I read that the pzkfw III N had a pzkfw IV early turret with the short 75mm attached. Did they ever try the pzkfw IV turret with the L43 75mm on the same pzkfw III hull??

After reading several hundred pages and going over several hundred photos(with the occasional break to keep my eyes from bleeding), I see no evidence that a pz.IV turret could be used, on a pz.III. Do you remember where you read that the IV turret was mounted to a III?

The Befelspanzer III Auf K was a modified Panzer IV turret on a Panzer III hull. But the Panzer III N was the short 75 of an early Pzkpfw IV in a Panzer III turret. But it made no sense to put the 75 l/43 in the turret because you could just use Stug III or a Pzkpfw IV which were already in full production without having to go through all the development necessary to put the long gun into a Panzer III turret.

"Sturmpanzer III (Ausf.N) early production vehicle.
Previous attempts were made on the Ausf.L to adapt the turret of the Panzer IV and its gun, but they failed. Later, Daimler-Benz succeeded in equipping the Panzer III turret with a new mantlet, accommodating the short barrel 75 mm (2.95 in) already largely produced for the early versions of the Panzer IV. The early version had many differences compared to the late ones."

I am sorry, I must have been grading too many papers today. I now see my error. I was thinking Daimler succeed in the adaptation as opposed to the new mantlet.

If the L43 gun could have been adapted to the Pzkfw III it would have been traversable compared to the StugIII. The Pzkfw IV's production would not be effected and you could have extended the III's service life. Ah, what if's.

There could have been the Pz.III ausf.K, but it was deemed too problematic to redesign.

turret rings were different sizes.

The Pz.IV turret was modified to fit the Pz.3 hull, to make the Bef.Wg.III ausf. K.

This must have entailed removal of the turret floor, since the III had no turret floor nor space to fit one. The turret bearing ring may have been replaced with the III ring, I don't know. Photos of the antennas imply that both the FuG5 and Fug8 were in the hull; the visor in the turret front supports this.

David

Agreed with David the Panzer III and Panzer IV rings were of different sizes. The time and cost of making the modification compared to the benefit doesn't make sense.

I have to echo Mark and David. Up-gunning the pz.III would have been erroneous, with the pz.IV already in production. This is especially true, when you take into account Hitler's obsession, with wunderwaffen.

As mentioned, the Ausf. K command tank used a modified Panzer IV turet shell mounting a long 50 mm gun offset to one side. In the Panzer Tracts "Paper Panzers" volume, there is a drawing of a proposal for a Panzer IV turret with 75 mm L/48 gun on a Panzer III hull, but it was concluded that the chassis could not support the weight. Ir does not appear that a prototype was ever built.

The short barreled L/24 75 mm gun was fitted to a standard Panzer III turret on the Ausf. N. It was popular, as it coincided with the introduction of hollow charge (HEAT) ammunition for the gun, which could penetrate the T-34. However, production eventually halted in favor of more Sturmgeschutz production, as the L/48 gun had longer range.

I am not aware of any L24/75mm being able to take down a T-34 unless is hit it in the rear. But I been wrong before.