Whelen Man said:Here's a picture of the sectioned 120 compared to a heavier one. The jacket walls on the 120 are actually heavier than those on the 140 and 150 grains. I've been told that the bullet was originally intended for metallic silhouette shooting and didn't hold together well enough to drop the metallic targets at range so Nosler beefed up the case walls to help with that. It resulted in a bullet that works better than expected at high velocity. The early production was thinner walled I understand but the only ones I've had work great.