In my last post, I said that I'd recieved a rejection from The People's Friend. In my case the word count wasn't the issue, but writers have mentioned that they have been rejected for that reason. In her blog post, The People's Friend fiction editor Shirley Blair explains which word counts she is currently looking for and why work which doesn't fit these categories might be rejected.
Btw, The People Friend isn't the only womag which accepts unsolicited fiction - there are at least half a dozen more. Scroll down the page to find 'magazine guideline - quick links' for details of all the womags I'm aware of.
UPDATE 5th October 2017
Shirley Blair has more to say on this subject here.