There is a mag for sale that proports to be a modified Mk III mag to suit the 4-5 was this ever carried out or is it just another back yarder, below copied from the fleabay ad

Lee - Enfield Conversion Magazine 10 rd. FOR No. 4 or No.5 “Was a No. 1 MK III 10 rd. Mag converted to fit the No. 4 & 5's in the late 50's”

Anyway those of you in the know will expand the knowledge of us fledglings.
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