David Wareham offers a set of free wargames rules for the 19th Century along with army lists. Scale is 1 figure to 30 men.
19th Century
Gold Rush Mounties Rules
Gold Rush is a set of free wargames rules for late 19th century action in the Yukon.
Law of the Gun Wild West Rules
Law of the Gun is a set of free wargames rules by Richard Bradley for Wild West Skirmishes.
Fire and Furia Francese
Fire and Fury Francese, from Nick Dorrell, is a variant of my all time favorite wargaming rules set, Fire and Fury. Whereas Fire and Fury is designed for the American Civil War, F&F-F is for playing miniatures games set in the European wars of the mid 19th century, such as the Crimean War and the Franco Prussian
The Four Eyed Dog Is Dead Taiping Rebellion Rules
The Four Eyed Dog is Dead is a set of free wargames rules for games set in the Taiping Rebellion.
For what it’s worth, the Taiping Rebellion is one of the least known — and at the same time, deadliest — conflict in world history. Taking place in China from 1950 to 1864, best estimates say that the Taiping Rebellion resulted in between twenty and forty million dead.