A similar comparison is to older cars. The basic tools needed to service the older car was 7/16th spanner, a flat blade screwdriver and a hammer.
Very good.
Things got harder in 1932 when car makers started using 3/8th inch spanners. It was downhill from there. (Just as well if you had a 15bhp Austin 7).
Vintage Airguns Gallery
..Above link posted with permission from Gareth W-B In British slang an anorak is a person who has a very strong interest in niche subjects.