<Li> 5.45 × 39mm </Li> <Li> 5.56 × 45mm NATO - Original AR - 15A2 caliber: can also safely fire . 223 Remington </Li> <Li> FN 5.7 × 28mm </Li> <Li> 6.5 mm Grendel </Li>

What caliber bullet does an ar 15 shoot