Originally Posted by
BA or bust
USA measures
- 1 short shot (also known as a jigger) = 45 millilitres = close to double the size of a UK short
UK measures
- 1 shot = 25 millilitres (Legal serving of spirits in the UK since 1985).
I think this explains why some people will feel short changed… and others a bit woozy after having the ‘same’ amount of shots! 
A proper TIL moment, thanks for sharing that! This will also explain why I used to get so spangled after just four martinis in the US.