As a speaker of American English, the following sentences are idiomatic to me.
Don't go breaking my heart.
Don't break my heart.
The following has a different meaning from the above:
Don't go break my heart.
It is difficult to paraphrase nuance. The results are usually very wooden and stilted.
The simple imperative isn't nuanced. It is an admonition not to break my heart.
However, don't go breaking my heart means something like "Now that I have become vulnerable, don't proceed to break my heart."
The progressive, go + participle, draws subtle attention to the fact that an enabling circumstance exists from which the action might readily proceed.
Don't point that shotgun at anybody, you hear me?
Now that I've let you hold it, don't go pointing that shotgun at
anybody, you hear me?
Grandpa isn't really likely to say to his grandson "Don't go pointing that shotgun at anybody" if grandson doesn't even have his hands on the gun yet, or if Grandpa is still on the fence about whether grandson Johnny is mature enough to go a-huntin'.
If grandpa says to Johnny, "Don't you point that shotgun at anyone", an eager Johnny might not know that Grandpa has decided to let Johnny use it. But once he hears the words "Don't you go pointing that shotgun at anybody", Johnny knows the decision has been made. The circumstance that will enable him to go pointing that gun is already here, or right nigh.
Until that point, Grandpa is more likely to use the simple imperative, "Don't you point that gun at anybody." And that isn't to say he couldn't use the simple imperative beyond that point.
The third one, Don't go break my heart uses go in a different way. It doesn't mean "proceed to" or "set about to" but is the literal meaning of go. When you go where you plan to go, don't break my heart by what you do there.