Load Specifications
Load data in caliber 8 x 64 S with .323 | 139gr | Geco ZERO bullet and 78 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Alliant Power Pro 1200-R, Winchester 748 and IMR 3031.
Important Notice: DO NOT go below Minimum Charge or above Maximum Charge. Since we have no control over the equipment and components used, any responsibility and liability for the results achieved is rejected.
Only powders/loads that match the current filter criteria are displayed: max pressure of a load ≤ 90% of max. standardized pressure, fill rate ≥ 80% and propellant combustion ≥ 95%. Use the sliders above the tables to adjust these thresholds.
Charge: Powder weight in grains. Start with the minimum load and work up carefully.
FR (Fill Rate): Case fill as a percentage. Values above 100% mean compressed loads.
MaxP / %: Maximum chamber pressure in bar and as a percentage of the standardized maximum for this caliber.
V(0): Muzzle velocity in feet per second (fps) at the standardized barrel length.
z (Powder Burn): Estimated propellant combustion percentage at bullet exit.
A valid access license is required to use the Personalized Load Calculator.
You can find more information in our FAQ: How can I use the Personalized Load Calculator?
Max Load - Barrel Length: 23.62"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2015 | <<locked>> | 94% | 52,997 psi | 90% | 3022 fps | 100% |
| Accurate 2230 | <<locked>> | 84% | 51,184 psi | 87% | 3051 fps | 96.1% |
| Accurate 2460 | <<locked>> | 90% | 51,547 psi | 88% | 3031 fps | 99.5% |
| Accurate 2495ᴾ | <<locked>> | 100% | 51,851 psi | 88% | 3061 fps | 100% |
| Accurate 2520 | <<locked>> | 94% | 52,750 psi | 90% | 3087 fps | 99.4% |
| Accurate 4064ᴾ | <<locked>> | 100% | 48,066 psi | 82% | 3031 fps | 99.5% |
| Accurate LT-30 | <<locked>> | 86% | 51,430 psi | 88% | 2933 fps | 99.9% |
| Accurate LT-32 | <<locked>> | 86% | 51,837 psi | 88% | 2949 fps | 99.2% |
| ADI AR 2206H | <<locked>> | 96% | 52,199 psi | 89% | 3077 fps | 96.9% |
| ADI AR 2207 | <<locked>> | 84% | 52,141 psi | 89% | 2969 fps | 100% |
| ADI AR 2219 | <<locked>> | 86% | 50,676 psi | 86% | 3041 fps | 99.9% |
| ADI Benchmark 8208 | <<locked>> | 94% | 51,866 psi | 88% | 3045 fps | 98% |
| Alliant AR-Comp | <<locked>> | 94% | 50,024 psi | 85% | 3054 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 90% | 52,605 psi | 90% | 3153 fps | 97.6% |
| Alliant Reloder- TS 15.5ᴾ | <<locked>> | 100% | 48,167 psi | 82% | 3025 fps | 97% |
| Alliant Reloder-10x | <<locked>> | 88% | 50,096 psi | 85% | 2995 fps | 100% |
| Alliant Reloder-15ᴾ | <<locked>> | 100% | 52,692 psi | 90% | 3107 fps | 96.5% |
| Alliant Reloder-7 | <<locked>> | 82% | 50,154 psi | 85% | 2936 fps | 100% |
| Baschieri & Pellagri 106 | <<locked>> | 86% | 50,227 psi | 86% | 2920 fps | 99.9% |
| Bofors RP3ᴾ | <<locked>> | 100% | 47,805 psi | 81% | 3031 fps | 97.1% |
| Hodgdon Benchmark | <<locked>> | 92% | 51,445 psi | 88% | 2992 fps | 98.4% |
