So if you notice someone blasting away with a trench gun, and then you later become a SC Justice, it’s not within judicial notice? LOL! Good points re “common” and “unusual” weapons above, btw.
Just to clarify, in case someone doesn't understand, the term "judicial notice" is a term of legal art. It means that the court accepts a given fact as true even though there's been no sworn testimony or evidence presented to prove it.
Typically it's applied to stuff like "July 4, 1984 fell on a Wednesday," and so on. Stuff that's widely known or can be determined using widely-known, universally-accepted methods.