USE THIS DATA AT YOUR OWN RISK.

Code
Cartridge          : 7.21 Firebird (Lazzeroni)
Bullet             : .284, 175, Nosler Accubond LR 58517 G7
Useable Case Capaci: 101.272 grain H2O = 6.575 cm³
Cartridge O.A.L. L6: 3.600 inch = 91.44 mm
Barrel Length      : 28.0 inch = 711.2 mm
Powder             : Vihtavuori N570

Predicted data by increasing and decreasing the given charge,
incremented in steps of 0.434% 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

-04.3   90    88.20   3124    3793   56359  15080     99.7    1.468
-03.9   90    88.60   3138    3828   57181  15121     99.7    1.458  ! Near Maximum !
-03.5   90    89.00   3153    3862   58015  15161     99.8    1.448  ! Near Maximum !
-03.0   91    89.40   3167    3897   58861  15198     99.8    1.438  ! Near Maximum !
-02.6   91    89.80   3181    3932   59718  15235     99.9    1.429  ! Near Maximum !
-02.2   92    90.20   3195    3967   60588  15269     99.9    1.419  ! Near Maximum !
-01.7   92    90.60   3209    4002   61469  15302     99.9    1.410  ! Near Maximum !
-01.3   92    91.00   3223    4037   62363  15334    100.0    1.400  ! Near Maximum !
-00.9   93    91.40   3237    4072   63270  15363    100.0    1.391  ! Near Maximum !
-00.4   93    91.80   3251    4107   64190  15391    100.0    1.381  ! Near Maximum !
+00.0   94    92.20   3265    4142   65122  15417    100.0    1.372  ! Near Maximum !
+00.4   94    92.60   3279    4177   66068  15442    100.0    1.363  !DANGEROUS LOAD-DO NOT USE!
+00.9   94    93.00   3293    4213   67027  15467    100.0    1.354  !DANGEROUS LOAD-DO NOT USE!
+01.3   95    93.40   3306    4248   68000  15492    100.0    1.345  !DANGEROUS LOAD-DO NOT USE!
+01.7   95    93.80   3320    4283   68987  15516    100.0    1.336  !DANGEROUS LOAD-DO NOT USE!
+02.2   96    94.20   3334    4319   69988  15541    100.0    1.327  !DANGEROUS LOAD-DO NOT USE!

Results caused by ± 5% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 5% relative to nominal value:
+Ba     94    92.20   3342    4340   72042  15091    100.0    1.312  !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 5% relative to nominal value:
-Ba     94    92.20   3170    3904   58252  15633     99.2    1.442  ! Near Maximum !

“There are three things all wise men fear: the sea in storm, a night with no moon, and the anger of a gentle man.”
― Patrick Rothfuss, The Wise Man's Fear