But these ACI's seem to be a bit of a red herring as they pre-date the introduction of the green PLASTIC oil bottles so far as we can tell Tom. Painting the tin ones, yes. Green plastic, no! And in any case, the universal Oil OX52had replaced OIL, low cold test and others by about 1952.
Here's what I had written down about the oil cans and the CES
BOTTLE, oil, Mk 4 or IV B1/BA 0053 made of brass or Mk 5 B1/BA 6230 of black painted steel, black Bakelite or clear plastic. A part number commencing B1/BA should identify this as being originally issued for use with the rifle. According to which era the reader is interested in or the theatre in which serving, there might be 2 oil bottles in the Bren kit. The first filled with graphite grease and the second filled with Oil ‘A’ or the universal Oil OX52 or more recently, Oil OX18 the current equivalent. Nowadays, the graphite grease is carried in small tubes, usually marked ‘GREASE, Graphite, XG-340’. There are literally hundreds of makers and variations of this little bottle. The materials include black Bakelite, clear plastic and Steel. Its larger cousin, the;
CAN, oil, MG Mk3 C1/BE 6167 D.D.(E.) 1820 of 02-10-1936 or the Canadianpattern C1/CA 0901 is of a similar ilk. There are literally hundreds of manufacturers and dozens of variations including J&RO., BSM., M617 and S251. These include squared, oval, pressed steel and fabricated with soft soldered joints. The brush is retained into the lid by the leather or fibre seal. This can also found itself taken into use with the Vickers MMG kit too. Another similar can, taken from the Vickers MMG kit this time and perfectly acceptable for use with the Bren is the Can, oil, MG Mk1, C1/BD 0133. Like the oil bottle, depending on the theatre in which the gun served, there could be two oil-cans in the gun CES. The first filled with normal oil ‘A’ or the current equivalent and the second, filled with cold test oil. ACI 1356 of 9-11-40 ordered the painting of the latters cans green to differentiate them. From an examination of the CES so far, readers will see that during the life of the Bren, things have changed in many subtle ways. For a Bren enthusiast or collector setting out a CES of, say, 1970 would find it differed slightly from one of 1940.