Faced with financial difficulties due to cotton gin patent infringements, Whitney secured a contract from the U.S. government to produce 10,000 muskets. This provided him with a much-needed source of income and an opportunity to apply his mechanical skills to a new field.

Whitney established an armory in Hamden, Connecticut, to fulfill the government contract. He invested in machinery and developed innovative manufacturing processes to produce muskets efficiently.

Although the extent of Whitney's actual implementation of interchangeable parts is debated, he is widely credited with popularizing the concept. He envisioned producing muskets with standardized, interchangeable parts that could be easily replaced, simplifying repairs and maintenance.

Whitney faced significant challenges in fulfilling the musket contract on time. Technical difficulties, labor shortages, and financial constraints contributed to delays, drawing criticism from government officials.