The odd primer of .30-40

My friend shows a collection of the .30-40 KRAG.

But the primer of one of cartridge seemed to me the strange.

It larger than other primers and it is similar to an primer of the 8x50R Lebel

It is called a Protected Primer.

There have been several discussions of the protected primer here in the past, and their exact purpose is a bit of a mystery. You may want to perform a search for “protected” among prior postings. You will find quite a few listed.

This 30-40 was specially loaded for use in sub calibre adaptors for artillery which had a heavy fireing pin. The hole also allowed it to be used in regular rifles.

Orange is right, this is the modified 1903 type and is loaded with a 220 gr. Cole bullet.

Oddly enough, it is also seen on 8mm Murata rounds, although that was probably to protect the primer in under-barrel tube magazines.

That’s not a protected primer. It’s what orange said. The later sub-caliber cartridges used a standard primer.


What’s the difference between a Protected Primer and the one shown?


The one shown is a special re-enforced oversized primer made especially for use with the artillery firing pin. The first ones were made without the center hole which was added later so that the cartridges could be used more effectively with a rifle type firing pin in the sub-caliber device.