By comparison , 5.56 NATO and 7.62 NATO rounds cause little or no penetration to armor of that thickness .
The standard saboted tungsten ball round can pierce 9 mm of armor plate and leave a 6 mm diameter entry hole when fired from a 300 mm length barrel .
5.56 NATO and 7.62 NATO rounds cause little or no penetration to armor of that thickness .
The standard saboted tungsten ball round can pierce 9 mm of armor plate and leave a 6 mm diameter entry hole when fired from a 300 mm length barrel .