I shot some 53-grain Varmageddon / AA 2700 loads this morning. Based on what we're told here, I started out at 42.5 and had to stop at 43.25 grains where I saw some awesome accuracy potential but also signs of overpressure starting at 43.0 grains. I did not shoot anything beyond 43.25 grains (which gave me the best group of the day). Gonna try again ASAP, starting way back at 41.0 and going to 42.2 grains, 0.3 grains at a time. I was getting well over 3900 fps at 42.5 grains and see no real advantage to going beyond 43.0 grains unless that's where accuracy lives.
One thing I noticed was that barrel definitely did not heat up as quickly (I was shoot in 85-degree weather). Accuracy was not bad, just saw nothing really outstanding. I'll keep on playing with it.
Shot today.
Odd deal...the 41.0 grain load shot the first four into 0.16 inch (I'm shy one piece of brass), then the second group of five shot into 0.88 inch but with four of them going into 0.37 inch. Extreme velocity spread with that one was 172 fps (NOT a typo!). Velocity average was a touch over 3800 fps which is not bad at all, but I will not tolerate such an extreme spread. I might try that charge with a different primer, but I saw a lot of potential with the 41.9 grain charge of 2700. Five shot groups measured 0.54 and 0.58 inch...the dispersion was mostly horizontal, which I believe to be my fault. both groups superimposed would span about 0.60" except for one shot I pulled horizontally just a hair which would make the superimposed groups span about 0.75 inch, all shots included. Average velocity was 3881 fps. All this was done with Federal 210s and I plan to shoot that same load with Rem 9.5, Rem 9.5M, and Win WLRMs. Never know til you try.
The 41.0 grain charge is intriguing. I really wonder if another primer would settle it down. I guess I have to try that with the other primers, too. I'm not concerned with the 81 fps difference, just the extreme spread.
