Most sources list the Mosquito as having 150 rounds per cannon. Some erroneously list 300 rounds per gun due to two cannon feeding out of each ammo box, but that not being clear in some diagrams that list each box as 300 rounds. In 2000 or 2001 I had a brief correspondence with either the RAF Museum or the Imperial War Museum (I don't recall which and have long since lost the email to a hard drive death) in which they said the Mosquito had an overload of 175 rounds per cannon (and 720 rounds per machine gun, up from 500, as an overload). I forwarded this email to HTC and it may or may not be the source of the overload ammo in AH. It is entirely possible that HTC has another source, or even the same source the museum was referencing, on that.
Why bring this up again, almost a decade later? Well, in anticipation of the redone Mosquito I was reading through a bunch of my Mosquito books and I came across an interesting passage in "Mosquito" by C. Martin Sharp & Michael J. F. Bowyer, ISBN 0 947554 41 6, on page 340. It pertains to changes made to Mosquito NF.Mk IIs in order to switch them over to Intruder operations after the Intruder concept had been proven, it reads as follows:
On 10 December Air Marshal Leigh Mallory, C.-in-C. Fighter Command, visited Hatfield to report that it had been decided that Mosquitoes in his command were to adopt more offensive roles, and that the company would shortly be asked to equip some night-fighters with long range tanks enabling them to make daylight cloud-cover patrols. In December and January, 1943, this work was done on six aircraft in each of five squadrons, Nos. 25, 85, 151, 157 and 264. Radar was removed and Gee navigation equipment fitted. Twenty-mm. ammunition capacity was increased from 175 rounds to 255 rounds per gun. Thus, as 23 Squadron left, the Intruder campaign was actually to increase.
The long range tanks mentioned go were the rear of the bomb bay would have been had the Mk II had a bomb bay, this option was available and used for Mosquito Mk VIs as well. These conversions were done in Dec. of 1942 and Jan. of 1943, six months before the Mk VI entered service. In July of 1943 three squadrons, 418, 456 and 605 began using the Mk VI on Intruder missions, per page 344.
What I am now curious about is if the Mosquito Mk VI was carrying 255 rounds per gun, and if so, was it doing it right out of the production gate? Is the 150 rounds per gun, 175 rounds per gun information simply copied over from data about the F.Mk II and NF.Mk II due to sources simply saying they had the same armament? It is curious that the Beaufighter carried so much ammunition for its 20mm cannons and RAF Fighter Command required the offensive Mosquito Mk IIs to carry a similar ammunition supply and would leave the Mosquito Mk VIs with the same ammunition load of the defensive Mosquito Mk IIs.
Personally I suspect that the Mk VI carried the larger ammunition supply, but I don't have a direct quote or data to support that. I have read that the NF.Mk 30 had a capacity like that for its 20mm cannons.
Sherf, do you know anything about this?