| Hodgdon BL-C2 | <<locked>> | 94% | 50,009 psi | 85% | 3064 fps | 98.3% |
| Hodgdon CFE223 | <<locked>> | 92% | 51,924 psi | 88% | 3153 fps | 96.2% |
| Hodgdon H322 | <<locked>> | 90% | 52,678 psi | 90% | 3077 fps | 99.9% |
| Hodgdon H335 | <<locked>> | 88% | 50,212 psi | 85% | 3035 fps | 99.5% |
| Hodgdon H4198 | <<locked>> | 82% | 50,111 psi | 85% | 2930 fps | 99.7% |
| Hodgdon H4895 | <<locked>> | 96% | 52,562 psi | 89% | 3094 fps | 97.6% |
| Hodgdon LEVERevolution | <<locked>> | 98% | 50,778 psi | 86% | 3110 fps | 97.7% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 33,185 psi | 56% | 1877 fps | 100% |
| Hodgdon VARGET | <<locked>> | 96% | 51,053 psi | 87% | 3045 fps | 97.2% |
| IMR 3031 | <<locked>> | 96% | 50,734 psi | 86% | 3100 fps | 100% |
| IMR 4064ᴾ | <<locked>> | 100% | 52,576 psi | 90% | 3051 fps | 96.4% |
| IMR 4198 | <<locked>> | 88% | 51,126 psi | 87% | 2969 fps | 100% |
| IMR 4895 | <<locked>> | 98% | 50,575 psi | 86% | 3087 fps | 96.7% |
| IMR 8208 XBR | <<locked>> | 94% | 51,866 psi | 88% | 3045 fps | 98% |
| Lovex D073.4 | <<locked>> | 84% | 51,634 psi | 88% | 3045 fps | 99.1% |
| Lovex D073.5 | <<locked>> | 90% | 51,488 psi | 88% | 3031 fps | 98.7% |
| Lovex D073.6 | <<locked>> | 96% | 50,053 psi | 85% | 3054 fps | 99.1% |
| Lovex S060 | <<locked>> | 94% | 50,270 psi | 86% | 2966 fps | 96.5% |
| Lovex S062ᴾ | <<locked>> | 100% | 51,517 psi | 88% | 3051 fps | 98.1% |
| Norma 200 | <<locked>> | 86% | 52,982 psi | 90% | 3015 fps | 100% |
| Norma 201 | <<locked>> | 96% | 50,850 psi | 87% | 3028 fps | 97.9% |
| Norma 202 | <<locked>> | 96% | 51,039 psi | 87% | 3048 fps | 99.6% |
| Norma 203Bᴾ | <<locked>> | 100% | 51,692 psi | 88% | 3091 fps | 96.8% |
| Ramshot Big Gameᴾ | <<locked>> | 100% | 52,605 psi | 90% | 3120 fps | 96.7% |
| Ramshot Wild Boar | <<locked>> | 94% | 51,503 psi | 88% | 3071 fps | 96.7% |
| Ramshot X-Terminator | <<locked>> | 90% | 50,328 psi | 86% | 2989 fps | 96.3% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 33,243 psi | 57% | 1919 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 90% | 51,953 psi | 88% | 3045 fps | 99.1% |
| ReloadSwiss RS 52 | <<locked>> | 98% | 52,054 psi | 89% | 3169 fps | 96.2% |
| ReloadSwiss RS 60ᴾ | <<locked>> | 100% | 46,050 psi | 78% | 3071 fps | 98.1% |
| Rottweil R 901 | <<locked>> | 94% | 51,532 psi | 88% | 3028 fps | 99.4% |
| Rottweil R 902 | <<locked>> | 98% | 50,908 psi | 87% | 3018 fps | 97.9% |
| Rottweil R 903ᴾ | <<locked>> | 100% | 44,237 psi | 75% | 2953 fps | 95.8% |
| Shooters World AR Plus | <<locked>> | 84% | 51,634 psi | 88% | 3045 fps | 99.1% |
| Shooters World Match Rifle | <<locked>> | 96% | 50,053 psi | 85% | 3054 fps | 99.1% |
| Shooters World Precisionᴾ | <<locked>> | 100% | 51,517 psi | 88% | 3051 fps | 98.1% |
| Shooters World Tactical Rifle | <<locked>> | 88% | 52,460 psi | 89% | 3012 fps | 97.7% |
| SNPE Vectan BA6 1/2 | <<locked>> | 84% | 52,431 psi | 89% | 2713 fps | 100% |
