After the fall of Berlin and Japan’s surrender, the U.S. military contracted with FN to repair, refurbish and package all the small arms used in the European theatre. More than 2.1 million American military arms made their way to FN, including M1 Garands, M1 Carbines, Thompson submachine guns, M3 “grease guns,” Browning .30-cal. and .50-cal. machine guns, as well as others.
Fabrique Nationale’s s task was to strip all components, inspect parts, check for wear and re-assemble the arms with new replacement parts (when needed) before packing and crating. The spare parts were supplied by the U.S. military or made at FN. Countless new walnut stocks were made for M1 Garands and carbines—including M1A1paratrooper stocks.
Guns were not disassembled and reassembled one at the time, instead parts were stripped and piled into large wicker baskets. No attention was paid to parts markings—only to functionality. Fabrique Nationale did not add any known markings, even some markings found on postwar M1 carbine magazines and generally attributed to FN manufacture are questionable at best. It is likely that the U.S. military specified that no markings be applied, as FN historically marked parts for quality control in its own production.
Redeployed: FN M1 Garands And Carbines | An Official Journal Of The NRA
In any event, it's a bunch of dropped M1's