The side cut outs on M1 Garand Clips are shown for comparison as some have asked. USGI and AEC Clips are of the exact same design. All Clips were manufactured with a sharp side on cut out and a more rounded side, the "inside" flat being where the clip latch actually engages to keep clip in. The outer with angle just allow clip latch to engage easier. Several examples are pictured for reference to show the side cut outs. Some incorrectly think that both sides were intended to be sharp and straight cut, not the case. The engagement "inner side" was only flat by design.
Premature clip ejection is often caused by worn Clip latch Leg or
weak Clip Latch spring not allowing the clip latch to engage the clip flat properly.