I did try 1 box of Fed GMM 130g Bergers out of the RPR, but I was only shooting @ 100 yards. I think it was near round 80 after the initial break-in period, and my group size was very close to the 140g ELD-M. The ELD-M was a bit cheaper and easier to find locally when I went looking, so I settled on it for awhile. Then I tried out the Hornady 140g American Gunner with it's even better price & local availability (along with some pretty good feedback on the thread of same name here). I started to notice some misses though, which I admit, could be ALL ME. But regardless, I convinced myself to revert back and ordered a case of 140g ELD-M when a deal came up on Bud's (which is still sitting unopened due to winter conditions).
Based on what you guys have shared, it sounds like I will need to revisit Fed GMM 130g Bergers along with the Prime 130g in the Spring. (Especially in my planned push out to 1000+ yards).
Thanks Gentlemen