Historical Accuracy: Guns of the KV-1S

I have briefly visited this topic for 122 mm guns specifically, but since Wargaming is adding the S-34 into the mix, I’ll start from the top.

The KV-1 was king of the battlefield, enjoying comfort that the “Queen of the Desert” could only wish for. Its powerful F-32 gun, and later ZiS-5, was capable of handling any armour the enemy could throw at it. Later on, as high velocity 75 mm guns became more common and 88 mm guns became more mobile, the armour of the tank became more of a liability than an advantage. The KV-1S shaved off some of this unnecessary armour, leaving the tank largely invincible to 50 mm guns, but making it faster and more reliable. The gun remained the same. In 1942, the ZiS-5 was enough to handle nearly any threat. The ballistically identical F-34 enjoyed the same privileges. The gun was good enough, to the point that it was the “original” gun of the first IS tank (Object 233IS).

Object 233IS, or IS-1 with the 76 mm ZiS-5 gun (right).

In 1943, Tigers and Panthers started roaming the battlefield, and the 76 mm guns weren’t quite so impressive anymore. However, 85 mm guns already proved themselves worthy against these new threats. With the SU-85 already on the battlefield, IS-85 starting production, and T-34-85 already in development, why not put the good old 85 mm gun on the KV-1S? Done and done! The result was named KV-85. The first KV-85 was just an IS turret on top of a KV-1S hull. The second had a slightly enlarged turret ring and turret platform, for more comfortable operation.


When initial parts shortages stopped constricting IS-85 production, the KV-85 became obsolete. But why waste a perfectly good tank? The KV-1S already proved capable of receiving IS turrets, so it was possible to put an IS-122 turret on there. Enter, the KV-122!

However, since the whole point of the KV-85 was to serve as a buffer while IS-85 production got off the ground, there was not much of a point in the KV-122. Only one was ever built. By the way, note the muzzle brake is the late “domestic” version, not the early “German” version like in the game. This is a bona fide D-25T, not the nerfed D-2-5T. I will not discuss the KV-122 in great detail, since I already did so in this article.

If you have played the KV-1S, odds are you are familiar with these guns. However, SerB announced that, regardless of any other changes, the KV-1S will receive the S-34 gun. The what now? Let’s find out!

Grabin’s construction bureau, the one that tried to put a 107 mm gun into the IS-4 (not the Object 701, the other one), kept on going for gold, despite losing out on the first two IS tanks. This time, they hedged their bets on the 100 mm caliber. Two IS prototypes received 100 mm guns: the IS-4* (D-10) and IS-5 (S-34). The S-34 gun had all sorts of cool stuff, like a loading assist and stabilization mechanisms. You can read more about the gun and the IS tanks that carried it here. The KV isn’t mentioned anywhere, but since sticking IS turrets on KV hulls was basically second nature for the Red Army by that point, it was only a matter of time until this thing showed up.


The gun was equivalent to the D-10 in penetration (expect the same 175 mm), but had superior ergonomics, rate of fire, and accuracy. If it retains all these qualities in game, it will be a worthy successor to the D-2-5T.


Edit: I have been reminded of another project, a KV-1S (not even a KV-85) with a 122 mm howitzer.

KV-122 howitzer

The goal of the project was to combine the agility of the T-34 and firepower of the SU-122. The result was pretty impressive: the gun was capable of 6 aimed shots per minute, compared to the SU-122′s 5 shots. This was achieved by saving space inside the turret due to the smaller recoil mechanisms, compensated by the muzzle brake.

121 thoughts on “Historical Accuracy: Guns of the KV-1S

    • Depends on how the new 100mm performs in game. If it ends up buffing the KV-1s’ DPM, like some think it will, you may be wishing for that 122 to come back.

      • If you think the DPM was good from the 122m you got it all wrong mate all current t6 have more dpm than the KV1s.

        • Doesn’t matter when all you need is two shots to turn anything else at its own tier into a smoldering wreck, plus having enough accuracy to reliably hit the target (as opposed to the even more powerful KV-2, which has the disadvantage of low accuracy with the 152 mm gun), and enough pen to guarantee damage, while any other tank would require at least twice as many hits, assuming the shots don’t simply ricochet off of the upper hull or the turret.

          The main problem here, however, is how the KV-1S is still a threat even in tier VIII Battles, where it’s agile enough to be a surrogate for a medium tank but has a strong enough gun to still be a threat to a tier VIII Heavy’s flanks, something that only a handful of other vehicles can do, almost none of which being Heavies, since Heavies are supposed to suffer the most from not being top tier, as their main advantages in armor and firepower are supposed to be neutralized, while their mobility remains a handicap.

