On the T 34s rebuilt with the Panzer III cupolas, looks like the original Russian periscope was retained. Looks like it would block the forward view port of the cupola. Am I missing something?

Short answer: No, in some cases it would block some of the view from the cupola.
Long answer: Whether the PT-4-7/PTK-5 was retained, moved, or omitted depends on the type of turret ("flat" vs. hex) and where/when the rebuild was done.
Also remember the the "periscope" was part of the F-34 gun's sighting system allowing the TC/gunner a wider field view than the telescopic sight alone. It made for faster laying of the gun on a target.

Mark

Thanks guys.

"Guys"??

Thought there was another reply prior to yours. Oops.

Mark:

Timothy actually posted his query-thread in 2 fora - HERE, and in the Armor Forum. So yes, saying "Thanks, Guys!" was sort of appropriate, as I responded in his Armor Forum, and You responded here, and there being one Timothy!

And yes, there was a response prior (at 12:28 AM) to yours!

Bob

I KNEW I'd seen another reply.

Took a few seconds of looking but found your answer.
Okay, this is getting into the minutia a bit and isn't really an answer to the initial question but I'd like to correct a couple things said in your reply.
First, whereas the PT-4-7/PTK-5 did partially interfere with the German cupola (it being their practice to point one of the vision blocks directly forward) this is not true of the Soviet version which had slits angled to either side of the periscope. (As an interesting aside the vision slits on the T-34 are not symmetrically placed. Instead they were arranged in such a way as to avoid being blocked by other turret fittings. This is true of both the -76 and -85.)
Second, to my knowledge no T-34's were assembled from parts found at either Kharkov or Stalingrad. In the case of KhPZ the factory was evacuated in its entirety; machine tools, unassembled tank parts, workers and all. (It's how Factory 183 managed to start assembling T-34s so quickly once established at Nizhni Tagil.) There was nothing left for the Nazis to work with.
Much the same is true for STZ. The Soviets made every effort to get as much as they could out of the factory before it was completely surrounded. What was left was destroyed either by the Germans or the Soviets. There was very little left there once it was captured.
That said the Nazis did set up shops specifically to rebuild captured tanks and they captured a lot of T-34s. It's one of the reasons why you see certain specific modifications over and over again (storage boxes, cupolas, tools and fixtures, and so on). Though I haven't put too much effort into their study they are interesting subjects all on their own.

Mark

2nd SS Panzer set up a rebuild shop in what was left of the KhPZ factory. http://beutepanzer.ru/Beutepanzer/su/t-34/t-34hex/das_reich7.html This plus next 5 pages. From what I gleaned there were a number of ebuild shops

Mark: With respect; You are not correcting anything -certainly nothing of import - in my reply. My point concerning both the Soviet commander's cupola and the rebuild-fitted ex-Pz.III cupola was that they were indeed fitted behind the extant periscopes, and thus they were indeed "occluded" to some degree. And thus the kits that depict this arrangement are in fact reasonably correct in doing so - which, I believe, was the point of the original query. We should note that the cupolas were used to provide sheltered general observation for the commander, and not for use as the primary gun-laying station. Some occlusion was doubtless more acceptable than the previous alternative of making the commander expose himself in order to see what the circumstances were in his vicinity.

Regarding the Germans and their assembly and / or rebuilding of T-34: As you noted, they captured quite a few of them, and they had a pretty established refurbishment and rebuilding program in place (up into 1943). Some sites claim that the Germans actually "assembled" T-34. It's no debate to me! People are sloppy in what they say - my take on it is that the Germans rebuilt T-34 in detail, and utilized salvaged and captured parts when available, but it seems mighty unlikely that they actually manufactured new T-34 from plate steel and raw castings. As in German equipment manufacture, Russian T-34 were built in final assembly plants using parts made in other plants - engines, guns, electronics, optics, rubber tires, etc. all came from other plants than those which rolled steel plates and cast turret shells, etc. There's a lot of involved industry. And yes, the Sov's evacuated as much of all that industry east as fast and as far as they could. The German nomenclature of T-34 Pz.747(r) refers to the rebuilt tanks which had been brought up to a consistent level of revision to meet German operational practices and equipment standards - as versus recent captures simply repainted and marked and sent into battle under new management.

