I purchased a 275 Rigby for my 2023 Namibia hunt. The rifle is relatively old and has no serial number and the barrel is not marked with cartridge type. I bought it as a 7x57 but like calling it a 275 instead. Will I be able to travel with this firearm, are there special requirements? I've traveled internationally with firearms several times but the lack of traceability has me concerned.

The difference between genius and stupidity is that genius has its limits. Albert Einstein