Russian 37mm (61-K AA / NS-37 / N-37)

[Irod7]

Hello guys,

I`ve recently wrapped my head around russian 37mm ammo and oddly enough it seems that this is not very well documented on the internet.
My main question here is wether or not the ammunition uses the same bodies and has different indexes depending on what casing it is being fitted to.

For the 1939 61-K AA gun, we have


OR-167 without tracer, using MG-8 fuzes
OR-167 with tracer, using MG-37 or MG-37M fuzes (until 1967 it used the "no.5" tracer, since 1968 it used "no.9" tracer)
OR-167N with tracer, using B-37 fuzes
OZR-167 with (?) tracer, using MG-37 fuzes
BR-167 with tracer, no fuze (solid shot)

For the NS-37 air cannon we have

OZT with tracer , using ?? fuzes (probably MG-37)
BZT with tracer, no fuze (solid shot)

For the N-37 air cannon we have

OFZ without tracer, using B-37 fuze
OZT with tracer, using MG-37 or A-37 or A-37u (depending on year of production)
BZT with tracer, no fuze (solid shot)

My question here is, can we assume that OR-167 = OZT and BR-167 = BZT? Meaning that the same projectile receives a different index depending on what case it is being mated with, but essentially it is the same projectile? I have not been able to confirm this through the documents available to me.

Thanks in advance.

 

[AKON_]

37mm 61-K (AZP-39 )

OR-167N :
(drawing russian manual 1981)





--------------------------------------------------------------------------------------------------------------------------------------
37mm N-37
OFZ
OZT



37mm N-37
SSSR lizenc > ČSSR ..
(Tech doc.)



Source- NI.

Akon

 

[AKON_]

Hi Irod7
You have to confirm or refute your own working hypothesis yourself. I won't help you with that
I think you have the documents on the table.
Akon

 

[microplastic]

three data sheets (of a east german manual):

 

[Irod7]

Thanks guys for the input!

It seems that, this time, i come with the answer as well, and it comes from Christian Koll`s book "Soviet Cannon". However, the answer comes in a rather indirect form.

On page 346, when describing ammunition of the N-37, he says

The BZT projectile is identical to the armour piercing tracer projectile of the NS-37

Later, on page 361, when describing the ammunition of the NS-37, he says

The new BZT projectile was taken from the 37mm M1939 anti-aircraft gun without any changes

For the HE shells, we have the same clues.
On page 346, when describing ammunition of the N-37, we have :

The main service projectile in this calibre is the OZT shell, which was taken from the NS-37 ammunition without any changes.

Later, on page 361, when describing ammunition of the NS-37 , we have:

The OZT projectile was apparently introduced somewhat later than the OZ. It is identical to the OR-167 projectile of the 37mm anti-aircraft gun M1939

I would have two things to point out though.
The ammunition for N-37 suffered some modifications : the addition of transverse radial holes (pressure balance holes), three for the OZT and two for the BZT ammunition (change introduced in 1949), and of course the upgrading of the fuzes according to the new speeds of the aircraft (also in 1949), and the change from No.5 to No.9 tracers in 1968.
Secondly, the BZT is named rather in a strange (incorrect) way according to soviet doctrine, since it does not have any separate incendiary compound, and this fact is pointed out by Koll as well.