Others in a wartime list included I compiled :

AP1641 a/c machine guns
AP1641A Vickers .303 a/c Mk. 1, 2 & 5 guns
AP1641B Vickers .303 G.O. guns
AP1641C Browning .303" a/c gun
AP1641D Lewis .303 guns
AP1641E a/c machine gun firing control mechanisms
AP1641F Hispano 20mm Mk.1 and 2 guns
AP1641G belt & magazine loading machines
AP1641H signal dischargers & signal pistols
AP1641L American machine guns
AP1641M American belt & magazine loading machines
AP1641N American a/c machine gun firing control mechanisms
AP1641P unconfirmed, probably ground defence smallarms

ch.5, which I have a poor quality photstat of, is for the S&W .38/200 revolvers