| SNPE Vectan SP 10 | <<locked>> | 86% | 51,010 psi | 87% | 3045 fps | 99.5% |
| SNPE Vectan SP 3 | <<locked>> | 88% | 51,169 psi | 87% | 3015 fps | 100% |
| SNPE Vectan SP 9 | <<locked>> | 96% | 50,821 psi | 87% | 3048 fps | 96.6% |
| SNPE Vectan Tubal 3000 | <<locked>> | 94% | 50,647 psi | 86% | 2949 fps | 99.4% |
| SNPE Vectan Tubal 5000ᴾ | <<locked>> | 100% | 49,443 psi | 84% | 2936 fps | 99.8% |
| Somchem S321 | <<locked>> | 92% | 53,156 psi | 90% | 3084 fps | 98.5% |
| Somchem S335 | <<locked>> | 96% | 52,460 psi | 89% | 2995 fps | 99.9% |
| Somchem S341 | <<locked>> | 94% | 49,748 psi | 85% | 3009 fps | 96.2% |
| Somchem S355ᴾ | <<locked>> | 100% | 45,716 psi | 78% | 2966 fps | 96% |
| Vihtavuori N120 | <<locked>> | 84% | 52,170 psi | 89% | 2920 fps | 100% |
| Vihtavuori N130 | <<locked>> | 90% | 50,430 psi | 86% | 2940 fps | 100% |
| Vihtavuori N133 | <<locked>> | 94% | 50,256 psi | 86% | 2949 fps | 100% |
| Vihtavuori N135ᴾ | <<locked>> | 100% | 52,344 psi | 89% | 3061 fps | 100% |
| Vihtavuori N140 | <<locked>> | 98% | 51,663 psi | 88% | 3028 fps | 99.7% |
| Vihtavuori N150ᴾ | <<locked>> | 100% | 43,990 psi | 75% | 2904 fps | 97% |
| Vihtavuori N530 | <<locked>> | 94% | 52,475 psi | 89% | 3048 fps | 98.2% |
| Vihtavuori N540 | <<locked>> | 98% | 49,922 psi | 85% | 3015 fps | 99.4% |
| Winchester 748 | <<locked>> | 94% | 50,792 psi | 86% | 3087 fps | 98.7% |
| Winchester StaBALL Match | <<locked>> | 96% | 49,951 psi | 85% | 3048 fps | 97% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 23.62"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2015 | <<locked>> | 80% | 33,736 psi | 57% | 2654 fps | 98.5% |
| Accurate 2230 | <<locked>> | 82% | 47,543 psi | 81% | 2986 fps | 95.2% |
| Accurate 2460 | <<locked>> | 80% | 36,274 psi | 62% | 2733 fps | 96.6% |
| Accurate 2495 | <<locked>> | 80% | 25,773 psi | 44% | 2493 fps | 96% |
| Accurate 2520 | <<locked>> | 82% | 34,229 psi | 58% | 2717 fps | 95.4% |
| Accurate 4064 | <<locked>> | 86% | 30,023 psi | 51% | 2631 fps | 95.1% |
| Accurate LT-30 | <<locked>> | 80% | 42,772 psi | 73% | 2779 fps | 99.2% |
| Accurate LT-32 | <<locked>> | 80% | 43,134 psi | 73% | 2789 fps | 97.9% |
| ADI AR 2206H | <<locked>> | 92% | 45,876 psi | 78% | 2963 fps | 95.4% |
| ADI AR 2207 | <<locked>> | 80% | 45,788 psi | 78% | 2871 fps | 100% |
| ADI AR 2219 | <<locked>> | 80% | 41,089 psi | 70% | 2864 fps | 98.8% |
| ADI Benchmark 8208 | <<locked>> | 86% | 40,074 psi | 68% | 2815 fps | 95.2% |
| Alliant AR-Comp | <<locked>> | 80% | 30,995 psi | 53% | 2671 fps | 99.7% |
| Alliant Power Pro 1200-R | 50.1 gr | 84% | 42,888 psi | 73% | 2963 fps | 95.3% |
| Alliant Reloder- TS 15.5 | <<locked>> | 96% | 42,322 psi | 72% | 2913 fps | 95.6% |
| Alliant Reloder-10x | <<locked>> | 80% | 38,856 psi | 66% | 2785 fps | 99.9% |
| Alliant Reloder-15 | <<locked>> | 98% | 49,371 psi | 84% | 3048 fps | 95.7% |
| Alliant Reloder-7 | <<locked>> | 80% | 46,963 psi | 80% | 2884 fps | 100% |
| Baschieri & Pellagri 106 | <<locked>> | 80% | 41,379 psi | 70% | 2759 fps | 99.2% |
