The primary reason behind Mangal Pandey's behavior was because of a new type of bullet cartridge used in the Enfield P-53 rifle. It was rumoured that the cartridge was greased with animal fat (pig and cow fat), which neither Hindus nor Muslims consumed. The cartridges had to be bitten off to remove the cover, which was detested by both the Hindu and Muslim soldiers in the army. The general feeling was that British intentionally did it. What added to the discontent was that the Commandant of the 34th BNI (Bengal Native Infantry) was a known Christian preacher.
A stamp issued by the Government of India on October 5, 1984 commemorating the 'freedom fighter' Mangal Pandey.
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Many many thanks to “Apoorva Chandar” for providing ACK scan.