            • Yeah, that’s not the problem from where I sit, the problem is its ability to one-shot almost every tier V in the game effortlessly. The armor of similar tiered vehicles is totally outmatched by the gun, and its alpha damage is higher than any other direct fire weapon at that tier short of the KV-2′s 152mm which, as has been noted, is not just A derp gun but THE derp gun.

      • Oh yeah, that totally overpowered 152mm derp with no accuracy and three days of aim-time mounted on a very slow turret on a very slow tank?
        Totally overpowered.

        • KV-2 also has less useful armor against Tier 6-8 vehicles than KV-1S. You can only really bounce Tier 6s that don’t notice you angled correctly and thus don’t shoot gold when they should. Tier 7s and up will happily pen you anyway.

    • And if the 100mm turns out to have same pen, better accuracy, RoF, and less aimtime, in exchange for lower alpha, will you came here and complain it’s OP?

    • If it’s consistent with the 100mm on the SU-100 and fires slower, it’ll be worse than the M6 gun. The M6 already fires nearly as fast as a 100mm SU-100, with a very similar gun.

      As far as DPM, the KV-1S’s current DPM is terrible. It gets by due to high alpha. Changing the gun will almost surely improve DPM simply because 1462 DPM is not enough for a 100mm gun at tier 6.
      For reference, in order to maintain the same DPM as the 122 a 100mm gun (in patch 8.8) would need to fire 5.8 rounds per minute.
      Even the BDR fires faster.

      • My Leo Proto A has currently 1673,1 DPM (and will increase to whopping 1950 once I get the better turret).
        And couple hundred DPM less while being three tiers lower is called terrible -_-

    • 122 doesn’t even belong on the SU-100; its OP as hell. They should remove it from the 1S and the 100 because the 100mm is perfectly up to the task on the SU.

    • If they get rid of the 122mm and add the 100mm then KV-1s drivers will just go around spamming 100mm shells into the armour of any tank. So would you rather be hit continueously or just hit once and the be able to shoot the 1s several times with your gun. You would not be able to do that if he had a 100mm gun that shot almost twice as fast right?

    • The kv-1s has almost the weakest heavy tank armour of its tier. So it should get a good 122mm gun, right?

  1. Regarding those Penetrationtests with 85mm against the Tiger.

    did u know that it is mentioned even in the “tigerfibel”- some sort of user manual for the tiger- that the unagled frontal armour of tiger can be penetrated by calibers bigger than 75mm?

    its also stated that by perfect angling the armour can stop 15cm shells.
    but i think that was never really tested by soviet or western penetrationtests.

    OT. if u dont flame german tanks, ur articles are very interesting, keep upthe good work

  2. I don’t mind the KV-1S losing its 122mm. I haven’t played that, but Rees always the SU-100

      • SU-100 is perfectly fine. It doesn’t have turret. It has a lot less HP than heavies(KV-1S) It doesn’t have gun depression good as KV1-S and only one of these thing are enough for tank to be OP and KV-1S has all of them. That is the reason why you don’t see people complaining about SU-100 eventough it has the same gun and even better RoF,aimtime,accuracy.

  3. So, They will remove the OP 122mm that SerB likes and will put a gun that does have 170 less alpha, but the same pen, and its better in every other aspect?

    I dont see how this will be any nerf, its a sidegrade at best, if not a buff….

    • If that 100mm will be some kind of more accurate than 122mm – I want it on my sport :) Even after “accuracy buff” D-2-5T can badly surprise by hitting the ground few metres before the target.

      • I assume that the 100 mm S-34 gun on the KV-1S will have worse accuracy and aiming time than the 100 mm D-10T, giving the KV-1S similar disadvantages like the ARL 44 with its 90 mm DCA 45 gun.

        Hopefully, the reasonable devs at WG outvote our obviously biased SerB and remove the 122mm gun from the KV-1S.

        • In the parallel to the ARL, the 105mm it has is superior to the DCA because of the disadvantages, if the S-34 is anything like that you’ll probably find a KV-1S to still be a nasty piece of work on the battlefield.

          If it is anything BETTER than the ARL’s 105 then it’ll be sliding back into OPland

    • That’s what I worry about the most, instead of removing the 122mm they should just rebalance it. Maybe increase the reload time by a second or 2, and nerf the pen down to 160 or 150.

