Just got back from the range doing a load development with CFE223 and 123gr Hornady SST's out of my 24" Overwatch. This development was done at 100 yards.
Powder range is from 30.5gr-32gr. Batteries in Chrono started failing 1/2 way through the 30.9 string and through the 31.1 string, so lost some data.
Here is what I got...
30.5 2437
30.5 2473
30.5 2460
30.5 2455
30.5 2469
Mean 2458
SD 13
30.7 2473
30.7 2469
30.7 2487
30.7 2464
30.7 2473
Mean 2473
SD 8
30.9 2473
30.9 2478
30.9 2482
30.9
30.9
Mean 2477
SD 4
31.1
31.1
31.1
31.1
31.1
31.3 2530
31.3 2539
31.3 2539
31.3 2544
31.3 2539
Mean 2538
SD 5
31.5 2578
31.5 2588
31.5 2599
31.5 2599
31.5 2599
Mean 2592
SD 8
31.7 2599
31.7 2594
31.7 2583
31.7 2574
31.7 2574
Mean 2584
SD 10
31.9 2619
31.9 2588
31.9 2583
31.9 2604
31.9 2609
Mean 2600
SD 13
32 2619
32 2629
32 2614
32 2629
32 2619
Mean 2622
SD 6
Here is the target. Very bottom target (validate sight in) was the first string of 5, 31.5 grs. Then progressed top left to bottom right. Tightest group was 31.7gr, measuring roughly .295 MOA. I made zero scope adjustments during the entire session.
Strange that the powder charge from 31.5 to 31.7 resulted in zero mean velocity gain.
Powder range is from 30.5gr-32gr. Batteries in Chrono started failing 1/2 way through the 30.9 string and through the 31.1 string, so lost some data.
Here is what I got...
30.5 2437
30.5 2473
30.5 2460
30.5 2455
30.5 2469
Mean 2458
SD 13
30.7 2473
30.7 2469
30.7 2487
30.7 2464
30.7 2473
Mean 2473
SD 8
30.9 2473
30.9 2478
30.9 2482
30.9
30.9
Mean 2477
SD 4
31.1
31.1
31.1
31.1
31.1
31.3 2530
31.3 2539
31.3 2539
31.3 2544
31.3 2539
Mean 2538
SD 5
31.5 2578
31.5 2588
31.5 2599
31.5 2599
31.5 2599
Mean 2592
SD 8
31.7 2599
31.7 2594
31.7 2583
31.7 2574
31.7 2574
Mean 2584
SD 10
31.9 2619
31.9 2588
31.9 2583
31.9 2604
31.9 2609
Mean 2600
SD 13
32 2619
32 2629
32 2614
32 2629
32 2619
Mean 2622
SD 6
Here is the target. Very bottom target (validate sight in) was the first string of 5, 31.5 grs. Then progressed top left to bottom right. Tightest group was 31.7gr, measuring roughly .295 MOA. I made zero scope adjustments during the entire session.
Strange that the powder charge from 31.5 to 31.7 resulted in zero mean velocity gain.
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