Re: 260 rem subsonic is it worth it?
I would keep the subs to the 308. If you can only run at 1050fps, then you might as well throw as heavy of a bullet as possible. The 260 only gets you to ~140gns, where the .308 will run the 220gn round nose bullets. I run the 220's with 12.2gns of Trailboss in LC brass and any old primer. Runs a consistent 1036fps and averages 1/2 moa at 100. Flys like an anvil and hits the same. These are run through the r700 AAC with 10tw 20" bbl.