Gen Hatcher wrote of the test (Hatcher's Notebook)
The first major test the t-48 (fal) flunked in Arctic (cold weather test) where the t-44 (M14) did quite well.
A second arctic test was conducted after improvements in the FAL, where both rifles did well.
The rifles were again tested at Benning in a special "combat course test" to test the rifles to establish the performance of the rifle under very severe combat conditions, the t-48 preformed so bad the test were stopped.
The t-48 was modified by Springfield Armory based on suggestions of the British army and proved to be satisfactory.
The t-44 was chosen because it was one pound lighter and was better suited to US mass production and training standards.