Edit 15 Apr - corrected myself. The small screws on the German scopes were locking screws to prevent slipping of the turrets, not fine adjustment controls - so rather than only having coarse adjustment without their use, you cannot actually adjust the scope at all. Back to holds for the winter!
Here's something a bit different.
One thing that irks me is the way any discussion of military equipment almost always degenerates in to a pissing match about which country's piece of equipment is better. These are almost always as poorly-informed as they are annoying to be caught in the middle of, and they get exponentially worse as you approach the critical mass that is WWII German vs Soviet gear.
I've seen this argument play out twice, between the same two people, on two different forums. While I know one has a pretty heavy Soviet bias (as do I in most cases), the other in particular absolutely blew me away with how desperate he was to prove that the Germans were the best in the chosen field (in this example, optical sights and sniper equipment in general). I made it through about three or four pages before promptly losing the will to live and finding something else to read.
The point that the first party was making was basically that the Soviet PU scope was a great piece of kit and pretty much the ideal scope for a Second World War sniper. I cannot, in all honesty, fault him on his logic. I own one. The PU is built like a tank, has comparable magnification to its contemporaries despite being about half the size, and despite its lack of more cutting-edge features of the day like anti-reflection coatings on the lenses or purging of the tube with inert gas to prevent fogging or blurring of the image, it is very clear and vibrant. I can say with absolute confidence that it would be more than suitable for shooting out to ranges of 3-500 metres, with the upper end of its effective range being somewhere around 800 metres. Given that WWII was largely fought in urban centres or terrain that didn't really lend itself to 800 metre shots, and that snipers on both sides rarely did much shooting at ranges beyond half that, I would absolutely say that it is a great piece of equipment and certainly a lot better in that situation than the bigger, more sensitive German scopes, mostly derived from commercial hunting designs.
You see, the German scopes were very advanced and beautifully made, but being beautifully made meant they were costly and difficult to maintain. The fact that Germany took until 1943 to truly standardise a military scope (the ZF4, their answer to the PU which they began encountering earlier the same year) meant that German snipers who had damaged scopes had to face a logistical nightmare to obtain replacement parts. The sheer variety of types used is mind-blowing, and as a result you would want to spend over a year researching the topic before even thinking of purchasing a German sniper rifle to avoid getting hustled. The German optics were superbly clear, but they were large, difficult to adjust with gloves or in cold weather (or even in a hurry in good weather), and not easily replaced. German snipers were known to simply bypass the issue by taking captured Soviet PE and PEM-type scopes (based off of Zeiss designs, and of high quality themselves) and having unit armourers mount them on their Mauser rifles.
You see what I did there? I acknowledged the exceptional workmanship that went into German scopes, even though I consider them the inferior choice for a WWII sniper for the reasons outlined. I didn't blow them off and claim the PU did everything better, because I would be dishonest if I claimed that the PU was a better scope quality-wise than even the ZF4. It wasn't. It was cheap and easy to build, and compared to a German scope, it shows. What it was not, however, is a bad scope. For all the superior quality of the German examples, the PU was certainly clear and crisp enough to be a good medium-power sniper optic. It did not distort the image, the lenses were clear, and the scope itself was durable and simple to use. Like several of the German scopes, the PU could be removed from the rifle for maintenance and then replaced without affecting zero (the guy in question disputed this point, but I suspect he simply doesn't know how to properly mount a PU - the lower elevation screw is staked in place to ensure the scope's usual slight downwards cant is maintained every time, and the upper screw is tightened down, along with the thumbscrew. Eventually the thumbscrew may wander, but with periodic tightening that takes all of two seconds to do, the scope is not going anywhere).
It also had several other advantages which many people would have believed were disadvantages. The simple bullet drop compensator type elevation turret was graduated from 0 to 1,300m and could be turned easily with the fingers, as could the +/- 10 mils windage turret. While neither had feedback and they weren't especially precise, it seems that Soviet snipers largely used holds to correct their fire anyway, somewhat pushing these issues into irrelevance. In my honest opinion, I doubt things were much different for the Germans. Most of the German scopes had very finely calibrated adjustment turrets, some designs requiring special keys to alter them. Most of the common German scopes had very fiddly locking screws for the turrets which you absolutely would not be able to operate efficiently while wearing gloves, or trying to work fast. I would imagine that most German snipers who saw much combat would've been using holds too as a result of this, and as a result the advantage is passed back to the Soviet scope simply by virtue of lacking these (in my mind) redundant features which did little but add expense and labour during production and headaches during maintenance.
The most mind-numbingly ignorant argument, though? It came down to, and I wish I could say this was a joke, "every PU scope I have looked through has been cloudly and/or distorted the image, they are rubbish." Perhaps not in those exact words, but the words used were certainly to that effect. Now forgive me for being the voice of reason, but could it be that this guy simply looked through a lot of examples that had been poorly cared for over the past seventy years? While we're at it, when you're trying to prove which WWII sniper scope conferred the biggest advantage to its end user, why do you care what they look like seventy years after the fact? A PU that has been properly looked after may exhibit at most some very slight fogging or a slight loss of vibrance. Mine has lost a little of its colour, but the image itself is clear and not distorted at all. I have never seen a bad PU in person, though I have seen photos of abused examples, and they look no different to what would have happened if a Carl Zeiss scope had been kicked around without the proper care. These were cheap scopes intended to serve until the military no longer needed them, and they did so with distinction. Let's not introduce irrelevant arguments into the matter. At any rate, later-war German ZF4 scopes were known to vary greatly in quality from 'superb' to 'barely passable by anyone's standards', a result of slackened quality control, material shortages, and Allied bombing.
At the end of the day, I would have to argue that the PU was easily the better choice. Think about the situation; it's total war, a war of extermination, and you have a lot of snipers to equip. It should be a no-brainer, and to the very practically-minded Soviets, it was precisely that. The Germans, with no widespread 'sniper movement' to feed, continued on for quite some time before realising that the immediate future of military optics was in cheap, simple scopes that did what they were asked. No more, no less. On the other hand, for target shooting or hunting, I would not hesitate to recommend the German scopes, whose quality was absolutely unsurpassed by any other nation during the war.
Hensoldt Dialytan 4x scope, often seen mounted on Kar98k rifles. Note the tiny locking screw for the elevation wheel... now imagine it's -20 and the snow is falling sideways. Not ideal for the Eastern Front, I would say.
Looking through the Dialytan, it becomes immediately apparent that this is an excellent scope, rivalling many modern examples. The image is excellent.
Soviet PU scope, 3.5x magnification. This is my scope, built in 1944 at the Progress works (which was a microscope factory, originally, tooled up with help from Zeiss). Brutally simple and extremely hardy. The scope is deceptively heavy for its size, considering the tube and mount are built of thick machined steel. Turrets are easily adjusted with gloved hands.
A look through my PU. This scope had its lenses replace postwar, but other than the antireflective coating it is otherwise identical to its original form. Obviously the coating helps keep the image clear in bright sunlight, but I think a lot of people give it far too much stock. The dark globes apparently floating in the sky are dust specks I failed to clean up, but you can still see that despite lacking the superb glass and engineering of the German scopes... it's really not that much worse, and absolutely a serviceable mid-range sniper scope.