Okay, so that's a no on the 300 Mega load data. That's okay, brass will be here this week, dies next week, barrel and reamer week after that. I recently cut my 7ss Krieger barrel down to 18" from 24" to cut weight and make it easier to swing around in a small texas deer blind. Weight reduction for pack gun in Colorado. So, I was running 168 HVLD's with N560 in the 24" configuration. I was hovering around 3,000 fps comfortably. The thinner jacket, supposedly, on the hunting version of the bergers is SO dang explosive, for lack of a better word. It's not blowing up on the surface as many say (guess) it does. Mine are, at 100 yards, blowing up at about 2-3" past impact surface, neck, between shoulder and spine and spine, which is what I had hoped. The shots on spine are creating a channel through the spine.
I'm now, in the 18" configuration, running 180 Hybrids with IMR 7828SSC. I got it up to 2800 with heavy bolt at the top. I'm now backed off to 2700fps with 60.2 gr of the same. .320" 4-shot group at 100yds.
Ran out of room in cartridge with the N560, because bullets are seated into powder column for mag clearance. Short action Hawkins precision flush mag for wsm.
180 Hybrid target bullets supposedly have thicker jackets. Will do some testing on non-living objects before live testing to see how they expand.
180 HVLD's are available but like to be seated long, is reason I'm trying the hybrids (they don't mind a little, a lot in this case, jump). Will send pics when I can.