      • It’s not about the pen or the RoF…. it’s about that massive alpha damage paired with speed and mobility that makes this tank outstanding

          • The only time WG has ever cared about historical accuracy is for two things, if it either A) buffs the Soviets, or B) nerfs the Germans. Granted, I think SerB has a lot to do with that, because if I heard correctly SerB’s the only explicitely “Pro-Soviet/Anti-German” dev on the staff; the others, if they share his views, are much more subtle about it.

            • no.

              i think that you will find that the Germans don’t have a single production vehicle with it’s historical presets as it’s preferred load out above tier 4 (not premium)so your views are just crap.
              go whine about something else

        • I do not think tank with the 122mm is that OP in comparison to other powerful Tier 6s. I believe the problem is primarily how it steamrollers lower tier vehicles which it is matched up with more often than not. It quite often sees tanks with 40mm, 37mm and 45mm guns. It also sees tanks (I am not talking about the Brit fortress TDs) that move at a snail’s pace with their top engine. Many of these tanks are pre-war or very early war designs that were withdrawn from service because they were unable to face the 75mm guns. Having them face a faster, more armored, turreted tank with a 122mm gun is a failing in the tier system that has to be balanced evidently by replacing the gun rather than changing the MM weight.

          The KV1S has faults and it can be killed but not without a lot of luck if you are a tier or two below. High alpha is more useful than penetration, speed, DPM or armor when facing the lower tiers because you have to gut them before they can aim for a weak spot or a flank/rear. I believe that stats will show that the KV-1S is racking up way to many tier 4 and 5 kills for the balance team to be happy with.

          • Lower tier vehicles always have a problem dealing with tanks a tier or two above them, this isn’t something exclusive to the KV-1S (ie. M4 derp, KV1, Hetzer derp, all can one-shot lower tier tanks easily, Matilda is almost impervious to T3 tanks, IS-3 makes mincemeat out of T6s, etc.).

            I believe that if mm was tightened up to match the mm of some premiums (one tier spread), this game would much more balanced, and enjoyable.

            • ^Word!

              Fck the whole mathcmaking. A spread of 1 tier for *every* tank ( – aexcept scouts) and done – way better game!

            • Indeed; that’s the whole thing about any tank with an obscenely powerful gun, but the KV-1S has that, armor that basically autobounces a LOT of what will be thrown its way (whereas my AMX-40 has gone toe-to-toe with Panzer IVs, Shermans and Hetzers, and STILL won), the big problem is that it’s STILL a threat even when you’re two tiers ABOVE it, because it’s mobile enough and STILL has enough firepower that it’s a fair surrogate for a medium tank in a tier VII or tier VIII battle, and can absolutely cripple even a tier VIII Heavy, something a heavy tank two tiers LOWER should NEVER be able to do!

    • That KV-1S with a 152 mm S-41 howitzer? Its existence is debated. Svirin writes that it exists, Pasholok writes that it doesn’t, Kotin wrote in his memoirs that an IS tank had a 152 mm howitzer, but Stalin rejected it based on his opinion that a 152 mm gun is too big for a tank.

      • Funny, considered Stalin wanted more 122mm and 152mm guns on tanks. He most likely rejected it because the 122mm on IS was cheaper, easier and already effective against German tanks

  4. Maybe they should nerf the most OP tier 6 tank VK 3601 H or Hellcat…KV 1S is so easy to destroy, it is funny.

      • it depends how stupid you must be to meet 2 kv1s in front ? too bad that WG cant nerf noobs.

        • That statement shows how overpowered it is! Why shouldn’t it be a fair fight if tier 6′s meet each other, why should 1 tank be so good that other tanks have to get a tactical advantage to deal with it. It’s not like a non-noob in a KV-1S can’t also get an advantage over others as it’s not exactly a slow tank either.

            • No, it’s OP because it’s almost impossible for most opponents in its tier or below to deal with UNLESS flanking it (or sniping with a sufficiently-powerful gun and/or premium rounds), but it’s agile enough that FLANKING it is WAY harder than it needs to be.

      • It’s good enough, trust me; even in a tier VIII battle the one tank I always watch out for is the Hellcat. Why? Its camo index can make finding them INSANELY difficult, while it just pelts you with impunity while you can’t even SEE it, even if it’s barely 100 meters away.

  5. Nice article but off topic: Why isn’t this article summarised(I mean shortend like others) on homepage??

  6. S-34 100mm aside, is the 122mm gun still going to be removed or not? That 122mm gun belongs on a tier 7. It’s just overkill on tier 6.

