Dirty pool.

For a long time, the ATF's interpretation of the armor-piercing handgun ammunition ban specifically exempted a pair of cartridges: 5.56mm M855 "green tip" and .30-'06 M2 "black tip". A proposed new regulation will change this, putting a stop to the commercial sale of M855 ball, currently the best source of cheap ammo to keep the AR-pattern rifles of America running. The new regulation will allow only:

Category I: .22 Caliber Projectiles
A .22 caliber projectile that otherwise would be classified as armor piercing ammunition under 18 U.S.C. 921(a)(17)(B) will be considered to be “primarily intended to be used for sporting purposes” under section 921(a)(17)(C) if the projectile weighs 40 grains or less AND is loaded into a rimfire cartridge.

Category II: All Other Caliber Projectiles
Except as provided in Category I (.22 caliber rimfire), projectiles that otherwise would be classified as armor piercing ammunition will be presumed to be “primarily intended to be used for sporting purposes” under section 921(a)(17)(C) if the projectile is loaded into a cartridge for which the only handgun that is readily available in the ordinary channels of commercial trade is a single shot handgun. ATF nevertheless retains the discretion to deny any application for a “sporting purposes” exemption if substantial evidence exists that the ammunition is not primarily intended for such purposes.

Italics mine. Please, Ohio Ordnance, do not go making any BAR "pistols" right now.

There are instructions at this linked article on how to leave a comment between now and 3/15/15, which is when the comment period for the proposed new regulation ends. Please comment.

However, please do not bother to comment if you cannot express your thoughts clearly and in a well-reasoned, somewhat spell-checked fashion. "OBMA MUSLIM FUKKR MOLAN LEBE! Come n get em! SHALL NOT BE ENFRINGED, MF'ER!" is unlikely to impress (or scare) anybody.

As the great Jewish bandito warrior poet spoke from his bathtub, "When it's time to shoot, shoot; don't talk." The corollary to that is "When it's time to talk, talk; don't shoot your mouth off."
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