Cartridge : .257 Roberts +P+ (not SAAMI)
Bullet : .257, 115, Nosler BalTip 25115
Useable Case Capaci: 47.495 grain H2O = 3.084 cm³
Cartridge O.A.L. L6: 2.775 inch = 70.49 mm
Barrel Length : 22.0 inch = 558.8 mm
Powder : Hodgdon Hybrid 100V
Predicted data by increasing and decreasing the given charge,
incremented in steps of 1.136% 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
-11.4 92 39.00 2631 1767 41497 9895 98.7 1.277
-10.2 93 39.50 2663 1811 43115 9994 99.0 1.254
-09.1 94 40.00 2696 1856 44790 10086 99.3 1.232
-08.0 96 40.50 2728 1900 46532 10172 99.5 1.211
-06.8 97 41.00 2760 1946 48350 10251 99.7 1.190
-05.7 98 41.50 2792 1991 50242 10324 99.8 1.170 ! Near Maximum !
-04.5 99 42.00 2824 2037 52211 10390 99.9 1.150 ! Near Maximum !
-03.4 100 42.50 2856 2083 54252 10448 100.0 1.130 ! Near Maximum !
-02.3 102 43.00 2888 2129 56366 10499 100.0 1.111 ! Near Maximum !
-01.1 103 43.50 2919 2176 58562 10547 100.0 1.092 !DANGEROUS LOAD-DO NOT USE!
+00.0 104 44.00 2950 2223 60846 10592 100.0 1.074 !DANGEROUS LOAD-DO NOT USE!
+01.1 105 44.50 2982 2270 63222 10637 100.0 1.056 !DANGEROUS LOAD-DO NOT USE!
+02.3 106 45.00 3013 2317 65695 10681 100.0 1.038 !DANGEROUS LOAD-DO NOT USE!
+03.4 107 45.50 3043 2365 68270 10723 100.0 1.021 !DANGEROUS LOAD-DO NOT USE!
+04.5 109 46.00 3074 2413 70952 10764 100.0 1.004 !DANGEROUS LOAD-DO NOT USE!
+05.7 110 46.50 3105 2461 73747 10804 100.0 0.988 !DANGEROUS LOAD-DO NOT USE!
Results caused by ± 3% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 3% relative to nominal value:
+Ba 104 44.00 2987 2278 64602 10448 100.0 1.049 !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 3% relative to nominal value:
-Ba 104 44.00 2909 2161 57092 10747 99.9 1.102 ! Near Maximum !
