Who was the man that killed no fewer than 42 people as a gunfighter and was the son of a methodist preacher?

John Wesley Hardin

Explanation:

This individual is a figure in the American Old West, and is known as a folk icon as well - through a rather controversial one, since he is a criminal. John was born in Texas on 1853 and died there as well on 1895, when he was 42 years old. He was murdered by another outlaw, John Selman, one year after he was released from prison; where he has served 17 years out of his 25 years' prison sentence.