Obama, ATF Seek to Ban Popular Sport Rifle Ammunition – More gun controvery is being stirred up in New York. But this time, it’s not from Gov. Andrew Cuomo. It’s President Obama, whose administration is now seeking to ban a specific type of 223-caliber bullet, known as the “green-tip.””It’s commonly used,” said Target Sports General Manager Steve Borst. “It’s the most common caliber used by Americans.” And can be found in virtually every type of rifle sold in the States. “Bolt-actions to single-shots to semi-automatic rifles,” said Borst. “It’s a very, very commonly-owned caliber. And Borst thinks the proposed ban is a violation of Second Amendment rights. “They’re taking things that have been legal and legitamately owned and making it illegal,” he said.