    • Actually I could see the KV-122 as a tier VII Premium; it would be fairly balanced at that tier with only a slight HP buff to keep it competitive, since it would be comparable to a partially-upgraded IS that way.

  7. It was always upgunned the same type of tanks during the war. Interesting article. But with balance reasons, I agree with the removal of the 122mm gun, thou it is historical accurate. Duh….

  8. If I want to troll, ARL 44 with 105mm spamming gold is nastier than KV-1S, 330 alpha with 50% more rof

    • Except how many people play ARL firing gold?
      Not many. But I’m grinding the horrible AT8 at the moment and every game there are 2 or 3 kv-1s on each team racking up kills. It seems to be the nub tank of choice at the moment.

      • Oh great, you have discovered Super UV Guided AT Missle Launcher mocked up as a cannon (pre 8.6 that thing had amazing accuracy over distance, now it’s “ordinary”). The best part – normally it deals 300 damage, and fires 50% faster than KV-1S, so still a profit. And it’s way more accurate. And you have sloped 120 mm hull armor on the front, around 170 mm effective. And…
        But no oneshotting tier 4 and tier 5 TDs… NOOOOOOOOOOO!!!

      • I don’t see a different between a platoon of 105mm ARL 44 with a platoon of KV-1s, their alpha dmg are enough to rolfstomp anything

      • The reason, at least from what I think he’s trying to say and my own observations, is that WG is very…selective with their historical accuracy. They’ll abide by historical accuracy if it buffs the Soviets, nerfs the Germans, and/or helps them turn a profit.

        • That must be why any number of Germans tanks are happily driving around with guns they never had IRL – not to mention guns the Germans never actually used in tanks in the first place, notably the long 10,5cm’s.

          And why the long 88 beats the Soviet 100mm’s in penetration and matches them in damage, to speak nothing of the softstats.

      • Always thought KV-1S is OP and always claimed that. Got shitstormed many times for saying that. Finally unlocked the tank myself. Researched the modules i still haven’t via free exp so it was fully elited when i bought it. Yes, it is so bloody OP tank. It has speed, it has gun depression, it has alpha, it’s quite mobile tank and it’s armor eventough somewhat shitty on the paper is magic in practice. So many 0 dmg shots or weird bounces that can’t be achieved in any other tank. Now, most cons those whiners shitstormed at me were that it has long reload, long aiming time and crappy accuracy. Well, those are complete and utter bullshit. Accuracy? Screw accuracy after 8.6. And i can’t figure it out why that bloody KV-1S always and i mean in 99% shoots at the centere of the aiming circle while all other tanks have so many weird shots going wide. Long aiming time? Oh really? Again, can’t figure it out(yes i can but saying russian bias here causes massive shitstorms) why but with 122mm somehow you don’t even need to aim for those 3,4 seconds. Even if the circle is fully wide it shoots the dead center. Not always ofc, but you can reliably hit those important shots. So aiming time isn’t bad at all. Long reload? Well long reload indeed is long, but that can be pro by itself. You don’t have to expose your tank that much with long reload/slow RoF guns. So if KV-1S has lower alpha faster RoF gun it would need to expose itself much more to make that gun to work. With 122mm you just poke out, slam the shit out of any tank(yes even T8 tanks) and then go back to cover where you are safe to reload. And afterall those 13,xx seconds aren’t that bad at all for that kind of alpha on T6 tank. So at the end, it is horribly OP, it is horribly easy to play and horribly imbalanced for a T6 tank. It deserves the nerf and by nerf i mean realy nerf and not just geting 100mm gun that will then have amazing accuracy, amazing aim time and RoF to compensate the loss of a 122mm gun. Yes 100mm sounds like a good idea, but only if they do it with some bit of reason. Those are my two cents as an owner of the tank who claimed it’s OP and proved it’s OP.

        • If the new 100mm gun is anything like the D10T, then it won’t be have anything more than decent Rof, accuracy and aimtime.

  9. What people seem to forget, is that the soviet 100mm guns are getting an alpha buff for a RoF decrease, so even if they do remove the 122mm, You’re still going from a high alpha gun, to probably a medium-high alpha gun. It probably wont be the amount of DPM people are expecting, and then people will complain about that.

    • New soviet 100mm guns will have 250 damge so its 250vs390. KV-1s no longer 1 or 2 shots its enemies.

      • Right, but if I can squeeze off 5 shots in the same time as 2 122 shots, my dps is still going to increase, and it will have a more accurate gun and faster aim time as well. Please WG, bring on this “nerf” lol.

