German 88mm Flak Gun (Stalingrad 1942)

Yes, TOS, the flak 37 version was due to replacing the old control system with the Ubertragung 37. However, according to my source (Hogg) the flak 37 was fitted with the Zielfernrohr 20 direct fire sight and also shields at the beginning of the war.

As far as RoF goes, remember the 88 was fitted with a semi-auto firing system where just shoving a round into the breech caused the breech to close and the gun to fire. During recoil the empty case was ejected and all that was needed to fire the weapon was to shove a new cartridge into the breech. Therefore the only limit (theoretically) on RoF was how quickly the crew could reload. I've seen film clips where a crew using two loaders had a gun firing close to one round a second but this may have been a propaganda stunt.

 

^I have seen many reels of German 88 crews firing at such high speeds in the North Africa campaigns.

 

So the frontline units may have had Flak 37 as well, bit of a waste as I doubt they could make full use of the improved AA fire control. One round a second looks like a propaganda stunt though it may be possible in an emergency, the crew would still need to wait for the gun to recoil back and open the breach for safety reasons and that's going to take close to one second, anything less would mean the recoil mechanism is not doing much to relieve the stress on the carriage and the 88 recoil was pretty "mild" for such a powerful gun as it was designed to be fired without lowering the base to the ground in an emergency. Possibly doable under test conditions but in the heat of battle you are going to get a lot of accidents if you play it that close, IIRC the 88 didn't even have recoil guards. IIRC the standard 7 men crew includes more than one loader so the limit probably was the speed the crew could feed ammo to the gun, so some could probably do much better then the round every four secs (15 RPM) I got. Still looking for figures on whatthe ROF would be to minimize barrel wear, probably no more than 2 RPM.
This is what I found for other German guns on on the lone sentry site (so not German figures but allied intel estimates).

Tollowing table shows the maximum rates of fire of German field guns
consistent with efficient maintenance of materiel:
[TABLE="class: grid, width: 500"]
[TR]
[TD][/TD]
[TD]Weapons Short bursts
(rounds per minute)
[/TD]
[TD]Prolonged fire
(rounds per minute)
[/TD]
[/TR]
[TR]
[TD]100-mm. gun
[/TD]
[TD="align: center"]5
[/TD]
[TD="align: center"]1 1/2
[/TD]
[/TR]
[TR]
[TD]105-mm. howitzer
[/TD]
[TD="align: center"]6
[/TD]
[TD="align: center"]2 1/2
[/TD]
[/TR]
[TR]
[TD]150-mm. howitzer
[/TD]
[TD="align: center"]4
[/TD]
[TD="align: center"]1 1/3
[/TD]
[/TR]
[/TABLE]

Not that for the long barelled "100mm gun" (K18 ?) the ratio max ROF/economical ROF is much lower, I expect something similar for the 88/56.

 

Imagine if you will, and 88 battery firing an indirect concentration of shells at an enemy infantry bn attacking their forces. Lets say 5 guns firing five rounds in, 7 seconds. Due to the high velocity of the rounds and flat trajectory there would be no warning for the infantry. If the first concentration was followed by another, this time with air bursts, it would be a tough Bn indeed that would be able to continue the attack.

As an aside I remember reading that in the PTO, our 5"/38s would sometimes be fired so fast and often that the rifling would protrude from the muzzles and firehoses would play water on the barrels to avoid cookoffs. All this with semi-fixed ammo to boot.

The schwere kanone 18 was actually 105mm. It was big for its bore size and could fire much farther than the lechte fieldhaubitze 18. Due to its increased pressure and velocity the long-term RoF would be slow to keep barrel wear within acceptable limits.