Top cartridge is a 297-230
Second cartridge is a ?
Third cartridge is a 297-250
Fourth cartridge is a 250-300
The second cartridge looks like a 297-230 but it has a larger primer than any others in my collection, including blanks shorts etc. It also has a shoulder that when measured is a full 1/8" higher than any others although they vary. It will not chamber in a Belgium made single shot rifle of 297-230 caliber.
I have two of these rounds, obtained them long ago as part of another collection.
Are they just 297-230 rounds with very wide tolerance, and primer that suited the manufacturer at the time, or is there something I am missing.

I recalled that a prominent Australian collector suggested that the two rounds were 320-230 based on the old 320 long C/F, so I compared the two
and the base and primer, case length, and rim thickness are identical.
Perhaps some of the English collectors of rook rifle rounds may know more!