I have a couple that aren’t really unusual but aren’t very common either. 22 Hornet and 375 H&H mag.
My mom has my dads old 32 S&W but I’ve never had the opportunity to shoot it.
.455 Wesley Mk I (self-loading not for revolvers)
8x50r Steyr Mannlicher (try finding that round)
7.62x54R in the Romanian PSL I built some years back.
Thank you, sir.Welcome to the Forum!