Ancient pressure-distance curves

[Linked Image from photos.smugmug.com]

[Linked Image from photos.smugmug.com]

Modern, but computer generated

[Linked Image from photos.smugmug.com]

Clearly modern fast powder have a higher 1" pressure which then falls more rapidly than old Bulk or "progressive burning" powders, even with the same total area under the curve

Last edited by Drew Hause; 11/01/22 11:53 AM. Reason: Images restored