Proof Testing Cartridge for Mark IV Pistols

[sksvlad]

I went to New Jersey Military Vehicle Collectors Swap and got this flare proof cartridge. The previous owner put some masking tape on it and got baked. How do I remove it? I think it is paper. Was this whole thing placed inside the metallic cartridge to be fired? How did it work?

 

[kiwieod]

you could try methalayted spirits and gently rub the tape to soften it,whatever you try you will have to be very carefull of the varnished surface as it wont take much to go through

 

[sgdbdr]

What's the use of this ?