I tried Barnes X bullets in my Savage model 99 in ,243 Win. I loaded them rather tame, but to my surprise, they caused very high pressure so I only shot 2 out of my 20 loads. The primers were mashed totally flat, cratered, and one was pierced. I had ejection problems and nearly had stuck cases. I came home and pulled all the rest of that batch. The very same powder load in a Hornady lead core bullet, showed zero excess pressure and shot great.
That's because they are a totally different bullet. The original X was all copper and had no grooves so it was "stickier" in the bore because it had lots more contact area in the bore than lead core bullets. All of that changed with the TSX. Different alloy and grooves to lessen contact area. The TSX gives stellar accuracy, no more fouling than conventional bullets, and great terminal performance. As Memtb said, win, win, win.