The apparent asymmetry of slits on the Sov cupola is an interesting note - makes sense that they would know where the periscopes were on the turret roof, and even a mediocre designer would presumably avoid placing a slit right behind one, as if to achieve maximal occlusion! But do note that placing the slits so as to minimize some occlusion does not mean that vision was unobstructed - they were just doing the reasonable best they could with the limits of what else was on the roof. The Pz. III cupola was, on the other hand, not designed for the T-34 turret roof... so placing it in typical "port-forward orientation" could result in occlusion - turning it a bit (if indeed they did) may have helped reduce that effect. But either cupola beat putting one's head up and leaning around either or any of the original -34 hatch arrangements in order to see what was in front of the tank!

Sometime I'll unpack my currently stored library to delve into that Q a bit more!

Cheers! Bob

Perhaps I misunderstood what you were trying to say (if so, I apologize) and I did say that what I was writing was pretty much trivia.
As for the cupola, you did say that the both the Soviet and German cupolas were partly blocked by the periscope and its cover. In the Soviet case this is not so, it having been design specifically to avoid that. Indeed, one of the rear slits was angled so that it wouldn't be blocked by the turret vent dome. Not supposition on my part, the UTZ factory drawings still exist and show the intent clearly.
My reading also lead me to believe that it was being suggested T-34s were being assembled by the Nazis from parts left at the abandoned factories which would also be highly questionable.
So, yes. Nothing here is of earthshaking importance but things were written that were/seemed not entirely correct, at least as written in your first reply. The T-34 is kind of my core area of interest and, to be completely honest, I love debating these (pretty much) minor points.
Nothing I've written has had the intent of belittling your opinions/knowledge of the tank just to clarify what are indeed more or less minor points.

VERY interesting bit about the Sov cupola design and intent! But we may be passing like ships in a stormy night! You doubtless know a great deal more about the -34 then do I - I've collected and read a few books and a box-full of articles concerning it over the years, but... but my old brain is much more like a sieve than like a trap! I don't doubt that the Sov engineers did actually position the slits on their cupola so as to "look" in directions which were not obstructed by roof fixtures. Very practical and sensible, if I may say. But this does not mean that the commander's view out to the surrounding circumstances wasn't OBSTRUCTED. Imagine: you are sitting inside an oil-drum with one small slit in its wall. Do you consider your view of the world surrounding your drum to be obstructed, or not? The Sov's evidently positioned the slits to allow the commander his best possible views, given that there was stuff on the roof which blocked looking in some directions. Very practical and sensible. Maybe we should say that the Sov cupola design itself obstructed looking in some directions... sort of like skipping putting a window on the west side of my house, which happens to be backed right into a hill-side. My view to the west is blocked - by lack of windows that would end up looking at a hill 2 feet away from my back wall, AND by that hill itself. Pretty practical and sensible of the builder to skip the cost of putting a useless window back there! Now, in contrast, the Pz.III cupola was designed with moderately-large and wide periscopes which functionally provided reasonably good viewing 360 degrees 'round. It worked well on the tank it was designed for, which had little on the turret roof which might block viewing, but was functionally blocked in some directions on the T-34.

But it's all really trivia and interested folks kicking around (all great fun!)! Still, the bits about the Sov cupola are interesting to me - a guy much enamoured of historic bits and trivia!

PS: Do you happen to know whether the Sovs put any sort of glass or prism behind those very tiny and rather crude-looking slits in their T-34 commander's cupola? Or was it a simple, perforated can? The German cupola had an entire suite of very nice short, bullet-proof, double-prism periscopes inside - it was expensive, complex, well-made, and, along with the later "prismakoppel" cupola of later Tiger and Panther fame, a model for modern commander's cupolas.

Cheers! Bob

Not to beat a dead horse but you, well, sort of moved the goal posts there.
You wrote that the periscope partially blocked the view out of the Soviet cupola and I pointed out that, in fact, it didn't. That was the extent of my comments. I didn't speak to whether or not the view was otherwise unencumbered or the other qualities of the two cupola types.

ANYWAY, both the -76 and -85 cupolas had glass blocks backing the slits. As I recall they were triple plates of glass bonded together. The same blocks protected the turret side slits.
I have yet to crawl around a T-34-76 with the cupola but I have been in a couple of T-34-85's, One Czech and the other Soviet. You had to get your face pretty close to the block but the view was not as bad as you might guess.
Curiously, the Czech glass was very clear with just a bit of delaminating around the edges. The Soviet glass was tinted an odd amber color and were in pretty rough shape (both age related I'm pretty sure).

Mark

Thanks, Mark!

I for one love this kind of trivia! Thanks for posting.

Tankograd has a very nice book on Beute T-34s. It has some great photos.