I would like to know what the difference is between the KV1-1940 turret and the KV-1(model 1941 ) small turret or is there any difference?Any info. is appreciated.Thanks.Ted Nichols

The model year thing is a pretty vague way to delineate Soviet vehicle types, but it's a necessary evil, as the Russians often didn't bother coming up with designations for rather major changes (tracking T-34 subtypes is even messier).
The earliest KV-1 turrets had a curved rear end, and these prototype turrets sometimes turned up on production chassis (waste not, want not). These are only available in 1/35th scale as aftermarket resin items.
The first production model had the squared off "Small Turret," with the curved fillet underneath the turret bustle. It also had the short L-11 gun in the rounded mantlet. The corner joints of the early turret were mitered to 45 degree angles before welding (Trumpeter includes the gun, but you'll need to modify the turret shell yourself). The turret rear machine gun mount was a completely different design, which will have to be scratchbuilt as well.
Next, the F-32 gun in the squared off mantlet appeared, and the turret plates were butt joined, being drilled and temporarily pinned or bolted together, then welded (those are the little rings alongside the joints on the Trumpeter kits).
Then the bolted applique armor was added to this basic turret shell in early 1941, though it was discontinued after the war began.
Then the turret was redesigned without applique armor, but with a squared off fillet below the bustle overhang, and interlocked joins between the side and roof armor plates.
Then the longer Zis-5/F-34 gun appeared, as did the cast turrets.

Gerald-First.thanks for taking the time to reply.Second.thanks for all the info.regarding the turrets.I have a better understanding of what I am working with.Now I still need some help.The reason I ask about the turret differences is I just bought an MR Models KV-1 1940 turret which was designed for the Tamiya KV-1.I also purchased the Trumpeter KV-1 model 1941 small turret kit.and I was going to match them up.The problem is they will not match up.Hull and turret.My question is now,how is the Tamiya KV-1 kit and what does it need?Pe and tracks I know,but anything else?Again thanks for your time.Modeling is so much fun.Ted Nichols

hi in answer bin the tamiya kit the box is worth more than the kit. Stick with the Trumpeter and if you want any more info then email me at [email protected] , and I will send you my full article on KV 1 turret and how to modifiy them , title KV 1 cheers ian

I haven't attempted to salvage the older Tamiya kits once the newer kits by Eastern Express and Trumpeter (and now Zvezda) became available. I did a cursory comparison and found small discrepencies in the proportions of things like the engine deck main hatch and its central bulge. As I recall, the track mudguards were a bit wide compared to Trumpeter's. I'd say the two KV-1 kits have aged better than Tamiya's T-34 kits (though the KV-2 has more problems--most of the turret roof and rear details are mispositioned). Trouble is, most updates out now will be for the newer kits and may not fit the Tamiya version very well. I know you'll need to reduce the size of the sprocket teeth and change the overall width of the drive sprocket to fit any aftermarket tracks. And of course, there are plenty of motorization holes to fill with styrene stock. And a photoetch set and track set will cost more than a new Trumpeter kit, so there isn't a whole lot of incentive there to upgrade one (Trumpeter's kit needs very little--even the molded styrene engine screens don't look bad for the medium, and you can get mini photoetch sets from Eduard and Aber that just provide those at a reduced price).
I'm not sure how the MR turret "doesn't match up" to the Trumpeter hull. I've only seen a small catalog shot of the MR turret, and it looks like the beveled joint version I described. I don't know if it has the correct rear hull machine gun, but the correct joints and the correct MG mount should save you a couple of evenings of correction work on the Trumpeter turret. If you mean the turret ring is too large or too small, I'd suggest modifying it to fit. Either sand it down or shim it with sheet styrene, as needed. It would certainly be a lot less work than backdating and correcting a Tamiya KV-1E. Of course, if MR's item is very different in size from Trumpeter's, it may simply not be accurate to start with, and should be binned (the Trumpeter kits are very good overall in matching published scale drawings). I suggest you get the Tankograd books on the KV--they'll answer most all your questions, and have 1/35th scale drawings of all variants (they include a full English text--Tankograd is a German publisher, despite the name).

Terry Ashley's review on the Perth Military Modelling Site of the Trumpeter KV-1 s' Ekranami kit had some side by side photos with Tamiya's KV-1E kit.

Ian-thanks for your offer of assistance.I really appreciate that.I will contact you in the next couple of days.Sorry for the slow response,but I guess I have had my head up my ass lately.Thanks again.Ted Nichols