| Bofors RP3 | <<locked>> | 96% | 41,582 psi | 71% | 2910 fps | 95.5% |
| Hodgdon Benchmark | <<locked>> | 82% | 37,652 psi | 64% | 2717 fps | 95.1% |
| Hodgdon BL-C2 | <<locked>> | 86% | 37,666 psi | 64% | 2815 fps | 95.2% |
| Hodgdon CFE223 | <<locked>> | 90% | 48,385 psi | 82% | 3091 fps | 95.3% |
| Hodgdon H322 | <<locked>> | 80% | 37,449 psi | 64% | 2785 fps | 98.1% |
| Hodgdon H335 | <<locked>> | 80% | 37,956 psi | 65% | 2792 fps | 97.3% |
| Hodgdon H4198 | <<locked>> | 80% | 47,166 psi | 80% | 2877 fps | 99.4% |
| Hodgdon H4895 | <<locked>> | 90% | 43,221 psi | 74% | 2917 fps | 95.4% |
| Hodgdon LEVERevolution | <<locked>> | 92% | 41,597 psi | 71% | 2927 fps | 95.3% |
| Hodgdon TrailBoss | <<locked>> | 80% | 24,468 psi | 42% | 1677 fps | 100% |
| Hodgdon VARGET | <<locked>> | 92% | 44,802 psi | 76% | 2927 fps | 95.7% |
| IMR 3031 | 46.1 gr | 80% | 29,515 psi | 50% | 2635 fps | 96.3% |
| IMR 4064 | <<locked>> | 98% | 49,458 psi | 84% | 2995 fps | 95.7% |
| IMR 4198 | <<locked>> | 80% | 40,103 psi | 68% | 2772 fps | 100% |
| IMR 4895 | <<locked>> | 94% | 44,266 psi | 75% | 2966 fps | 95.1% |
| IMR 8208 XBR | <<locked>> | 86% | 40,074 psi | 68% | 2815 fps | 95.2% |
| Lovex D073.4 | <<locked>> | 80% | 44,773 psi | 76% | 2920 fps | 98% |
| Lovex D073.5 | <<locked>> | 80% | 36,085 psi | 61% | 2723 fps | 95% |
| Lovex D073.6 | <<locked>> | 86% | 35,288 psi | 60% | 2756 fps | 95.7% |
| Lovex S060 | <<locked>> | 90% | 44,512 psi | 76% | 2858 fps | 95% |
| Lovex S062 | <<locked>> | 92% | 39,769 psi | 68% | 2825 fps | 95.3% |
| Norma 200 | <<locked>> | 80% | 43,642 psi | 74% | 2861 fps | 100% |
| Norma 201 | <<locked>> | 88% | 39,262 psi | 67% | 2799 fps | 95.1% |
| Norma 202 | <<locked>> | 82% | 32,126 psi | 55% | 2648 fps | 95.3% |
| Norma 203B | <<locked>> | 96% | 45,339 psi | 77% | 2976 fps | 95.3% |
| Ramshot Big Game | <<locked>> | 96% | 45,701 psi | 78% | 2989 fps | 95% |
| Ramshot Wild Boar | <<locked>> | 90% | 44,788 psi | 76% | 2943 fps | 95% |
| Ramshot X-Terminator | <<locked>> | 88% | 47,253 psi | 80% | 2933 fps | 95.5% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 24,439 psi | 42% | 1716 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 37,246 psi | 63% | 2753 fps | 95.9% |
| ReloadSwiss RS 52 | <<locked>> | 96% | 48,617 psi | 83% | 3104 fps | 95.4% |
| ReloadSwiss RS 60 | <<locked>> | 94% | 37,753 psi | 64% | 2871 fps | 95.3% |
| Rottweil R 901 | <<locked>> | 80% | 33,547 psi | 57% | 2648 fps | 95.6% |
| Rottweil R 902 | <<locked>> | 90% | 39,552 psi | 67% | 2795 fps | 95.1% |
| Rottweil R 903 | <<locked>> | 98% | 41,495 psi | 71% | 2897 fps | 95% |
| Shooters World AR Plus | <<locked>> | 80% | 44,773 psi | 76% | 2920 fps | 98% |
| Shooters World Match Rifle | <<locked>> | 86% | 35,288 psi | 60% | 2756 fps | 95.7% |
| Shooters World Precision | <<locked>> | 92% | 39,769 psi | 68% | 2825 fps | 95.3% |
| Shooters World Tactical Rifle | <<locked>> | 82% | 42,279 psi | 72% | 2822 fps | 95.4% |
