For some reason we overlooked sporting purposes in the 2nd Amendment, but the ATF must have an extended version. However, due to popular demand, the ATF has clarified that they are not banning M855 ammunition. Good work America! Here is their official statement
On Feb. 13, 2015, ATF released for public comment a proposed framework to guide its
determination on what ammunition is "primarily intended for sporting purposes" for purposes of
granting exemptions to the Gun Control Act’s prohibition on armor piecing ammunition. The
posted framework is only a proposal, posted for the purpose of receiving public comment, and no
final determinations have been made.
Media reports have noted that the 2014 ATF Regulation Guide published online does not contain
a listing of the exemptions for armor piercing ammunition, and conclude that the absence of this
listing indicates these exemptions have been rescinded. This is not the case.
Please be advised that ATF has not rescinded any armor piercing ammunition exemption, and the
fact they are not listed in the 2014 online edition of the regulations was an error which has no
legal impact on the validity of the exemptions. The existing exemptions for armor piercing
ammunition, which apply to 5.56 mm (.223) SS 109 and M855 projectiles (identified by a green
coating on the projectile tip), and the U.S .30-06 M2AP projectile (identified by a black coating
on the projectile tip), remain in effect.
The listing of Armor Piercing Ammunition exemptions can be found in the 2005 ATF
Regulation Guide on page 166, which is posted here.
The 2014 Regulation Guide will be corrected in PDF format to include the listing of armor
piercing ammunition exemptions and posted shortly. The e-book/iBook version of the
Regulation Guide will be corrected in the near future. ATF apologizes for any confusion caused
by this publishing error.