A little on the slow side, but if it works thats good. and you’re only burning about 96.4% of the powder charge. The second chart is run up to 62K PSI, SAAMI is 65k psi. The third chart shows you a comparison of better powders if you have any.


Cartridge : .280 Ack Imp
Bullet : .284, 162, Hornady ELD-X 2840 G7
Useable Case Capaci: 61.348 grain H2O = 3.983 cm³
Cartridge O.A.L. L6: 3.200 inch = 81.28 mm
Barrel Length : 23.0 inch = 584.2 mm
Powder : IMR 7828

Predicted data by increasing and decreasing the given charge,
incremented in steps of 2.0% of nominal charge.
CAUTION: Figures exceed maximum and minimum recommended loads !

Step Fill. Charge Vel. Energy Pmax Pmuz Prop.Burnt B_Time
% % Grains fps ft.lbs psi psi % ms

-20.0 83 45.60 2181 1711 27091 9059 83.6 1.646
-18.0 85 46.74 2239 1803 28883 9409 85.2 1.603
-16.0 87 47.88 2297 1898 30796 9753 86.7 1.561
-14.0 89 49.02 2356 1997 32843 10090 88.2 1.520
-12.0 91 50.16 2416 2099 35034 10418 89.6 1.480
-10.0 93 51.30 2475 2204 37377 10736 90.9 1.440
-08.0 95 52.44 2536 2313 39889 11043 92.2 1.395
-06.0 98 53.58 2596 2424 42584 11336 93.4 1.352
-04.0 100 54.72 2657 2539 45473 11614 94.5 1.310
-02.0 102 55.86 2718 2657 48581 11876 95.5 1.270
+00.0 104 57.00 2779 2778 51921 12120 96.4 1.231




Cartridge : .280 Ack Imp
Bullet : .284, 162, Hornady ELD-X 2840 G7
Useable Case Capaci: 61.348 grain H2O = 3.983 cm³
Cartridge O.A.L. L6: 3.200 inch = 81.28 mm
Barrel Length : 23.0 inch = 584.2 mm
Powder : IMR 7828

Predicted data by increasing and decreasing the given charge,
incremented in steps of 2.0% of nominal charge.
CAUTION: Figures exceed maximum and minimum recommended loads !

Step Fill. Charge Vel. Energy Pmax Pmuz Prop.Burnt B_Time
% % Grains fps ft.lbs psi psi % ms

-20.0 87 48.00 2303 1908 31006 9789 86.9 1.557
-18.0 90 49.20 2365 2013 33177 10143 88.4 1.514
-16.0 92 50.40 2428 2121 35514 10486 89.9 1.472
-14.0 94 51.60 2491 2232 38022 10818 91.3 1.429
-12.0 96 52.80 2555 2348 40719 11137 92.6 1.381
-10.0 98 54.00 2618 2466 43621 11440 93.8 1.337
-08.0 100 55.20 2683 2588 46754 11726 94.9 1.293
-06.0 103 56.40 2747 2714 50133 11994 95.9 1.251
-04.0 105 57.60 2811 2843 53777 12241 96.8 1.211
-02.0 107 58.80 2876 2974 57729 12466 97.6 1.172
+00.0 109 60.00 2940 3109 62006 12667 98.3 1.134


Alliant Reloder-26 101.8 61.9 4.01 2977 100.0 61000 12669 1.157
Norma MRP 102.5 60.5 3.92 2950 99.8 61000 12793 1.155
Vihtavuori N560 104.2 60.2 3.90 2940 97.8 61000 13047 1.151
Alliant Reloder-25 110.0 61.9 4.01 2935 100.0 59759 12295 1.156