For those of you who are unaware of it, this is an absolutely invaluable resource for accessing historical documentation. The U.S. Army Center of Military history:

LINK

The center, has an enormous amount of documentation available on-line and this (thanks to Dan Fong at Missing Lynx) is one of their latest on-line documents which many should find invaluable:

THE ORDNANCE DEPARTMENT:
ON BEACHHEAD AND BATTLEFRONT (Link)