I’m guessing the name ‘SPIT’ is related to Ramsett?
These are 303 British cases cut down, with Australian headstamps
The 303 cases are for Ramset tools. I have one in my collection. The different colour indicates the “power” level.
The .303 Ramset blanks are early made by Super Cartridge Co,Australia.
I do not know which model tool they are used in. Later ones were .38 Spl.
Very cool eye candy to collectors.