Hi,
The Sengoku Japan reference sheet and extension for Argad (a mix of RPG and skirmish rules) has been updated (translated from the most recent update in French).
It now includes an optional table for arquebuses firing in salvoes, and more explanations, suggestions, and ideas (10 pages).
http://www.argad-bzh.fr/argad/pdfs/sheet-en-japan-sengoku.pdf