20 m/m projectile I/D required.

[Bockscar]

This is a 20 m/m projectile in my collection that I have been unable to identify and would appreciate any information on it if possible.
Overall the item measures 3.062" (77.79 m/m) long, has a diameter on the body of 0.780" (19.81 m/m) and a diameter over the rear copper driving band of 0.824" (20.92 m/m). The projectile is manufactured from an aluminium type alloy and has a metal band impressed in on the forward body. Manufactured in two parts that screw together, the hollow body contains a piercing penetrator weighing 84.5 Grammes, which I assume at this stage to be tungsten (or at least I hope it is!).
There are no markings on the body at all.
Have a look at the pictures and see what you think

Bockscar

 

[Chris 42 RQ]

Oerlikon ?

Would I be right in saying that the rear of the body behind the driving band is a lesser diameter than the body in front of the band-if so, that would be most likely a special contract made for use in the Oerlikon gun.

 

[Bockscar]

Chris,

Well spotted indeed! Yes, a full one millimetre down on the size given for the main body. I can say it is a rattling good fit in a Hispano case so the Oerlikon system looks good.

 

[pzgr40/42]

Hey Bockscar,

Easy enough to find out whether it is tungsten or not........... tungsten in non magnetic.

greetz,

Menno.

 

[Chris 42 RQ]

Hey Bockscar,

Easy enough to find out whether it is tungsten or not........... tungsten in non magnetic.

greetz,

Menno.

Carefull Menno !
A pure Tungsten is non magnetic but an Tungsten alloy may well be magnetic !

Alloy as in the RARDEN APFSDS Penetrator rods which are definately magnetic.
As a loose rule of thumb you can apply the fact that the purer the Tungsten the "blacker" it will appear!

 

[pzgr40/42]

Hey Chris,

Thanx !!, That's new to me, guess I could have known though. Then again......... one's never to old to learn :flute:

I've tried the magnet method on WW2 German AP cores only and found that the ones I tested deffo don't attract a magnet, but I guess I learned something today.
Thanks again.

cheers,

Menno.

 

[Bockscar]

A/P core

I actually tested the core with a magnet when I wrote my initial post but forgot to include the fact that the core does indeed attract a magnet.
I would say that the attraction is fairly strong.
Just as a matter of interest does anyone know if DU cores are magnetic?

 

[Chris 42 RQ]

No !

I actually tested the core with a magnet when I wrote my initial post but forgot to include the fact that the core does indeed attract a magnet.
I would say that the attraction is fairly strong.
Just as a matter of interest does anyone know if DU cores are magnetic?

Not even slightly as they have no Iron content.

 

[Bockscar]

D.U.

Chris,

Thanks for the info on the DU...nice to know that I havent got any of that in the house!!