Fighter ammunition

Hello all ol' warriors!
Usually, it seems, most WW II-fighter aircraft which carried cannon had got 120 rounds per gun (rpg) from 1941 on, i.e. as soon as belt-fed systems were manufactured and introduced. The French Armée de l'Air started with this in June 1940 actually and the Bloch 155, an improved 152, was the first type to get it ant it was used just a little on operations before the armistice. No doubt all other French-made fighters would have followed suit quickly but the defeat on the continent prevented this from happening (too bad). The big advantage was that the ammunition jumped from 60 (with the old drum) to 120 rpg. Also, it was much easier to find room for an ammo box than for the big drum containing 60 rounds. Like the French cannon itself (Hispano-Suiza HS 404, called "Hispano") the belt feeding system was passed on to the RAF.
The Germans introduced belt-fed cannon on the Me 109 F, about January (?)-April 1941, jumping from 60 rpg to 120 too IIRC. By the way, did they adopt the French system, which was ready for use when they invaded France in June 1940, or had they already designed a teutonic system anyway?
2ND QUESTION : I think I remember some authors mentioning 200 rpg. Is this true? Was it implemented on fighters? What about bombers including the B-29?
Thanks in advance.

Imagine being the navigator, repeatedly squeezing past the pilot, carefully changing the 30kg drums for the four Hispanos whilst being thrown about the nose of a bucking and rearing Beaufighter at night in the middle of combat, frozen in a restrictive bulky flying suit, with the pilot's boots in your ear hole!

[Juha]

Nonny

the breeches of Beau's 20mm were under floor rather long way behind the pilot and rather near the navicator's post, so the navigator didn't need to squeeze past the pilot in order to reload the Hispanos. But the reloading wasn't easy especially if the Beau was twisting. So anyway the belt loading made the life much easier to Beau navigators.

Juha

[Marcelo]

The magazine for the Messerschmitt Bf-109F-2 that was the first used the belt fed heavy machine gun Mauser MG-151/15 allowed a belt of 200 round of the 15x96 ammo.
Then in the version F-4 with the introduction of the Mauser Mg-151/20 20 mm canon the capacity of the magazine descend slightly to 180 rounds, although very often even less ammo such as 150 round where loaded.

In the late G-6s/G-10/K-4 versions was also available the Reihnmetall MK-108 30 mm, for bomber hunting business, the Messers magazine only could hold 65 rounds, just enough for a 6,2 second burst of this heavy canon.

[George Hopp]

The radio/radar operator in the Bf 110 C through F also had the task of replacing the ammunition drums for the lower nose MG-FFs and MG-FF/Ms. And, once the Schrage Muzik MG-FF/Ms were installed at the rear of the crew enclosure, the rear gunner had a similar task.