275 rigby and 7 x 57 mauser

Are these two cartridges interchangeable?
If not ,could someone of you post a picture of the two showing their differences?

I know that Rigby was the Mauser dealer in the UK,and developed a “propietary” load for the german cartridge,but I don’t know if the cases are identical and interchangeable



Yes, they are one and the same.

IAA’s very own Jim Frigiola did a very excellant article on all of the Rigby cartridges in issue #353 of the JOURNAL.