SD, weight retention, amount of expansion, and petal shape/sharpness all are factors. However, the first two are the ones you can most easily control. Start with a high quality controlled expansion hunting bullet with a > 0.3 SD bullet with a construction that retains near 100% of the weight, and hit at the manufacturer recommended impact velocity, and you will likely get excellent terminal performance.
I have seen very few X bullet lose petals, and those that did still got decent results. The failures I have seen with the X bullets were failures to expand. They've redesigned 3 times now to try to fix that, and I think they're still marginal in that respect. I'm not saying not to use them, but I trust the A-Frame, Northfork, and Bonded Bear Claw family softs more. I have yet to see any of the three have a bullet failure of any sort. The A-Frames and Northforks aren't the most aerodynamic, but the TAs have very good shapes.
Last edited by Llama_Bob; 10/04/21.
