Load Specifications
Load data in caliber 8 x 57 IRS with .323 | 150gr | Speer Hot-Cor bullet and 42 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are ReloadSwiss RS 60, IMR 3031 and Hodgdon BL-C2.
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>> | 86% | 42,511 psi | 89% | 2717 fps | 99.9% |
| Accurate 2460 | <<locked>> | 84% | 43,279 psi | 90% | 2756 fps | 98.6% |
| Accurate 2495 | <<locked>> | 92% | 41,060 psi | 86% | 2749 fps | 99.9% |
| Accurate 2520 | <<locked>> | 88% | 42,134 psi | 88% | 2785 fps | 98.1% |
| Accurate 4064 | <<locked>> | 94% | 40,988 psi | 86% | 2772 fps | 98.8% |
| ADI Benchmark 8208 | <<locked>> | 86% | 41,350 psi | 86% | 2720 fps | 96.1% |
| Alliant AR-Comp | <<locked>> | 88% | 42,032 psi | 88% | 2792 fps | 100% |
| Alliant Reloder-10x | <<locked>> | 82% | 42,656 psi | 89% | 2733 fps | 100% |
| Bofors RP3 | <<locked>> | 96% | 43,062 psi | 90% | 2818 fps | 96.4% |
| Hodgdon Benchmark | <<locked>> | 84% | 41,191 psi | 86% | 2674 fps | 96.7% |
| Hodgdon BL-C2 | <<locked>> | 88% | 41,582 psi | 87% | 2782 fps | 96.9% |
| Hodgdon H322 | <<locked>> | 84% | 40,901 psi | 85% | 2736 fps | 99.1% |
| Hodgdon LEVERevolution | <<locked>> | 94% | 42,496 psi | 89% | 2825 fps | 96.1% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 33,620 psi | 70% | 1785 fps | 100% |
| IMR 3031 | <<locked>> | 92% | 41,394 psi | 86% | 2805 fps | 99.7% |
| IMR 8208 XBR | <<locked>> | 86% | 41,350 psi | 86% | 2720 fps | 96.1% |
| Lovex D073.5 | <<locked>> | 84% | 43,207 psi | 90% | 2756 fps | 97.6% |
| Lovex D073.6 | <<locked>> | 90% | 42,134 psi | 88% | 2785 fps | 98.1% |
| Lovex S062 | <<locked>> | 92% | 41,249 psi | 86% | 2736 fps | 96.2% |
| Norma 201 | <<locked>> | 90% | 43,163 psi | 90% | 2759 fps | 96.7% |
| Norma 202 | <<locked>> | 90% | 43,178 psi | 90% | 2779 fps | 98.8% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 33,823 psi | 71% | 1827 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 82% | 40,915 psi | 85% | 2713 fps | 97.4% |
| ReloadSwiss RS 60 | <<locked>> | 96% | 41,437 psi | 87% | 2848 fps | 97.3% |
| Rottweil R 901 | <<locked>> | 86% | 42,090 psi | 88% | 2723 fps | 98.4% |
| Rottweil R 902 | <<locked>> | 90% | 40,901 psi | 85% | 2703 fps | 96.1% |
| Rottweil R 903 | <<locked>> | 98% | 42,670 psi | 89% | 2802 fps | 95.9% |
| Shooters World Match Rifle | <<locked>> | 90% | 42,134 psi | 88% | 2785 fps | 98.1% |
| Shooters World Precision | <<locked>> | 92% | 41,249 psi | 86% | 2736 fps | 96.2% |
| SNPE Vectan SP 3 | <<locked>> | 82% | 43,279 psi | 90% | 2746 fps | 99.8% |
| SNPE Vectan Tubal 3000 | <<locked>> | 88% | 42,946 psi | 90% | 2687 fps | 98.7% |
| SNPE Vectan Tubal 5000 | <<locked>> | 94% | 41,989 psi | 88% | 2684 fps | 99.3% |
| Somchem S321 | <<locked>> | 84% | 41,582 psi | 87% | 2749 fps | 96.5% |
| Somchem S335 | <<locked>> | 88% | 41,959 psi | 88% | 2687 fps | 99.1% |
| Vihtavuori N130 | <<locked>> | 84% | 43,149 psi | 90% | 2687 fps | 100% |
| Vihtavuori N133 | <<locked>> | 88% | 42,699 psi | 89% | 2694 fps | 99.9% |
| Vihtavuori N135 | <<locked>> | 92% | 41,684 psi | 87% | 2753 fps | 99.9% |
| Vihtavuori N140 | <<locked>> | 90% | 40,886 psi | 85% | 2713 fps | 98.7% |
| Vihtavuori N150 | <<locked>> | 98% | 42,322 psi | 88% | 2749 fps | 97% |
| Vihtavuori N530 | <<locked>> | 86% | 41,292 psi | 86% | 2713 fps | 96.2% |
| Vihtavuori N540 | <<locked>> | 92% | 42,047 psi | 88% | 2749 fps | 98.5% |
| Winchester 748 | <<locked>> | 86% | 43,163 psi | 90% | 2818 fps | 97.6% |
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% | 35,027 psi | 73% | 2562 fps | 99.1% |
| Accurate 2460 | <<locked>> | 80% | 37,956 psi | 79% | 2648 fps | 97.5% |
| Accurate 2495 | <<locked>> | 80% | 27,572 psi | 58% | 2434 fps | 97.4% |
| Accurate 2520 | <<locked>> | 82% | 34,084 psi | 71% | 2608 fps | 95.8% |
