Cowboys and Zombies (2010)

California gold rush, late 1800's: A gun slinging bounty hunter (Mortimer) travels deep into the mountains to find a deadly Apache warrior (Brother Wolf) who is wanted by the law. Along the way he passes through a gold mining Town. The miners help direct Mortimer to the Apache and send him on his way.
Mortimer enters the forest and begins to track the Apache. Back in town, the miners un-earth an ancient meteor. They use their pick axes to crack it open. A section of the meteor splits apart and spores explode out of it. The spore surround and infect the entire population of the mining camp. They are transformed into ravenous mutants.
After a vicious battle against the Apache warrior, Mortimer exits the forest with his prisoner in shackles. They hike back to the mining town to find them selves surrounded by a horde of blood thirsty mutants. Now Mortimer the gun slinger and Brother Wolf the Warrior must join together to survive the mutant hordes. What ensues is a bloodbath of horror for the Dead and the Damned.