The "Keep Americans Safe Act" aims to regulate large capacity ammunition feeding devices (LCAFDs) by making it unlawful to import, sell, manufacture, transfer, or possess them in interstate or foreign commerce. An LCAFD is defined as a device, such as a magazine or drum, that can hold or be readily converted to hold more than 15 rounds of ammunition, excluding certain .22 caliber rimfire devices. This legislation seeks to reduce the availability of such devices to the general public. The bill includes a grandfather clause , allowing individuals to retain LCAFDs lawfully possessed before the Act's enactment. However, it establishes specific exemptions for various entities and individuals. These include federal, state, and campus law enforcement agencies and their qualified officers, as well as retired law enforcement personnel. Further exemptions permit the use of LCAFDs by licensees under the Atomic Energy Act for nuclear facility security and by licensed manufacturers or importers for authorized testing and experimentation. To enhance accountability, any LCAFD manufactured after the bill's enactment must be marked with a serial number and date of manufacture . The legislation also amends existing law to include LCAFDs in provisions for seizure, forfeiture, and penalties for unlawful acts. Finally, the Act expands the permissible uses of Byrne Justice Assistance Grants to include funding for voluntary buy-back programs for large capacity ammunition feeding devices. This provision aims to provide a mechanism for individuals to surrender these devices. A severability clause ensures that if any part of the Act is deemed unconstitutional, the remaining provisions will remain in effect.