both of these French claims, the most likely inventor of the percussion cap, according to historian Sidney James Gooding, was Joseph Egg (nephew of Durs Egg), around 1817, .

There were other earlier claims. Col. Peter Hawker in 1830 simultaneously claimed and denied being the inventor. "I do not wish to say I was the inventor of it - very probably not" but then immediately recounts that he came up with the idea of simplifying