Democratic lawmakers plan to formally reintroduce a bill Thursday that would ban military-style assault weapons and high-capacity ammunition magazines, the most ambitious — and politically risky — element of proposals unveiled by President Obama to limit gun violence.

The “Assault Weapons Ban of 2013″ is similar to one passed in 1994 that expired with little protest in 2004. The measure will be unveiled Thursday morning by a slate of Democratic co-sponsors, led by longtime gun control advocates Sen. Dianne Feinstein (Calif.) and Rep. Carolyn McCarthy (N.Y.), who have pushed for the ban before in part because of their personal histories with gun violence.