Got to the range this morning & decided to do an Optimum Charge Weight (OCW) test. These charge weights are shot round-robin style. 1 shot from charge weight one at target one, 1 shot from charge weight two at target two, etc.
6.5 Super LR, 123 Scenar jumped .025", Fed 210M, Rem brass, H4350
Rock Creek 25" 1-8 twist 5R:
charge/3-shot group size (center to center).
42.9gr/1.080"
43.2gr/0.588"
43.5gr/0.337"
43.8gr/0.163"
44.1gr/1.072"
44.4gr/1.180"
5 shots fired as sighters and to foul a clean barrel. I believe it took 7 rounds to foul and that's why you see one hole for the 42.9 and 43.2 groups near the center of the target. After those 2 rounds everything was a little high/right. I would shoot 1 round at each target for a total of 6 rounds then allow the barrel to cool. 61 degrees and DA of 1300. I didn't have a chrono today, but the first time shooting the rifle, 43.9gr of 4350 was getting 2970fps ES 9, SD 5 and shot a 0.364" group in the same area (high/right) as charges 43.5 & 43.8. I plan to work on a load somewhere between 43.5 and 43.9, am I interpreting all this correctly?
6.5 Super LR, 123 Scenar jumped .025", Fed 210M, Rem brass, H4350
Rock Creek 25" 1-8 twist 5R:
charge/3-shot group size (center to center).
42.9gr/1.080"
43.2gr/0.588"
43.5gr/0.337"
43.8gr/0.163"
44.1gr/1.072"
44.4gr/1.180"
5 shots fired as sighters and to foul a clean barrel. I believe it took 7 rounds to foul and that's why you see one hole for the 42.9 and 43.2 groups near the center of the target. After those 2 rounds everything was a little high/right. I would shoot 1 round at each target for a total of 6 rounds then allow the barrel to cool. 61 degrees and DA of 1300. I didn't have a chrono today, but the first time shooting the rifle, 43.9gr of 4350 was getting 2970fps ES 9, SD 5 and shot a 0.364" group in the same area (high/right) as charges 43.5 & 43.8. I plan to work on a load somewhere between 43.5 and 43.9, am I interpreting all this correctly?