Recently had a 243 AI made, it's going to be my deer rifle. I have 2 powders on the shelf H322 and H4350. I have other powders but I want to use one of these because they are Hogden Extreme and temp stable. I have Barnes 85 grain TSX bullets. Where should I start with a load and which powder would anyone recommend to start with? or can I start with standard 243 loads and work up from them as starting points? Thanks in advance
243 AI Load Data Help Needed
- Thread starter Jeebes
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Wyo7200
Well-Known Member
I can run a QL and optimal barrel time (OBT) report for you if you can give me some information.
Case capacity in H2O,
Desired COAL
barrel length and twist
and if you chronographed those two powders- those loads (this is to adjust the burn rate to give you a more accurate estimate.
Case capacity in H2O,
Desired COAL
barrel length and twist
and if you chronographed those two powders- those loads (this is to adjust the burn rate to give you a more accurate estimate.
Wyo7200
Well-Known Member
"Where should I start with a load and which powder would anyone recommend to start with?"
I'd recommend using the slowest powder that fills the case the most. Your 24" barrel has OBT nodes in ms:
0.8160 0.8948 1.0221 1.1016 1.2282 1.3084 1.4343
Try to get within 2-3% of them and you should get excellent accuracy. The gun) is at an estimated charge that will get you on or close to a node. The third node is very high pressure and for safety, Id rather not post it- You will probably -kaboom- trying to reach the next node with H322.- We can fine tune if you get velocity data- even if its a mild charge.
"or can I start with standard 243 loads and work up from them as starting points?"
- PLEASE do not skip the safe work up procedures. Always start low and work up using published data and checking for pressure signs. Anyone reading this, please take the below as it is- estimates which may not be true in the real world. Use the below as a a reference to help you choose which powder you'd like to use.
H322:
Cartridge : .243 Ackley Imp
Bullet : .243, 85, Barnes 'TSX' BT 30212
Useable Case Capaci: 51.404 grain H2O = 3.338 cm³
Cartridge O.A.L. L6: 2.620 inch = 66.55 mm
Barrel Length : 24.0 inch = 609.6 mm
Powder : Hodgdon H322
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 65 29.70 2716 1392 33954 8283 99.6 1.348
-09.0 65 30.03 2740 1417 34770 8353 99.7 1.336
-08.0 66 30.36 2763 1441 35603 8421 99.8 1.324
-07.0 67 30.69 2787 1466 36454 8486 99.9 1.312
gun)-06.0 67 31.02 2810 1490 37323 8549 99.9 1.300gun)
-05.0 68 31.35 2833 1515 38211 8610 100.0 1.289
-04.0 69 31.68 2856 1539 39116 8667 100.0 1.277
-03.0 70 32.01 2878 1564 40041 8723 100.0 1.266
-02.0 70 32.34 2901 1589 40984 8778 100.0 1.254
-01.0 71 32.67 2924 1613 41947 8832 100.0 1.243
+00.0 72 33.00 2946 1638 42930 8887 100.0 1.232
gun)+01.0 72 33.33 2968 1663 43933 8940 100.0 1.221gun)
+02.0 73 33.66 2990 1687 44957 8994 100.0 1.211
+03.0 74 33.99 3012 1712 46001 9047 100.0 1.200
+04.0 75 34.32 3034 1737 47067 9100 100.0 1.190 ! Near Maximum !
+05.0 75 34.65 3055 1762 48154 9153 100.0 1.179 ! Near Maximum !
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 72 33.00 3035 1739 49296 8641 100.0 1.172 ! Near Maximum !
Data for burning rate decreased by 10% relative to nominal value:
-Ba 72 33.00 2814 1494 36536 9055 98.6 1.309
and H4350:
Cartridge : .243 Ackley Imp
Bullet : .243, 85, Barnes 'TSX' BT 30212
Useable Case Capaci: 51.404 grain H2O = 3.338 cm³
Cartridge O.A.L. L6: 2.620 inch = 66.55 mm
Barrel Length : 24.0 inch = 609.6 mm
Powder : Hodgdon H4350
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 80 37.08 2702 1378 33556 8936 89.2 1.352
-09.0 81 37.49 2730 1406 34477 9060 89.7 1.339
-08.0 82 37.90 2758 1435 35422 9183 90.2 1.325
-07.0 83 38.32 2786 1465 36389 9304 90.8 1.312
gun)-06.0 84 38.73 2814 1494 37377 9424 91.3 1.298gun)
-05.0 84 39.14 2842 1524 38387 9543 91.8 1.285
-04.0 85 39.55 2870 1554 39421 9660 92.2 1.273
-03.0 86 39.96 2898 1585 40477 9775 92.7 1.260
-02.0 87 40.38 2926 1616 41558 9888 93.2 1.247
-01.0 88 40.79 2954 1647 42668 10000 93.6 1.235
gun)+00.0 89 41.20 2982 1678 43808 10110 94.0 1.222gun)
+01.0 90 41.61 3010 1710 44980 10218 94.4 1.210
+02.0 91 42.02 3038 1742 46184 10323 94.8 1.198
+03.0 92 42.44 3066 1774 47420 10427 95.2 1.186 ! Near Maximum !
