Hello zxcvbob,,,
Thanks for more insight on the topic.
I had just read an article on leading in a 10 year old magazine,,,
They did mention most of the factors you talked about.
What I found interesting was that at low velocities (under 900 fps) they could not induce leading,,,
At higher velocities they got leading very easily.
What was most interesting were the pictures of the high velocity rounds,,,
All of the recovered lead bullets has obvious melting at the base.
This was where they drew their conclusion of "lead steam" being the major culprit in leading.
I should have "liberated" the magazine,,,
it was an old Guns and Ammo at my doctors office.
Aarond