The most common and most likely answer to this crossword clue is the 10 letter word WINCHESTER
I've seen this crossword clue in Financial Times
W
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C
H
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More clues leading to the result WINCHESTER
- Loose screw in the firearm
- Open up northern city school
- Rifle getting short measure in cowboy film, mostly
- Wine out of case, ultimately for bottle
- See guerrilla struggle's origin in time of discontent?
- Rifle we must store in box, right?
- City game doesn’t end during season
- American producer of 1D briefly stores case for public school
- Gunnery school?
- Complex game doesn’t quite finish during the season
Buddy explains!

The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.