Put forward weapon, that is, an artillery piece (5,3)

I believe the answer is:

field gun

'an artillery piece' is the definition.

'put forward weapon' is the wordplay.
'put forward' becomes 'field'.
'weapon' becomes 'gun' (gun is a kind of weapon).
'field'+'gun'='FIELD GUN'

'that is' acts as a link.

I've seen this clue in The Hindu.

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