+04.0 92 42.85 3094 1807 48691 10528 95.6 1.174 ! Near Maximum !
+05.0 93 43.26 3122 1839 49996 10627 96.0 1.162 ! Near Maximum !
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 89 41.20 3135 1855 51016 10347 98.5 1.153 ! Near Maximum !
Data for burning rate decreased by 10% relative to nominal value:
-Ba 89 41.20 2794 1473 36641 9471 86.4 1.320
If you have any of these powders, you'd be in business:
42 loads produced a Loading Ratio below user-defined minimum of 75%. These powders have been skipped.
Powder type Filling/Loading Ratio Charge Charge Vel. Prop.Burnt P max P muzz B_Time
% Grains Gramm fps % psi psi ms
--------------------------------- -----------------------------------------------------------------
Alliant Reloder-25 100.9 47.6 3.08 3103 96.6 42806 11747 1.222
IMR 7828 98.8 45.5 2.95 3045 89.8 42543 11260 1.222
Winchester WXR 98.3 46.1 2.99 3081 92.6 43669 11495 1.222
Vihtavuori N165 98.2 46.0 2.98 3014 93.8 44485 10399 1.222
Vihtavuori N160 97.4 44.3 2.87 2979 91.2 44422 10108 1.222
Hodgdon H4831 97.1 44.7 2.90 2998 89.6 43440 10519 1.222
Accurate MAGPRO 96.3 48.5 3.14 3077 88.0 43724 11670 1.222
Ramshot Magnum 96.3 49.7 3.22 3046 93.2 43066 11163 1.222
Alliant Reloder-22 95.7 45.9 2.97 3082 92.8 43594 11501 1.222
Vihtavuori N560 95.1 46.1 2.98 3078 89.7 43177 11646 1.222
Norma MRP 94.0 46.5 3.01 3113 94.5 43331 11890 1.222
IMR 7828 SSC 93.4 45.5 2.95 3045 89.8 42543 11260 1.222
Hodgdon H4831 SC 93.4 44.7 2.90 2998 89.6 43440 10519 1.222
IMR 4831 93.0 42.2 2.73 3071 98.3 45787 10607 1.222
Alliant Reloder-19 91.9 43.6 2.82 3039 92.7 43657 10873 1.222
Winchester Supreme 780 91.8 45.9 2.97 3005 92.7 44051 10442 1.222
Hodgdon Hybrid 100V 89.7 41.1 2.67 3024 99.1 43647 10062 1.223
Hodgdon H4350 88.8 41.2 2.67 2981 94.0 43766 10106 1.223
Accurate 4350 88.8 42.1 2.73 3102 98.3 46571 10908 1.223
Ramshot Hunter 88.1 43.1 2.79 3062 96.0 44179 10907 1.222
Vihtavuori N150 87.8 39.3 2.54 2994 99.9 45304 9483 1.222
Norma URP 87.4 40.9 2.65 3051 97.7 44128 10658 1.223
Norma 204 87.3 42.7 2.77 3018 92.4 43774 10594 1.222
IMR 4350 87.2 41.1 2.66 2981 94.1 43758 10096 1.223
Vihtavuori N550 85.1 41.2 2.67 3059 97.7 44744 10757 1.223
Vihtavuori N135 84.3 36.2 2.35 2987 100.0 45965 8769 1.223
Hodgdon H414 83.2 41.7 2.70 3060 95.1 44529 10872 1.222
Winchester 760 83.2 41.7 2.70 3060 95.1 44529 10872 1.222
Accurate 2700 83.1 41.1 2.66 2952 94.6 45367 9594 1.223
IMR 4007 SSC 82.7 39.7 2.57 2991 94.6 45057 10100 1.222
Alliant Reloder-17 82.7 41.1 2.66 3077 99.1 42286 10964 1.223
Norma 203 old 82.1 39.3 2.55 3061 99.7 46452 10209 1.223
IMR 4064 81.5 36.5 2.36 2979 98.5 44146 9643 1.222
Hodgdon H380 81.1 39.3 2.54 3031 97.6 45388 10302 1.222
Hodgdon VARGET 80.6 37.0 2.40 2972 98.2 43625 9708 1.223
I'd recommend using the slowest powder that fills the case the most. Your 24" barrel has OBT nodes in ms:
0.8160 0.8948 1.0221 1.1016 1.2282 1.3084 1.4343
Try to get within 2-3% of them and you should get excellent accuracy. The gun) is at an estimated charge that will get you on or close to a node. The third node is very high pressure and for safety, Id rather not post it- You will probably -kaboom- trying to reach the next node with H322.- We can fine tune if you get velocity data- even if its a mild charge.
