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Old 09-07-2013, 09:06   #14
steve4102
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Accurate 2230 has changed over the years. It is now identical to Ramshot X-Terminator, has been since 2005.

Most published data out there is old and should not be used with the New 2230.

Use Ramshot/Accurate data, not old Lyman or Speer.

You rifle is a 5.56 and you can safely load to 5.56 chamber pressures(62K). Ramshot/Accurate have pressure tested data for the 5.56 using 2230/X-T. They list Start=22.8gr and Max= 25.3gr for both 2230 and X-t.

To answer your original question, no, there is no accurate way or formula for the handloader to measure actual pressures without pressure testing equipment.

That said there is a computer program that can calculate/guesstimate pressures and velocities for you, it's called Quickload.

Here is what QL says about your load.

Code:
 Cartridge          : .223 Rem. (SAAMI)
Bullet             : .224, 62, IMI FMJBT SS109
Cartridge O.A.L. L6: 2.225 inch or 56.52 mm
Barrel Length      : 16.0 inch or 406.4 mm
Powder             : Ramshot X-Terminator

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   76    19.52   2318     740   30787   8635     88.5    1.065
-18.0   78    20.01   2375     776   32847   8915     89.8    1.036
-16.0   80    20.50   2432     814   35018   9188     91.0    1.008
-14.0   82    20.98   2489     853   37322   9453     92.2    0.979
-12.0   84    21.47   2546     893   39776   9709     93.3    0.950
-10.0   86    21.96   2604     933   42390   9955     94.3    0.922
-08.0   87    22.45   2661     975   45173  10190     95.2    0.895
-06.0   89    22.94   2718    1017   48138  10413     96.1    0.869
-04.0   91    23.42   2775    1060   51299  10623     96.9    0.844
-02.0   93    23.91   2832    1104   54669  10819     97.6    0.819  ! Near Maximum !
+00.0   95    24.40   2888    1149   58266  10999     98.2    0.796  ! Near Maximum !
+02.0   97    24.89   2945    1194   62106  11165     98.7    0.773  !DANGEROUS LOAD-DO NOT USE!
+04.0   99    25.38   3001    1240   66209  11313     99.1    0.752  !DANGEROUS LOAD-DO NOT USE!
+06.0  101    25.86   3057    1287   70599  11444     99.5    0.731  !DANGEROUS LOAD-DO NOT USE!
+08.0  103    26.35   3113    1334   75299  11557     99.7    0.710  !DANGEROUS LOAD-DO NOT USE!
+10.0  105    26.84   3169    1382   80337  11650     99.9    0.691  !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     95    24.40   3019    1255   69078  10819    100.0    0.739  !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba     95    24.40   2713    1013   47742  10646     92.3    0.870
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