Bullet ID

Hi - can anybody advise on what this may be? Found metal detecting in the UK. I don’t have the original item so have no explicit measurements unfortunately. Original thoughts being a type of .303 Buckingham incendiary, but neither Buster nor myself can find an exact match? Rifling is right hand twist. Any thoughts welcome. Thanks - Mark (also posted on BOCN)


Looks like an RWS Doppelkern (DK) hunting bullet