buckstix-
Two editions of Jack Lott's Big Bore Rifles were published by Peterson Publishing Co. Both were of the usual magazine format.
The first edition from 1983 was labeled "Guns & Ammo Action Series #1" on the cover. ISBN 0-8227-2335-2, 96 pp. All fourteen chapters appear to have been written by Lott. The editors were Boddington and Libourel.
The second edition was published in 1994 after Jack Lott's death. ISBN 0-8227-3185-1, 98 pp. Four of the chapters in this edition are reprints of Lott's chapters in the first edition, with uneven editing. Other chapters are written by Aagaard, Taylor, Boddington, Rees, Kronfeld, Sitton, Siatos, Wooters, Coogan, and Barsness.
Specific to your question on the 475 A&M: The only mention I found was a single paragraph in the chapter "Ultra Magnum Wildcats". Here's the wording from the first edition:
"One would assume that there would be no demand for wildcats of over .458 caliber, but there is and has been for decades, including the monster .475 A&M (Atkinson & Marquart) based on the .378 Weatherby Magnum case. It uses the .475-inch bullet for the .470 Nitro-Express in 400, 500 and 600-grain weights and boasts a velocity of 2,980 fps with a 500-grain bullet and 110 grains of 3031, and a 600-grain bullet at 2,502 fps with 105 grains of 3031. Such a velocity as 2,980 fps for a 500-grain .475 caliber bullet is, of course, absurdly excessive, and regardless of construction, any expanding 500-grain bullet at such a velocity will explode on impact.
(The editors of the second edition altered this paragraph to the point of nonsense.)
--Bob
