First gun made by an assembly line?

Answer 1

Eli Whitney was known as the inventor of the cottoin gin (machine to remove the seeds from newly picked cotton). However, he was also one of the first to establish mass production of anything- the muskets made by his company used standardized parts- so hammer from one musket would fit another, a barrel from one would fit any other, etc. Henry Ford, founder of the Ford Motor Company is generally accredited with the assembly line- where each worker added the same part to each vehicle that moved past him on the line. But without the standard parts pioneered by Whitney, Ford could not have created the assembly line- each part would have required hand fitting.