Load Specifications
Load data in caliber 8 x 57 IRS with .323 | 120gr | Impala LWHV LS bullet and 27 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Alliant AR-Comp, IMR 3031 and Accurate 2495.
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.
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Max Load - Barrel Length: 23.62"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2015 | <<locked>> | 88% | 41,017 psi | 86% | 2949 fps | 98.5% |
| Accurate 2460 | <<locked>> | 86% | 42,076 psi | 88% | 2986 fps | 95.9% |
| Accurate 2495 | <<locked>> | 96% | 42,148 psi | 88% | 3038 fps | 99% |
| Accurate 4064 | <<locked>> | 98% | 41,727 psi | 87% | 3045 fps | 96.7% |
| Accurate LT-30 | <<locked>> | 82% | 42,699 psi | 89% | 2904 fps | 97.6% |
| ADI AR 2219 | <<locked>> | 82% | 40,582 psi | 85% | 2986 fps | 96.9% |
| Alliant AR-Comp | <<locked>> | 92% | 42,424 psi | 89% | 3081 fps | 100% |
| Alliant Reloder-10x | <<locked>> | 84% | 41,423 psi | 87% | 2982 fps | 99.3% |
| Baschieri & Pellagri 106 | <<locked>> | 82% | 41,133 psi | 86% | 2884 fps | 97.6% |
| Hodgdon H322 | <<locked>> | 86% | 42,206 psi | 88% | 3025 fps | 97.3% |
| Hodgdon H335 | <<locked>> | 86% | 43,062 psi | 90% | 3038 fps | 96.5% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 33,388 psi | 70% | 1978 fps | 100% |
| IMR 3031 | <<locked>> | 94% | 42,931 psi | 90% | 3107 fps | 98.3% |
| IMR 4198 | <<locked>> | 84% | 42,250 psi | 88% | 2963 fps | 99.8% |
| Norma 202 | <<locked>> | 92% | 41,350 psi | 86% | 2999 fps | 96% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 33,330 psi | 70% | 2021 fps | 100% |
| Rottweil R 901 | <<locked>> | 88% | 41,452 psi | 87% | 2956 fps | 95.7% |
| SNPE Vectan SP 10 | <<locked>> | 82% | 41,423 psi | 87% | 2992 fps | 95.9% |
| SNPE Vectan SP 3 | <<locked>> | 84% | 41,568 psi | 87% | 2979 fps | 98% |
| SNPE Vectan Tubal 3000 | <<locked>> | 90% | 41,771 psi | 87% | 2910 fps | 96% |
| SNPE Vectan Tubal 5000 | <<locked>> | 98% | 42,598 psi | 89% | 2946 fps | 97.4% |
| Somchem S335 | <<locked>> | 92% | 43,250 psi | 90% | 2966 fps | 97.4% |
| Vihtavuori N130 | <<locked>> | 86% | 41,727 psi | 87% | 2927 fps | 99.2% |
| Vihtavuori N133 | <<locked>> | 90% | 41,089 psi | 86% | 2923 fps | 98.4% |
| Vihtavuori N135 | <<locked>> | 96% | 42,076 psi | 88% | 3035 fps | 98.9% |
| Vihtavuori N140 | <<locked>> | 94% | 41,452 psi | 87% | 2976 fps | 96.5% |
| Vihtavuori N540 | <<locked>> | 96% | 42,786 psi | 89% | 3015 fps | 96.2% |
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% | 32,474 psi | 68% | 2736 fps | 96.1% |
| Accurate 2460 | <<locked>> | 84% | 39,479 psi | 82% | 2927 fps | 95.1% |
| Accurate 2495 | 46.2 gr | 84% | 29,254 psi | 61% | 2713 fps | 95.3% |
| Accurate 4064 | <<locked>> | 94% | 37,086 psi | 77% | 2940 fps | 95.3% |
| Accurate LT-30 | <<locked>> | 80% | 40,277 psi | 84% | 2851 fps | 97% |
| ADI AR 2219 | <<locked>> | 80% | 38,203 psi | 80% | 2930 fps | 96.2% |
| Alliant AR-Comp | 43.5 gr | 80% | 29,559 psi | 62% | 2743 fps | 97.6% |
| Alliant Reloder-10x | <<locked>> | 80% | 36,898 psi | 77% | 2877 fps | 98.5% |
| Baschieri & Pellagri 106 | <<locked>> | 80% | 38,711 psi | 81% | 2828 fps | 96.9% |
| Hodgdon H322 | <<locked>> | 80% | 35,056 psi | 73% | 2848 fps | 95% |
| Hodgdon H335 | <<locked>> | 84% | 40,422 psi | 84% | 2979 fps | 95.7% |
| Hodgdon TrailBoss | <<locked>> | 80% | 24,860 psi | 52% | 1772 fps | 100% |
| IMR 3031 | 46.7 gr | 86% | 33,794 psi | 71% | 2874 fps | 95.5% |
| IMR 4198 | <<locked>> | 80% | 37,826 psi | 79% | 2861 fps | 99.3% |
| Norma 202 | <<locked>> | 90% | 38,928 psi | 81% | 2943 fps | 95.3% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 24,932 psi | 52% | 1814 fps | 100% |
| Rottweil R 901 | <<locked>> | 86% | 39,320 psi | 82% | 2907 fps | 95% |
| SNPE Vectan SP 10 | <<locked>> | 80% | 38,827 psi | 81% | 2933 fps | 95% |
| SNPE Vectan SP 3 | <<locked>> | 80% | 36,912 psi | 77% | 2867 fps | 96.7% |
| SNPE Vectan Tubal 3000 | <<locked>> | 88% | 39,378 psi | 82% | 2858 fps | 95.3% |
| SNPE Vectan Tubal 5000 | <<locked>> | 92% | 35,824 psi | 75% | 2792 fps | 95.4% |
| Somchem S335 | <<locked>> | 86% | 36,477 psi | 76% | 2808 fps | 95.4% |
| Vihtavuori N130 | <<locked>> | 80% | 35,331 psi | 74% | 2776 fps | 97.9% |
| Vihtavuori N133 | <<locked>> | 80% | 30,821 psi | 64% | 2664 fps | 95.3% |
| Vihtavuori N135 | <<locked>> | 84% | 29,544 psi | 62% | 2710 fps | 95.1% |
| Vihtavuori N140 | <<locked>> | 90% | 36,912 psi | 77% | 2867 fps | 95% |
| Vihtavuori N540 | <<locked>> | 94% | 40,147 psi | 84% | 2956 fps | 95.4% |
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 59 powders for 8 x 57 IRS loaded with the .323 | 120gr | Impala LWHV LS. IMR 3031 delivers the highest muzzle velocity at 3,107 fps; across all powders the maximum-charge window runs from 1,978 fps to 3,107 fps. Hodgdon TrailBoss gives the best case fill at 100 %, and 59 of the 59 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (330 MPa), the top charges use 70–90 %, leaving at least 10 % headroom. The 120.0 gr projectile in 0.323" calls for a 1:14.0 twist; slower twists will usually not stabilise this weight. Hodgdon TrailBoss, ReloadSwiss RS 14, ReloadSwiss RS 60 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 AR-Comp, IMR 3031, Accurate 2495 rank at the top here: for 8 x 57 IRS with the .323 | 120gr | Impala LWHV LS they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, ADI AR 2206H, ADI Benchmark 8208, Alliant Power Pro 1200-R 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.