Nosler's philosophy is that a bullet should have some frangibility and that all of their bullets are expected, even designed to loose some lead? I am shooting 150gn in a 7x57 and 165gn in a 30-06 The BTs are suppose to loose the most weight, and are designed to operate at between 2000 and 2700 terminal velocities. They might even be considered a little "explosive." They are accurate and have a high BC due to their design. The Part is designed to open quickly (as quickly as a BT?) and might even loose the front part, but due to the design to penetrate deeply. The Solid Base, I assume, is to answer the demand to bring back a traditional cup-and-core and performs as a BT? The AB has the accuracy and BC of the BT, but due to design will hold together better, yet still loose some weight and not penetrate as much. Have I got this right? thanks, capt david :grin: :grin: :grin: