300 PRC, 300 NM, 300NMI are good options. Depends on how serious you want to be. 338 will probably shine a little more. But 30’s with new bullet configurations and a good smith is definitely no slouch.
No substitute for dryness. I have hunted waterfowl in extreme conditions and packed into high country. Layering with good rain gear. I have used many brands and options and won’t mention names but I will tell you buy once and cry once and layer. You can add or subtract underneath. But good rain...
I had played with the Berger’s and the tips for 1000 yd matches. If I squared the tips I lost coefficient. I tried squaring and re tipping and still coefficient was not as good. So I tested shooting squared tips, squared tips and repointed and then took the saber tooth tips and just repointed...
My son and I shot Dashers in 1000 yd benchrest and did well. We were pushing approximately 106 grain bullets any where from 2980 to 3009 fps. Attached is a 5 shot group at a 1000 yds on testing with little wind.