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Posting here for someone that emailed me about velocity vs. barrel length because others might be interested too...
X= Bullet travel.
Add 0.86" to get barrel length from the "X" values below.
Z=Percentage of powder burned.
The more you burn, the cleaner the load.
X= Bullet travel.
Add 0.86" to get barrel length from the "X" values below.
Z=Percentage of powder burned.
The more you burn, the cleaner the load.
Code:
Cartridge : .300-221 (300 Whisper)
Bullet : .308, 208, Hornady A-MAX 30712
Cartridge O.A.L. L6: 2.200 inch or 55.88 mm
Barrel Length : 16.0 inch or 406.4 mm
Powder : Accurate 1680
Charge : 10.0 grains or 0.65 grams
Estimates of the progress of combustion:
NR.: x(in.) Z(%) v(fps) p(psi) t (ms)
67 4.73454 61.87 809.8 6380 0.9219
68 5.09024 62.87 826.4 6015 0.9582
69 5.47509 63.85 843.0 5663 0.9966
70 5.89194 64.82 859.5 5324 1.0374
71 6.34395 65.78 876.1 4998 1.0808
72 6.83467 66.72 892.7 4684 1.1271
73 7.36804 67.66 909.3 4384 1.1764
74 7.94850 68.57 925.8 4096 1.2291
75 8.58099 69.48 942.4 3821 1.2855
76 9.27110 70.37 959.0 3559 1.3460
77 10.02507 71.25 975.6 3310 1.4110
78 10.84999 72.11 992.1 3072 1.4808
79 11.75380 72.96 1008.7 2847 1.5561
80 12.74555 73.80 1025.3 2634 1.6374
81 13.83545 74.62 1041.9 2432 1.7253
82 15.03512 75.44 1058.4 2242 1.8205
83 15.11403 75.49 1059.5 2230 1.8267
84 15.13384 75.50 1059.7 2228 1.8282
85 15.13879 75.50 1059.8 2227 1.8286
86 15.14003 75.50 1059.8 2227 1.8287
87 15.14034 75.50 1059.8 2227 1.8288
Code:
Cartridge : .300-221 (300 Whisper)
Bullet : .308, 208, Hornady A-MAX 30712
Cartridge O.A.L. L6: 2.200 inch or 55.88 mm
Barrel Length : 16.0 inch or 406.4 mm
Powder : Hodgdon H110
Charge : 8.5 grains or 0.55 grams
Estimates of the progress of combustion:
NR.: x(in.) Z(%) v(fps) p(psi) t (ms)
84 5.09033 77.04 812.4 6221 1.0063
85 5.37082 77.85 825.2 5948 1.0348
86 5.66860 78.65 838.1 5681 1.0647
87 5.98498 79.43 850.9 5421 1.0959
88 6.32138 80.19 863.7 5168 1.1286
89 6.67934 80.94 876.5 4922 1.1629
90 7.06057 81.68 889.3 4683 1.1989
91 7.46691 82.40 902.1 4451 1.2367
92 7.90037 83.11 914.9 4226 1.2764
93 8.36319 83.80 927.7 4008 1.3183
94 8.85779 84.48 940.5 3797 1.3624
95 9.38683 85.14 953.3 3594 1.4090
96 9.95327 85.79 966.1 3397 1.4582
97 10.56032 86.42 978.9 3207 1.5102
98 11.21157 87.04 991.7 3025 1.5653
99 11.91096 87.65 1004.5 2849 1.6236
100 12.66283 88.24 1017.3 2681 1.6856
101 13.47202 88.82 1030.1 2519 1.7515
102 14.34389 89.38 1042.9 2364 1.8216
103 14.80516 89.65 1049.3 2289 1.8583
104 15.04248 89.79 1052.5 2252 1.8771
105 15.10252 89.83 1053.3 2242 1.8819
106 15.13265 89.84 1053.7 2238 1.8843
107 15.14019 89.85 1053.8 2237 1.8849
Code:
Cartridge : .300-221 (300 Whisper)
Bullet : .308, 208, Hornady A-MAX 30712
Cartridge O.A.L. L6: 2.200 inch or 55.88 mm
Barrel Length : 16.0 inch or 406.4 mm
Powder : Hodgdon H4198
Charge : 10.0 grains or 0.65 grams
Estimates of the progress of combustion:
NR.: x(in.) Z(%) v(fps) p(psi) t (ms)
67 5.28751 62.86 844.5 5725 0.9562
68 5.71379 63.83 861.6 5357 0.9979
69 6.17851 64.78 878.7 5005 1.0424
70 6.68584 65.73 895.8 4668 1.0900
71 7.24044 66.66 912.9 4345 1.1411
72 7.84761 67.58 930.0 4038 1.1961
73 8.51329 68.49 947.1 3746 1.2552
74 9.24427 69.38 964.2 3468 1.3189
75 10.04821 70.26 981.4 3205 1.3878
76 10.93386 71.13 998.5 2956 1.4623
77 11.91117 71.99 1015.6 2721 1.5432
78 12.99154 72.83 1032.7 2500 1.6311
79 14.18802 73.66 1049.8 2292 1.7269
80 14.83440 74.07 1058.4 2192 1.7780
81 15.00136 74.17 1060.5 2168 1.7911
82 15.08566 74.22 1061.6 2156 1.7977
83 15.12802 74.25 1062.1 2150 1.8010
84 15.13863 74.25 1062.2 2148 1.8019
85 15.13996 74.25 1062.3 2148 1.8020
86 15.14029 74.25 1062.3 2148 1.8020
