Dredging through the far corners of my grey matter; I recall being lectured back in the 80's that under this particular section 'air weapons' meant ANY air weapon i.e. this section simply doesn't apply. I'm sure the Home Office might have spotted the Tracker, Fenman etc. ! A further delve through the firearms act brings you the rule for measuring barrels. Which specifically refers to the point of explosion; reinforcing my memory.
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