They have a list of assault weapon features and you can't have more than 2 and no hi cap mags at all... 10 round max.
Semi-automatic, pistol grip, detachable mag, no telescoping stack, no bayonet lug, no flash suppressor or muzzle brake. is a legal rifle. Remove any of the "no" entries above and the gun is not legal.
Best to pull the NY Penal Code statute and read exactly what is and isn't legal. Don't trust me on it. Verify for yourself.