Milt
The B(I)6 was only used by 213 Sqn, no other, the remaining Strike Sqns were equipped with B(I)8s - same gunpack though.
The gunpacks held around 500 rounds per gun which had to be fired in 3 second bursts with a min of 10 sec interval between bursts. Firing could be carried out at any speed, but not with the nose undercarriage down -
Fitting the gunpack (8s or 6s) meant changing the bomb doors. The pack was fitted in the rear of the bomb bay and the special doors had cut-outs at the rear to close snugly around the fitted pack.
These doors were bu@@ers to fit, especially if the kite had any significant fuel in No 3 Tank (airframe droop I believe). Many times, I recall, having up to a dozen blokes all sweating and heaving in an upward curve while a rigger using a hide-faced hammer, battered the 1 inch dia pip pins into the bomb door jack and pivot links, first for one door then the other. And if No 3 Tank hadn't been de-fueled you could learn a whole new set of swear words. Following that there was all the fun and games of door closing tests using the hyd hand pump (Canberra riggers have huge right arms), getting the fit around the gunpack right, then connecting the ground hyd power pump, getting the closing/opening timings right. These doors were supposed to be interchangeable but, in practice, each was marked with the no of the aircraft it fitted best, in pairs.