Determining velocity without a chronograph?

[Oldtrader3]

Revealing, now we are cooking! The loading manuals are all set up for the original Model 760 Rem introduction of this cartridge in 1958. They do not begin to do justice to the capabilities which are available by handloading this cartridge. It is much better than folks realise and the manuals do not show it! No wonder I was getting 3000 fps from the 160 AccuBond!

 

[SJB358]

Seems like it wouldn't be a huge trick Charlie. Even at 2900, the 160 in the 280 would be a MACK..

Cartridge : .280 Rem.
Bullet : .284, 160, Nosler AccuBond 54932
Useable Case Capaci: 58.204 grain H2O = 3.779 cm³
Cartridge O.A.L. L6: 3.330 inch = 84.58 mm
Barrel Length : 22.0 inch = 558.8 mm
Powder : IMR 7828 SSC

Predicted data by increasing and decreasing the given charge,
incremented in steps of 1.0% 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

-10.0 96 53.10 2605 2412 45437 11810 92.9 1.260
-09.0 97 53.69 2638 2473 47094 11966 93.5 1.238
-08.0 98 54.28 2671 2535 48820 12118 94.1 1.217
-07.0 100 54.87 2705 2599 50616 12264 94.6 1.197
-06.0 101 55.46 2738 2663 52486 12405 95.2 1.177
-05.0 102 56.05 2771 2728 54436 12541 95.7 1.157
-04.0 103 56.64 2804 2794 56468 12671 96.2 1.137 ! Near Maximum !
-03.0 104 57.23 2838 2861 58587 12794 96.6 1.118 ! Near Maximum !
-02.0 105 57.82 2871 2929 60798 12912 97.1 1.099 ! Near Maximum !
-01.0 106 58.41 2905 2998 63106 13024 97.5 1.080 ! Near Maximum !
+00.0 107 59.00 2938 3067 65516 13128 97.9 1.062 !DANGEROUS LOAD-DO NOT USE!
+01.0 108 59.59 2972 3138 68036 13226 98.2 1.044 !DANGEROUS LOAD-DO NOT USE!
+02.0 109 60.18 3006 3209 70669 13316 98.5 1.026 !DANGEROUS LOAD-DO NOT USE!
+03.0 110 60.77 3039 3282 73425 13399 98.8 1.009 !DANGEROUS LOAD-DO NOT USE!
+04.0 111 61.36 3073 3355 76309 13474 99.1 0.992 !DANGEROUS LOAD-DO NOT USE!
+05.0 112 61.95 3107 3429 79330 13542 99.3 0.975 !DANGEROUS LOAD-DO NOT USE!

Results caused by ± 10% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 10% relative to nominal value:
+Ba 107 59.00 3093 3400 79941 12826 100.0 0.978 !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba 107 59.00 2728 2645 53006 12594 90.6 1.170