20x139 DM98A1

What is this 20x139 load? Metal projectile with a plastic cap and nose dimple.
Stamped on body: 20K DM98A1 LOS DN-10-6 DM 1257
Case headstamped: 20x139 DM100A1 LOS DN-1-881-X
The primer is stamped: 3-81. BM

How do I date these German and Dutch cases? The primer looks 1987.

20x139%20d

It is a TP-T load.
The DM98A1 was introduced at the beginning of the 1980s.
It was replaced approximately 1987 by the DM98A2/A3
Zuschneiden_4

1 Like

By contacting the manufacturer as the year is not given openly in the lot number.

Thank you both for the replies. I thought it was a TP but could not pick the tracer as the base seemed flat. I guess we use the primer date to work out years of filling. Certainly an odd secret code.

Be careful with dates on primers. They might have been installed much later or have been from previous production.
Alsdo some of these rounds were deactivated by unscrewing the primer whcih then was disposed of and people started stuffing in anything that would fit the thread.