| SNPE Vectan BA6 1/2 | <<locked>> | 80% | 47,268 psi | 80% | 2641 fps | 100% |
| SNPE Vectan SP 10 | <<locked>> | 80% | 41,553 psi | 71% | 2864 fps | 98.1% |
| SNPE Vectan SP 3 | <<locked>> | 80% | 39,566 psi | 67% | 2799 fps | 99.1% |
| SNPE Vectan SP 9 | <<locked>> | 94% | 47,384 psi | 81% | 2982 fps | 95.7% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 32,416 psi | 55% | 2572 fps | 95.4% |
| SNPE Vectan Tubal 5000 | <<locked>> | 84% | 29,602 psi | 50% | 2516 fps | 95.6% |
| Somchem S321 | <<locked>> | 84% | 40,335 psi | 69% | 2841 fps | 95.7% |
| Somchem S335 | <<locked>> | 80% | 31,589 psi | 54% | 2569 fps | 96.1% |
| Somchem S341 | <<locked>> | 92% | 46,325 psi | 79% | 2946 fps | 95.3% |
| Somchem S355 | <<locked>> | 98% | 42,786 psi | 73% | 2907 fps | 95.2% |
| Vihtavuori N120 | <<locked>> | 80% | 45,890 psi | 78% | 2825 fps | 100% |
| Vihtavuori N130 | <<locked>> | 80% | 36,999 psi | 63% | 2690 fps | 99.6% |
| Vihtavuori N133 | <<locked>> | 80% | 32,314 psi | 55% | 2589 fps | 98.1% |
| Vihtavuori N135 | <<locked>> | 80% | 27,122 psi | 46% | 2526 fps | 96.5% |
| Vihtavuori N140 | <<locked>> | 82% | 30,400 psi | 52% | 2582 fps | 95.1% |
| Vihtavuori N150 | <<locked>> | 96% | 38,566 psi | 66% | 2792 fps | 95.5% |
| Vihtavuori N530 | <<locked>> | 86% | 40,103 psi | 68% | 2812 fps | 95.3% |
| Vihtavuori N540 | <<locked>> | 86% | 33,518 psi | 57% | 2674 fps | 95.7% |
| Winchester 748 | 53.7 gr | 86% | 38,508 psi | 66% | 2841 fps | 95.8% |
| Winchester StaBALL Match | <<locked>> | 92% | 43,526 psi | 74% | 2927 fps | 95.5% |
Recommended = one of the top powders for this cartridge and bullet combination.
ᴾ possible press load - work up slowly to this load while watching for signs of excessive pressure.
This overview compares 91 powders for 8 x 64 S loaded with the .323 | 139gr | Geco ZERO. ReloadSwiss RS 52 delivers the highest muzzle velocity at 3,169 fps; across all powders the maximum-charge window runs from 1,877 fps to 3,169 fps. Accurate 2495 gives the best case fill at 100 %, and 91 of the 91 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (405 MPa), the top charges use 56–90 %, leaving at least 10 % headroom. The 139.0 gr projectile in 0.323" calls for a 1:14.5 twist; slower twists will usually not stabilise this weight. Accurate 2495, Accurate 4064, ADI AR 2208 reach 100 % fill or more at maximum charge, so these are compressed loads: they need a long drop tube to seat cleanly and react sensitively to the case capacity of your own brass lot. Alliant Power Pro 1200-R, Winchester 748, IMR 3031 rank at the top here: for 8 x 64 S with the .323 | 139gr | Geco ZERO they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, Alliant Reloder-17, Hodgdon H380, IMR 4166 Enduron burn incompletely and react more sensitively to barrel length and temperature. Always begin at the start load and work up in small increments while checking case and primer for pressure signs.