bring the bar into your legs as it passes the knees. the only way you can bang is if there is distance between the bar and your hips. by the time it reaches your hips, it should already be in light contact with your body - no collision potential.
and finish with the leg drive - you're driving your hips into it instead of stretching your body tall. extend the body in a straight line (or close to it), just leaned back as a whole to whatever degree is necessary for balance. don't push the hips through the bar.