"or can I start with standard 243 loads and work up from them as starting points?"
- PLEASE do not skip the safe work up procedures. Always start low and work up using published data and checking for pressure signs. Anyone reading this, please take the below as it is- estimates which may not be true in the real world. Use the below as a a reference to help you choose which powder you'd like to use.
H322:
Cartridge : .243 Ackley Imp
Bullet : .243, 85, Barnes 'TSX' BT 30212
Useable Case Capaci: 51.404 grain H2O = 3.338 cm³
Cartridge O.A.L. L6: 2.620 inch = 66.55 mm
Barrel Length : 24.0 inch = 609.6 mm
Powder : Hodgdon H322
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 65 29.70 2716 1392 33954 8283 99.6 1.348
-09.0 65 30.03 2740 1417 34770 8353 99.7 1.336
-08.0 66 30.36 2763 1441 35603 8421 99.8 1.324
-07.0 67 30.69 2787 1466 36454 8486 99.9 1.312
gun)-06.0 67 31.02 2810 1490 37323 8549 99.9 1.300gun)
-05.0 68 31.35 2833 1515 38211 8610 100.0 1.289
-04.0 69 31.68 2856 1539 39116 8667 100.0 1.277
-03.0 70 32.01 2878 1564 40041 8723 100.0 1.266
-02.0 70 32.34 2901 1589 40984 8778 100.0 1.254
-01.0 71 32.67 2924 1613 41947 8832 100.0 1.243
+00.0 72 33.00 2946 1638 42930 8887 100.0 1.232
gun)+01.0 72 33.33 2968 1663 43933 8940 100.0 1.221gun)
+02.0 73 33.66 2990 1687 44957 8994 100.0 1.211
+03.0 74 33.99 3012 1712 46001 9047 100.0 1.200
+04.0 75 34.32 3034 1737 47067 9100 100.0 1.190 ! Near Maximum !
+05.0 75 34.65 3055 1762 48154 9153 100.0 1.179 ! Near Maximum !
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 72 33.00 3035 1739 49296 8641 100.0 1.172 ! Near Maximum !
Data for burning rate decreased by 10% relative to nominal value:
-Ba 72 33.00 2814 1494 36536 9055 98.6 1.309
and H4350:
Cartridge : .243 Ackley Imp
Bullet : .243, 85, Barnes 'TSX' BT 30212
Useable Case Capaci: 51.404 grain H2O = 3.338 cm³
Cartridge O.A.L. L6: 2.620 inch = 66.55 mm
Barrel Length : 24.0 inch = 609.6 mm
Powder : Hodgdon H4350
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 80 37.08 2702 1378 33556 8936 89.2 1.352
-09.0 81 37.49 2730 1406 34477 9060 89.7 1.339
-08.0 82 37.90 2758 1435 35422 9183 90.2 1.325
-07.0 83 38.32 2786 1465 36389 9304 90.8 1.312
gun)-06.0 84 38.73 2814 1494 37377 9424 91.3 1.298gun)
-05.0 84 39.14 2842 1524 38387 9543 91.8 1.285
-04.0 85 39.55 2870 1554 39421 9660 92.2 1.273
-03.0 86 39.96 2898 1585 40477 9775 92.7 1.260
-02.0 87 40.38 2926 1616 41558 9888 93.2 1.247
-01.0 88 40.79 2954 1647 42668 10000 93.6 1.235
gun)+00.0 89 41.20 2982 1678 43808 10110 94.0 1.222gun)
+01.0 90 41.61 3010 1710 44980 10218 94.4 1.210
+02.0 91 42.02 3038 1742 46184 10323 94.8 1.198
+03.0 92 42.44 3066 1774 47420 10427 95.2 1.186 ! Near Maximum !
+04.0 92 42.85 3094 1807 48691 10528 95.6 1.174 ! Near Maximum !
+05.0 93 43.26 3122 1839 49996 10627 96.0 1.162 ! Near Maximum !
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 89 41.20 3135 1855 51016 10347 98.5 1.153 ! Near Maximum !
Data for burning rate decreased by 10% relative to nominal value:
-Ba 89 41.20 2794 1473 36641 9471 86.4 1.320
If you have any of these powders, you'd be in business:
42 loads produced a Loading Ratio below user-defined minimum of 75%. These powders have been skipped.
