Please elaborate with your experience how you deem a bullet did not expand?.
When you eventually find the animal with a pencil hole through the chest/shoulders after being shot with a Barnes product, that's called not expanding. It's really not that complicated. The bullets of course are long gone but the bore diameter exit wound tells the story.
The animals were all elk with the exception of one mule deer.
LB, I have seen the old 160 TSX fail to expand myself from a 7 STW on a rib shot bull at 425. We recovered that bull and bullet (nose was bent a scosh and one petal just started to open) after a follow up and elk wandering around a bit. But haven't seen anything but good stuff from the TTSX's.
Any and all results you've seen would be excellent to hear, just to know which bullets were being used and what you saw. Not an infallible bullet out there, but man, you don't hear much bad about the TTSX's and now the LRX's either.
I'd be in the 127 LRX camp myself for elk, from the 6.5 CM to the 6.5-300 Wby. So far it seems incredibly accurate and has a decent BC onto it.
