Lancaster,
The IWK 8mm Mannlicher bullet on the right measures .323 (Starret micrometer). I have several other manufacturer brands at home that I will measure as well but suspect they will measure .323. Sure enough all bullets measured .323 dia. including a box of Mannlicher 8mm for the 1908 rifle manufactured in Austria also measured .323.

Thanks for adding the pic's for me
M4220