Bruce in Oz

No 4 magazine was what I was thinking.

The hole you would expect to see after removing the bayonet boss seems to me to be covered by a thin plate fixed over the whole of the front of the nosecap.

Certainly looks like an "Ishy screw" in the fore-end - so if this conversion was for mounted troops it would probably have been for service in the subcontinent rather than the Home Counties.
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