Re: retumbo in a 300wm
Are you stuck on 180s? The heavier bullets offer significant downrange advantages over the 180. If you want to use Retumbo, spend the $25 to buy a box of Berger 215s or 230s and turn that 300 WM loose.
I'm using Retumbo with 215 and 230 hybrids. The rifle loves it. I'm pushing the 215 at 2940 and the 230s at 2800 out of a 26" Rem 5r. My 215 load is 77.6 with slight crunch when seating. My 230 load is 75.5 also with slight crunch. I can only imagine the amount of compression you'd have with a 180. I could be wrong though.