Bren pistol grip screw

If you own a Mk1 Bren, here's a little bit of info that you probably weren't aware of. Have a look at the pistol grip screw and unscrew it. I nearly forgot. The two little lugs at the hammer end of the combination tool are the heavy duty forked screwdriver prongs used to unscrew the pistol grip screw. The reason that the screw head slots are segmented is this. Unscrew it and have a look inside. You'll find that it is actually hollow.

The reason for this is that originally, this hollow screw was designed to hold what was described in the first Instructions for Armourers as '..... a small reserve of oil' The bottom (now closed up, but still clearly identified between the segmented slot) was to be hollow and threaded for approx 3/4" with a coarse-ish metric thread, as yet unidentified. A small oil bottle could be inserted up, into this hollowed screw. As you'll recall, this on-board oil bottle idea was all the rage at the time with the Vickers, the Lewis, the Boys and I'm sure there'll be something else I've forgotten......

The oil bottle contained the oil and a short spoon/dipper affair, similar to that in the larger rifle oil bottle. The first 400 guns that were made for testing the machinery and evaluation were manufactured with this facility but it was withdrawn for full production. The reason for its withdrawal prior to series production was that the quantity of oil was so small as to be of no consequence and in any case, the wallet contained the oil and grease and a thicker grease for the return spring was available in a tin, carried in the chest (also withdrawn later too!)

So there it is, the reason for the hollowed pistol grip screw and the two prongs at the hammer end of the Mk1 combination tool.

Later Mk1 Brens dispensed altogether with the hollowed screw and it remained solid. Later still, for the Mk2 butt slide, the screw became a simple 1/4" diameter bolt! Now, before you put the screw and grip back. please, please, put lashings of grease around the screw to protect it from rust.

And here's another little tip learned from the canny Indian FTR Armourers. If the fine pistol grip screw thread of your Mk1 butt slide is damaged or stripped, then fear not. Simply drill a pilot hole down, through the centre of the damaged housing (don't worry, there's loads of meat....). Now drill and tap it for a suitable 1/4" BSF or UNF bolt. Now you can either plug your existing pistol grip and re-bore it to the smaller 1/4" diameter or get a replacement Mk2 pistol grip to use directly.

There, simple isn't it and saved an otherwise unserviceable butt slide too!