Top bullets are Hornady Dangerous Game Solids, DGS, 400 gr.

Bottom is Woodleigh Hydrostatically Stabilized 400 gr. Solids.

Hydrostatically Stabilized refers to the extrusion process and manufacturing process. The cup reportedly "cores" tissue and the pressure ring resists deflection and promotes deep, straight line penetration.

I've not shot anything yet with one of these. I've made up dummies for my gunsmith to adjust feeding from the mag. I figure if he can make these things feed smooth, everything else should be a breeze.

DF