The most common and most likely answer to this crossword clue is the 9 letter word TREBUCHET
I've seen this crossword clue in The Guardian
T
R
E
B
U
C
H
E
T
More clues leading to the result TREBUCHET
- In brief, be returning the broken missile launcher
- Weapon caused the sad end of Robert the Bruce
- I hurl stones, but three caught surprisingly
- Head of television tube: “Cher, Rolling Stones got fired from here”
- Mile off, much better to redesign old missile launcher
- Tanks beginning drive back to capture revolutionary old military machine
Buddy explains!

The straight part
We know that "I hurl stones" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case i hurl stones = trebuchet.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.
What does TREBUCHET mean?
TREBUCHET noun- A medieval siege engine consisting of a large pivoting arm heavily weighted on one end.
- A torture device for dunking suspected witches by means of a chair attached to the end of a long pole.