knowyourphrase.com - The Meanings and Origins For Several Common Idioms and Phrases
A person. Sometimes used to describe someone who is behaving badly.
The idea for this phrase is that a bullet was, at one point, inadvertently shot through the scrotum of a man and was thus carrying some sperm on it. The bullet then lodged itself into the abdomen of a woman, impregnating her. The chances of this sort of scenario actually happening, however, looks to be highly unlikely, if not impossible.
The above scenario was replicated as closely as possible―obviously not with real humans―on a television show called Mythbusters. They concluded that the myth was 'busted,' and said: "There's just no way that any biological material would survive on that hot bullet."
Morever, the website Snopes responded to the claim that during the Civil War, a sperm carrying bullet penetrated the ovaries of a woman and impregnated her, saying that: "The miraculous 'bullet pregnancy' orginated with an article that was printed as a joke in the journal The American Medical Weekly on 7 November 1874." The article mentioned was written by Legrand D. Capers. After it was written, in a subsequent issue there was an editor's note that implied the article was to be taken more as a joke and not seriously.
While the story written in The American Medical Weekly probably helped the phrase gain a bit of popularity in America, the phrase is apparently older. The earliest recording of it that I could find comes from the Gentlemans Magazine and Historical Chronicle, from the year 1786:
"Son of a gun. I remember to have heard this phrase frequently when a child, but as an expression rather of
good-humour than reproach."
The fact that the writer is specifically referring to the expression as a phrase, and also saying he heard the phrase as a kid, clearly suggests that the saying is even older.
* Eric, you son of a gun, I can't believe you brought me and my family out to eat at such a stunning restaurant; that was a nice thing to do.
Note: There are times where finding the origins of a phrase is not possible. Hence, in such cases of a phrase's origins being unclear, what you will see listed are plausible theories on how or from what a phrase may have originated from, but keep in mind that these are only theories and should not be taken as fact.
The quotes that I post are usually taken from newspapers or books that were written centuries ago. However, these old quotes are only to serve as an indication for how old an idiom could potentially be, and are not meant to be taken as if the phrase originated from that very source. In all likelihood, if a phrase is being quoted in a newspaper that was printed in say, the year 1838, then it's probably already commonly known at that time, meaning the origins would be older.