Ok, I'm a laggard. I know that. But just when I'm about to introduce the GMX to my rifle barrels up pops the CX bullet. Damn.

Hornady doesn't bother to compare / contrast (yet?) the two bullets on their website, so my SWAG is simply guilding metal vs copper alloy?

So my questions would be:
- which metal requires a higher impact velocity to perform to design? GMX or CX?
- are the two bullet designs close enough that I can use GMX load data with the CX?

And I thought my winter would be slow....

It's you and the bullet, and all the rest is secondary.