Powder type Filling/Loading Ratio Charge Charge Vel. Prop.Burnt P max P muzz B_Time
% Grains Gramm fps % psi psi ms
--------------------------------- -----------------------------------------------------------------
Alliant Reloder-25 100.9 47.6 3.08 3103 96.6 42806 11747 1.222
IMR 7828 98.8 45.5 2.95 3045 89.8 42543 11260 1.222
Winchester WXR 98.3 46.1 2.99 3081 92.6 43669 11495 1.222
Vihtavuori N165 98.2 46.0 2.98 3014 93.8 44485 10399 1.222
Vihtavuori N160 97.4 44.3 2.87 2979 91.2 44422 10108 1.222
Hodgdon H4831 97.1 44.7 2.90 2998 89.6 43440 10519 1.222
Accurate MAGPRO 96.3 48.5 3.14 3077 88.0 43724 11670 1.222
Ramshot Magnum 96.3 49.7 3.22 3046 93.2 43066 11163 1.222
Alliant Reloder-22 95.7 45.9 2.97 3082 92.8 43594 11501 1.222
Vihtavuori N560 95.1 46.1 2.98 3078 89.7 43177 11646 1.222
Norma MRP 94.0 46.5 3.01 3113 94.5 43331 11890 1.222
IMR 7828 SSC 93.4 45.5 2.95 3045 89.8 42543 11260 1.222
Hodgdon H4831 SC 93.4 44.7 2.90 2998 89.6 43440 10519 1.222
IMR 4831 93.0 42.2 2.73 3071 98.3 45787 10607 1.222
Alliant Reloder-19 91.9 43.6 2.82 3039 92.7 43657 10873 1.222
Winchester Supreme 780 91.8 45.9 2.97 3005 92.7 44051 10442 1.222
Hodgdon Hybrid 100V 89.7 41.1 2.67 3024 99.1 43647 10062 1.223
Hodgdon H4350 88.8 41.2 2.67 2981 94.0 43766 10106 1.223
Accurate 4350 88.8 42.1 2.73 3102 98.3 46571 10908 1.223
Ramshot Hunter 88.1 43.1 2.79 3062 96.0 44179 10907 1.222
Vihtavuori N150 87.8 39.3 2.54 2994 99.9 45304 9483 1.222
Norma URP 87.4 40.9 2.65 3051 97.7 44128 10658 1.223
Norma 204 87.3 42.7 2.77 3018 92.4 43774 10594 1.222
IMR 4350 87.2 41.1 2.66 2981 94.1 43758 10096 1.223
Vihtavuori N550 85.1 41.2 2.67 3059 97.7 44744 10757 1.223
Vihtavuori N135 84.3 36.2 2.35 2987 100.0 45965 8769 1.223
Hodgdon H414 83.2 41.7 2.70 3060 95.1 44529 10872 1.222
Winchester 760 83.2 41.7 2.70 3060 95.1 44529 10872 1.222
Accurate 2700 83.1 41.1 2.66 2952 94.6 45367 9594 1.223
IMR 4007 SSC 82.7 39.7 2.57 2991 94.6 45057 10100 1.222
Alliant Reloder-17 82.7 41.1 2.66 3077 99.1 42286 10964 1.223
Norma 203 old 82.1 39.3 2.55 3061 99.7 46452 10209 1.223
IMR 4064 81.5 36.5 2.36 2979 98.5 44146 9643 1.222
Hodgdon H380 81.1 39.3 2.54 3031 97.6 45388 10302 1.222
Hodgdon VARGET 80.6 37.0 2.40 2972 98.2 43625 9708 1.223
Jaxdialation
Well-Known Member
My 243AI with 7.5 twist barrel prefers H4350. Load development worked this way:
Pressure test in .5 gr increments.
Once the max load is found, drop down 1.5 gr
from there work up in .2 gr increments
Pressure test in .5 gr increments.
Once the max load is found, drop down 1.5 gr
from there work up in .2 gr increments
westcliffe01
Well-Known Member
Jeebes, why did you choose the same twist rate as most factory rifles ? Most people who build customs go with a 1:8 so that they can shoot the 95Gr + bullets from Berger, Sierra etc. A 1:9 barrel is definitely limiting your choices of bullets. I see you are planning 85's for that the twist will be fine, but you could go with higher BC's if it had a faster twist,
It's not a real custom rifle. I took a 700 with the 22 inch barrel that was drilled and tapped and put a 24 inch take off sporter on it and my gunsmith has ai reamer and he changed the chamber for me for nothing. I don't really plan on reaching out further than 4-500 yards with it, I have other rifles for that.
westcliffe01
Well-Known Member
OK, good to hear you did not have a large investment into it. I don't get to hunt much past 350 yards, but the 95gr Bergers did reduce wind drift substantially even at 320 yards.
