German 20 mm apit round - m601


I purchased this 20 MM cannon shell a few years ago because I thought it was unesual. It was a real pain to photograph because it is all black with some dark red stenciling so I tried many back drops for contrast. Excuse the tortoise, but its shell worked great for my camera to pick-up the red. Could not take a pic indoors. Any how, I was told that is may be German manufactured for US use? No clue! Any help would be great.


I hope you can see the RED T Shaped Markings. It was real hard capturing them in these photos.

PS: The tortoise is a primitive “ANTI MINE DEVISE”


Correct, it is made by Rheinmetall for the US.


I like the “turtle fire” cartridge.


Thanks for the ID! Much apreciated! What shoots it? Any idea? It has a different , more slender shape then most 20’s I have seen.


It was used with the M139 gun and was phased out some time ago. I think I heard that Saudi Arabia has gotten these guns from the US. If I remember correct the Saudis are getting their ammo from the Dutch now.
Here the US cartridge:

Someone else may have more or better data on hand.


The 20x139 cartridge was designed by Hispano-Suiza of Switzerland in the 1950s for the HS 820 cannon (adopted by the US Army as the M139, as mentioned). That gun is now known as the Oerlikon KAD after H-S was absorbed by Oerlikon around 1970. The ammo was also adopted for the Rheinmetall Rh202 - probably the most successful postwar ground-based 20mm cannon - and the GIAT 20M693, which is also made in South Africa as the Vektor G1-2. So it’s a very common round, available in a wide variety of loadings including APDS.

The 20x139 originated in the pre-WW2 Swiss FMK 38 aircraft/AA round, which is almost identical except for the brass case and a thinner rim.

The other European postwar 20mm round is the 20x128, developed by Oerlikon for its KAA/KAB range of cannon. It’s a different shape but performance is virtually identical. It is also used in the Spanish Meroka multibarrel naval CIWS.

The pic below is from the Ammo Photo Gallery on my website:


Amazing collection and photos of your 20 MM’s! Really appreciate that allot Tony. It is amazing the variety. I have a interesting factory display of a Primex Technologies 20 MM . I think it may be modern, not really sure? I will post a photo :-)



Here is a example of a Primex 20 MM round. I have no clue as to what it was intended to shoot or be shot from.

When I was first starting to collect this stuff as a kid, I was solely into the looks of stuff. My inert rounds had to be cool looking, shinny, have a nice shape ect. Now as I get older and my collection more diversified, I find myself being more and more fascinated by the history, design & function of these artifacts, especially after joining the IAA and this forum. Really am grateful for this platform of exchanging information. Thanks for all of your help figuring stuff out and getting a awesome history lesson. I have a crazy missile thing I am going to post in a new thread.


You’re right that it’s modern - the shape is much more aerodynamic than early projectiles.


Thanks Tony! I had a feeling it was more modern.