West hides vault with money for guns (3,5)

I believe the answer is:

war chest

I'm a little stuck... Click here to teach me more about this clue!

'money for guns' is the definition.
I can't judge whether this defines the answer.

'west hides vault' is the wordplay.
'hides' indicates putting letters inside.
'vault' becomes 'arch' (I've seen this in another clue).
'west' placed around 'arch' is 'WAR-CHEST'.

'with' is the link.

Can you help me to learn more?

(Other definitions for war chest that I've seen before include "funds for action?" , "Funds for a campaign" , "hypothecated funds" , "Fighting fund" , "funds for election, perhaps" .)

I've seen this clue in the Sydney Morning Herald.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.