Steven King, owner of a gun supply store, shows an AR-15, 556-caliber rifle. Armor-piercing 5.56mm ammo might be outlawed by the ATF due to its capability of being fired from a handgun.

Bob Owens at the Bearing Arms site explains in further detail why M855 ammo is not, by ATF's own definition, bannable as "armor-piercing," mostly because it is mostly made of lead.

From 1986, when the law went into effect, to 2011, few manufacturers sought exemptions, and the ATF granted only two, for “green tip” 5.56 mm steel-core bullets in SS109 and M855 cartridges ...

In March 2015, more than 200 members of Congress wrote to former Alcohol, Tobacco, Firearms and Explosives (ATF) ... ATF should explain its ban on AR-15 ‘armor-piercing’ ammo by Tom Fitton, ...

WASHINGTON — Outgunned gun control advocates on Wednesday condemned a decision by the Bureau of Alcohol, Tobacco, Firearms and Explosives to back down from banning armor-piercing bullets used… ...

The original plan was to outlaw some types of armor-piercing bullets that were 5.56 mm or .223 caliber rounds; backers said if used with a handgun, they could penetrate bullet proof vests often ...

The original plan was to outlaw some types of armor-piercing bullets that were 5.56 mm or .223 caliber rounds; backers said if used with a handgun, they could penetrate bullet proof vests often ...

Ex-ATF agent Dan O’Kelly says federal law does not apply to a key component of the AR-15 and many other weapons, creating a loophole through which convicted felons could acquire a firearm piece ...

After an outcry from gun rights supporters, the Obama Administration on Tuesday dropped a plan that re-classify certain armor-piercing bullets in order to ban their sale, as the feds say they will ...

After an outcry from gun rights supporters, the Obama Administration on Tuesday dropped a plan that re-classify certain armor-piercing bullets in order to ban their sale, as the feds say they will ...