Copper unit test rifle, 1891 MN link in Milsurps

[diopter]

https://www.canadiangunnutz.com/for...its-test-M91-MN-rifle?p=15427477#post15427477

 

[M1-Garand]

Did they use a micrometer to measure the copper slug before and after and what determined the hardness of the copper?

 

[bigedp51]

Read the link below and at the bottom it explains pressure taking methods, make sure you read about the British base crusher method.

Cartridge Pressure Standards
http://kwk.us/pressures.html

 

[Ganderite]

Did they use a micrometer to measure the copper slug before and after and what determined the hardness of the copper?

In my youth I conducted thousands of lead (shotgun and pistol) and copper (rifle) crusher tests.

The slugs came ready made at a specific length. After the Shot, it was slipped onto a spring loaded dial gauge that was zeroed at the original length. The compression was noted and a table on the wall converted to PSI.

It was quite quick. At the end of the day I had a pail of lead or copper slugs.