Section 921(a) (17) (B) ,

armor piercing ammunition as:

Chapter 44, Title 18, U.S.C. defines

The term armor piercing ammunition means a

projectile or projectile core which may be

used in a handgun and which is constructed

entirely (excluding the presence of traces

of other substances) from one or a combination

of tungsten alloys, steel, iron, brass, bronze,

beryllium copper, or depleted uranium.

Such

term does not include shotgun shot required

by federal or state environmental or game regu-

lations for hunting purposes, a frangible projec-

tile designed for target shooting, a projectile

which the Secretary finds is primarily intended

to be used for sporting purposes, or any other

projectile or projectile core which the Secretary

finds. is intended to be used for industrial

purposes, including a charge used in an oil

and gas well perforating device.

可以看出，atf將m855定義為穿甲彈