Adult Lego

can be used to either describe AR-15s or PC builds due to their high modularity.

My friend just bought a bunch of components and put it all together into a PC build, man those things are really like adult lego.
My friend just slapped a upper and lower tougher and put a red dot and 45 degree iron sights on it, building guns is like adult lego.

by F-5E Tiger II September 27, 2023

Legos for Adults

a term used by the firearms community for building out your own AR-15. Typically it means assembling the pieces of a stripped lower receiver and/or upper receiver. The components are all mil-spec are seamlessly connect with one another for a multitude of various companies and options.

"man, building your own AR really is like legos for adults, it's so fun"

by Anon930 December 7, 2020