        • KV-1S have pretty decent DPM as is, so don’t expect that massiv an upgrade in ROF. So it will be more like slightly more then 3 shots instead of the current 2. Expect a dpm that is similar as the T-150.

        • With insane alpha it’s a lot more pleasant to play peek-a-boo than with low alpha.
          If you can trade shots 1:1 with your enemy, the 390 alpha makes you OP.

          Thus lower alpha, even with bigger DPM makes it less OP.

          And more RoF you have, more time you potentially waste between shots when compared to low RoF, high alpha. (for example when you’re peekabooing lower RoF tank).

    • Yeah but it’ll mean that the KV-1S is more or less on an equal footing with its piers in the same tier, instead of having the blatantly OP 122 mm gun that is still a threat in tier 8 battles.

  10. Hey SS, any reason this article isn’t collapsed like all others on the blog? Saw the author and wanted to skip over it, not having to scroll down through the whole thing. Thanks mate!

  11. @EE: imageshost.ru doesn’t work for us in Italy, could you re-host the picture? Anyway thanks a lot for the interesting article, personally I hope that SerB will manage to keep the 122mm gun on KV-1S but this S-34 could be an interesting alternative.

  12. On an related note, what about KV-85G? I read (from fucking wikipedia and automatic translation of aviarmor) that it’s a KV-1 with slightly modified original turret mounting a 85mm S-31 gun.

  13. “This is a bona fide D-25T, not the nerfed D-2-5T”

    Since all the Russian 122 mm guns are firing at a higher rate then their historical ones, you point is not really valid.

    You can put the D-25T on there for all I care, but give it historical fire rates and it will be a nerf anyway… the 100 mm gun would be much more in line with other tier 6 heavies, all you got to do is make sure you don’t mess up balance again by giving it higher dpm than other heavies.

    The 122 mm gun at tier 6 turns the KV-1S into a tier 6 US T30, it pops out every now and then, goes blaaahhh and knocks half your hit points off. Having higher alpha, means you don’t need to expose your tank to incoming fire as often, which negates most of the disadvantages of lower dpm.

    I play the kv-1s myself, I really like the tank, and people who say ” all you got to do is charge it when its reloading…. Trust me, I have had many medium tanks try that, I can tell you its very hard for them to kill me in 13 seconds before I shoot again. I am not just going to sit still and take shot after shot from a medium… good luck with that.

      • Yeah,fire 6 rounds per minute in is-122 and you will end killing crew by gas expelled by the gun inside the turret,practical shoots per minute in wwII for is2,where around 2,5.

        • As if such minor details had ever bothered people in a tight spot. WW1 tankers fairly regularly lost consciousness due to carbon monoxide buildups and similar fun stuff, and kept on truckin’ once they regained their senses.

          • That would be lovely. Fire your gun too much and the crew “passes out” for a few moments.
            Bit like the overheating in MWO.

    • There’s nothing historical about fire rates in WoT, it’s one of those stats devs use to balance tanks. I mean do you really think the Brits were pumping out 57mm (6-pounder gun) shells every 2 seconds?

  14. Well the fire rates for a lot of guns could be higher, like the 105 L7, but firing continuously would over heat the gun, so a RoF of 7 after the first few minutes of firing was safe.

    Like Ximet500 said, its not abuot what the gun RoF could potentially be, but what is safe.. and Russian crews dropping dead after continues shooting, yeah I am up for that ;)

    • Well, this is a fucking game you know, I doubt any Brit could manage to do what my loader on Matilda do (loading 40mm shells every 1.7 seconds for 15 minutes without breaking for a millisecond).

    • So open the hatches for better ventilation or something. Are you seriously trying to argue a tank crew “lokd in a lif und daas ströögel” wouldn’t shoot the gun as fast as they could and the situation demanded because fume buildups could be unhealthy? As opposed to what, a shell in the face or a propellant detonation?

      • I am a Brit, and I actually feel that Matilda is a bit too strong for tier 4, and I play it myself, would not mind it being nerfed.

        I feel that some tanks in this game are not well balanced, and no matter what nation tree they are in, I wont try to say its fine just because its from my nation.

        But if you want to have the KV-1S model showing the top hatch open then fine by me too.

  15. I love seeing people cry about kv-1s.

    Kv-1s one shot tier 4/5 you say? Now tell me how you fail to get behind cover in that 3.4 seconds it takes for it to aim.

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