It's Not Indigestion, I'll Eat What I Like (Napoleon's Spanish Ulcer Book 3)

Commodore (Brigadier) Sir Joshua Welbeloved increases the Hornets to company strength and recruits enough of Napoleon's Hanoverians to make a German company. They harass the French from Ciudad Rodrigo and Almeida to the battle of Buçaco and the lines of Torres Vedras, then return to the mountains and cut off all French communications with Spain.
Further recruitment is made, to increase their strength to four companies - British - German - Portuguese and Spanish.
The Condesa's blacksmith modifies captured French muskets to breech-loaders with 200 yards accuracy. He also converts some Baker rifles to breech-loading.