If your goal is not necessarily firearms, but you are interested in high-strength, tactical, or mechanical 3D printing, you have fantastic legal free repositories.
: While it describes itself as a repository, it has transitioned into a paid service where many files are behind a subscription. defcad files repository free
DEFCAD functions as a large search engine and web portal for 3D-printable firearm models and other CAD data. While it is known as a central repository for "3D2A" (3D-printed Second Amendment) content, its access model has shifted over time from completely free to a primarily membership-based system. Official Access and Free Files If your goal is not necessarily firearms, but
: Currently the most popular platform for hosting 3D firearm files. Many designers host their "channels" here to bypass the paywalls and censorship of traditional sites. While it is known as a central repository