Re: 300 Win mag load advice
I shoot 200 gr Nosler ABs and 210 Berger VLDs in my 300 WM and I use IMR 7828 and H1000. I've never shot a bullet lighter than 200 gr in my 300 WM to date, but my comments are still applicable. If you strike out with 3 different 180 gr bullets, then you could always try different weight. 168s, 190s, 200s, etc.
If the gun is going to shoot well, you'll generally find a bullet/powder combination within 3 or 4 different bullets and powder combinations. I'd start to lose patience with the rifle after that.