What type of round/country is this casing from

[chevyfan2k9]

Pick this up today with other shell casing from a antique shop, had a couple of members leaning toward Russian but doesn't match up with head stamps I have seen, the case is 10" long below are the pics of the shell and head stamplmk what you guys think

Thanks
Jack

[bigmacglenn]

Ukrainian, Belarus?...I've got to be in the right neighborhood, lol..
Glenn

[chevyfan2k9]

Ukrainian, Belarus?...I've got to be in the right neighborhood, lol..
Glenn

Glenn, it is Russian after all but not sure what round, seen a Russian 76mm tank round with same marking had kb-4,184 and 520, maybe aa round?

[zwerge]

Looks like a Soviet 37mm M39..maybe.

[Torch]

Has the profile and rim of a bofors..licence made bofors round maybe?

[chevyfan2k9]

Looks like a Soviet 37mm M39..maybe.

That's what I was thinking to, now could this be ww2 era or post war? I been leaning towards post war but could be wrong as I am new to collecting this kind of stuff