From what I have heard, The Golden Sabres lost there jackets too often, so Remington changed the design to help the jacket remain with the core and this was the only change. Gel tests are fun to watch but how useful they are is up for debate. I shoot handgun bullets in freshly killed big game. This gives real life results. The only GS I retrieved from an animal was from a 380 ACP. I used it on a recently dead antelope. The bullet showed perfect expansion.