KV prototypes
КВ-1 с "круглой" башней
KV with V-2KF engine, looks to have been installed in one KV-1 mod 1941/42 and two KV-1S.
Tank Archives: Less Armour, More Mobility
Tank Archives: Not Quite a Swallow
Tank Archives: First KV-1S
KV-1 ZiS-22 and KV-1 F-27 (seems the F-27 was actually installed in a KV-1)
Tank Archives: Big Gun for a Small Turret (older, erroneous article with several mistakes)
https://dzen.ru/a/X6mLrIms5A2ak_hI?sid=71581699141559431 (updated article)
Tank Archives: ZiS-5 (3-K) (ignore the caption, read article above for full story)
KV-1 with F-34 (though now I’m starting to suspect it might not be an actual F-34, but again an earlier version of the ZiS-22/ZiS-5) (see above)
Про пушки для танка КВ-1 - Книга про КВ — LiveJournal
EKV
Tank Archives: Wrong Place, Wrong Time
Tank Archives: EKV Production Pitch
History of KV-3 (150, 220, 221, 222, 223) I can’t find that the 220 was called KV-3, I definitely could be wrong on that, but it was called KV-4.
https://dzen.ru/a/X_94ZP2nolPThdf2?sid=170395212105449463
Tank Archives: Mass Breakdown
https://dzen.ru/a/YMsniyPEpkwndI32?sid=170395212105449463
Tank Archives: Kirov Factory Prototypes, March 1941
IS-1 (all prototypes) referred to as IS-3
Tank Archives: IS-3, Take One
IS-2 prototype referred to as IS-3
Tank Archives: Beginnings of the D-25
IS-2 with different early muzzle brakes
Tank Archives: IS with a Heavy Gun
IS-3 prototype Kirovets-1
Tank Archives: Baby IS-3
IS-4 development history
Советский тяжелый танк ИС-4 - Maxim Viktorovich Kolomiets
Tank Archives: IS-4 Start to Finish
The T-10 being called IS-9 and IS-10 is only done by poor sources. No reputable source mentions these names. And again, they don’t even fit the timeline.
T-10MK (I can’t find anything other than forum posts talking about T-10, T-10A and T-10B command versions right now)
Танк T-10
Object 265 (again, poor sources, but all seems to point to it being armed with the M-62 making it not that interesting)
http://www.dogswar.ru/oryjeinaia-ekzotika/bronetehnika/7209-opytnyi-tank-lobekt.html
https://arsenal-info.ru/b/book/1120360644/5
Other T-10 prototypes (poor sources)
Отечественные бронированные машины 1945 – 1965 гг. . Техника и вооружение 2014 07 (transmission improvements)
http://rus-guns.com/otechestvennye-bronirovannye-mashiny-1945-1965-godov.html
Информация
T-10 with improved engines V-12-6B and V-12-6F (poor sources)
Отечественные бронированные машины 1945 – 1965 гг. . Техника и вооружение 2014 07
Информация
ZiS-25 gun project
Tank Archives: 85 mm ZiS-25
Tank Archives: ZIS-25
Tank Archives: End of the ZiS-25
OBM-51 gun project
Tank Archives: The KV's Last Bow
Tank Archives: Soviet Very High Power Guns: BL-9
Improved KV-85
Tank Archives: The KV's Last Bow
Object 752 and 777
Несчастливые три семёрки | Warspot.ru
Object 718
Object 718 - Tank Encyclopedia
85mm Strela in 278 and 770 (unknown source, and it does not list 277)
Information on the 140mm M-65GL (М-65ГЛ) smoothbore is spread across the internet, but most point back to russian wikipedia and I’m now starting to question if most of it isn’t bullshit. The project itself is historically reasonable, but I wouldn’t trust any of the information on it currently.
http://37.143.9.186/showthread.php?t=35010