| Accurate 4064 | <<locked>> | 84% | 29,733 psi | 62% | 2507 fps | 95.5% |
| ADI Benchmark 8208 | <<locked>> | 84% | 38,899 psi | 81% | 2667 fps | 95.3% |
| Alliant AR-Comp | <<locked>> | 80% | 32,198 psi | 67% | 2582 fps | 99.9% |
| Alliant Reloder-10x | <<locked>> | 80% | 40,030 psi | 84% | 2680 fps | 100% |
| Bofors RP3 | <<locked>> | 94% | 40,321 psi | 84% | 2762 fps | 95.6% |
| Hodgdon Benchmark | <<locked>> | 80% | 36,448 psi | 76% | 2569 fps | 95.2% |
| Hodgdon BL-C2 | 50.4 gr | 84% | 36,260 psi | 76% | 2664 fps | 95.2% |
| Hodgdon H322 | <<locked>> | 80% | 35,897 psi | 75% | 2625 fps | 98.1% |
| Hodgdon LEVERevolution | <<locked>> | 92% | 39,943 psi | 83% | 2769 fps | 95.2% |
| Hodgdon TrailBoss | <<locked>> | 80% | 24,874 psi | 52% | 1594 fps | 100% |
| IMR 3031 | 42.2 gr | 80% | 28,384 psi | 59% | 2484 fps | 96.4% |
| IMR 8208 XBR | <<locked>> | 84% | 38,899 psi | 81% | 2667 fps | 95.3% |
| Lovex D073.5 | <<locked>> | 80% | 37,623 psi | 79% | 2641 fps | 96.1% |
| Lovex D073.6 | <<locked>> | 82% | 31,937 psi | 67% | 2556 fps | 95% |
| Lovex S062 | <<locked>> | 90% | 38,740 psi | 81% | 2680 fps | 95.5% |
| Norma 201 | <<locked>> | 86% | 38,116 psi | 80% | 2651 fps | 95.2% |
| Norma 202 | <<locked>> | 80% | 31,473 psi | 66% | 2516 fps | 95.6% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 24,947 psi | 52% | 1634 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 38,435 psi | 80% | 2661 fps | 96.8% |
| ReloadSwiss RS 60 | 54.4 gr | 92% | 36,274 psi | 76% | 2717 fps | 95.2% |
| Rottweil R 901 | <<locked>> | 80% | 35,012 psi | 73% | 2566 fps | 96.6% |
| Rottweil R 902 | <<locked>> | 88% | 38,464 psi | 80% | 2651 fps | 95.3% |
| Rottweil R 903 | <<locked>> | 96% | 39,972 psi | 84% | 2746 fps | 95.1% |
| Shooters World Match Rifle | <<locked>> | 82% | 31,937 psi | 67% | 2556 fps | 95% |
| Shooters World Precision | <<locked>> | 90% | 38,740 psi | 81% | 2680 fps | 95.5% |
| SNPE Vectan SP 3 | <<locked>> | 80% | 40,538 psi | 85% | 2690 fps | 99.5% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 33,446 psi | 70% | 2484 fps | 96.3% |
| SNPE Vectan Tubal 5000 | <<locked>> | 82% | 28,863 psi | 60% | 2385 fps | 95.8% |
| Somchem S321 | <<locked>> | 82% | 38,682 psi | 81% | 2687 fps | 95.7% |
| Somchem S335 | <<locked>> | 80% | 32,851 psi | 69% | 2487 fps | 97.1% |
| Vihtavuori N130 | <<locked>> | 80% | 38,029 psi | 79% | 2589 fps | 99.8% |
| Vihtavuori N133 | <<locked>> | 80% | 33,286 psi | 70% | 2497 fps | 98.7% |
| Vihtavuori N135 | <<locked>> | 80% | 28,297 psi | 59% | 2448 fps | 97.5% |
| Vihtavuori N140 | <<locked>> | 80% | 29,617 psi | 62% | 2448 fps | 95.3% |
| Vihtavuori N150 | <<locked>> | 94% | 37,188 psi | 78% | 2644 fps | 95.5% |
| Vihtavuori N530 | <<locked>> | 84% | 38,740 psi | 81% | 2661 fps | 95.4% |
| Vihtavuori N540 | <<locked>> | 84% | 32,460 psi | 68% | 2536 fps | 95.8% |
| Winchester 748 | <<locked>> | 80% | 35,012 psi | 73% | 2638 fps | 95% |
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 75 powders for 8 x 57 IRS loaded with the .323 | 150gr | Speer Hot-Cor. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 2,861 fps; across all powders the maximum-charge window runs from 1,785 fps to 2,861 fps. Hodgdon Hybrid 100V gives the best case fill at 100 %, and 75 of the 75 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 150.0 gr projectile in 0.323" calls for a 1:6.0 twist; slower twists will usually not stabilise this weight. Hodgdon Hybrid 100V, Hodgdon TrailBoss, Lovex S065 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. ReloadSwiss RS 60, IMR 3031, Hodgdon BL-C2 rank at the top here: for 8 x 57 IRS with the .323 | 150gr | Speer Hot-Cor they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, ADI AR 2206H, ADI AR 2208, Alliant Power Pro 2000-MR 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.