By late summer of 1942, the Russian GKO had to face the loss of the

- Stalingrad Tractor Plant (»STZ«), a main producer of T-34 medium tanks.
Production at the remaining plants :

- «ChKZ«, popularly »Tankograd«, at Chelyabinsk,
- «#183« plant at Nizhni Tagil,
- »#174« plant at Omsk and
- »#112«,»Krasnoye Sormovo«, at Gorkiy, was just gaining momentum and the new hexagonal cast turret didn't start without problems.

So, the GKO simply launched order #2120, that prescribed to double the production of turrets at the

- »UZTM« (Ural Heavy Machinery Plant) popularly »Uralmash« at Sverdlovsk, by October 1,1942.

Fortunately, the engineers at »Uralmash« could make use of »Shleman«, a huge 10,000-ton steel press capable of forming almost any shape required. So, as a way to accelerate production, a new slightly larger »stamped« cast turret out of 60mm hardened steel was developed with a rounded upper hexagonal shape that was simply welded onto the lower turret ring.
The result not only was faster to assemble but showed better armour protection during artillery tests as well.
Production started in October 1942, resulting in no less than 2,670 stamped turrets completed by March 1944, the last batches with the new commander copula installed.
As »Uralmash« itself only completed approx. 700 tanks in 1942/3, the majority of roughly 2,000 turrets were sent to »Tankograd« and »Krasnoye Sormovo« for assemble, resulting in the »T-34 ChTZ« as it is commonly called.
With at least three plants mounting the turrets onto their own hulls over a one-and-a-half-year period, it comes as no surprise that »Uralmash-turreted T-34« appeared in almost all imaginable flavors on the battlegrounds, including e.g.:

- early all-steel and/or late rubber wheels,
- 500mm or 550mm wide tracks of different shape,
- with or w/o external fuel tanks,
- with two long handrails or three/four short handrails,
- as flamethrower tank with the antenna attached to the turret rear.

Sources : Frontline Illustrations 1-2007 - »T-34/76 Part 2«, AirConnection - »T-34 Mythical Weapon«