8mm Nambu Cartridge Conversion

[Sieger]

Originally Posted by sheepherder

Here's a comparison of the two Nambu cartridges I have plus my conversion (pic attached)...

The lead-bulleted cartridge is headstamped 'W C C 6 6' and was bought from a cartridge collector at a gun show in the late 70's/early 80's for $1.00...Ed's cartridge has no markings...Mine is the 40 S&W conversion...

Lead - .407" rim .376" base .844" case 1.240" OAL .320" bullet
Ed's - .412" rim .411" base .861" case 1.244" OAL .320" bullet
Mine - .413" rim .410" base .866" case 1.246" OAL .321" bullet

The lead-bulleted cartridge has a pronounced semi-rimmed configuration...I have no idea what it actually is (original case)...I am measuring the bullet at the case mouth, it may be larger inside the neck...

Hi,

It might just be an optical, but it looks like the thickness of your rim base is substantially thicker than Ed's original. This causes the extractor damage mentioned previously. What is the original rim base thickness? What is your rim base thickness?

Sieger