Copper plated Steel approx 18mm Cartridge

[Curious]

Hi

My son purchased a copper plated steel case which looks like it held an approximately 18mm projectile. The case is rimless, belted, the markings on the bottom are P397, 39, 7 and another symbol which I cannot see properly. Can anyone advise what this is please? Can provide photos if required.

Thanks

 

[kahu1]

From your brief description ,it sounds like a 20 x 138b 'Solothurn long' case. 20mm calibre.
Search on here with the case dimension should bring up plenty of info.

Bob

 

[Weasel]

Hi Curious,
I agree with Bob, it sounds like you have a 20 X 138b Solothurn case. The majority, but not all copper washed ones I have seen have a knurled ring about one third of the way up from the base, these were used as wooden bulleted blanks.
Welcome to the forum and best regards Weasel.

 

[Curious]

The dimensions are 138mm tall x 18.5mm projectile opening x 28.5 dia at the reinforced "belt" x 23mm dia groove x 25.5 dia before where it starts to reduce for the projectile x 105mm from base to where it starts to reduce for the projectile.

 

[Falcon]

This is a 20mm "Long Solothurn" case, which would likely have been made for use in a Flak 38 Anti-aircraft cannon. it was made in Germany in 1939.

The "P397" is a manufacturer's code, for Meta Metallwerk GmbH, Arnstadt, Thüringen, Germany.

The "39" is the year of manufacture (1939).

The "7" is a lot number.

The other symbol is likely an Eagle with an inspection number underneath.