.
Be sure to lube the pins after the mold is up to temperature (I use paraffin wax) - Then cast some 1:20 and see what the diameters are
Good Luck