Load Specifications
Load data in caliber 8.5 mm Messner Mag. with .338 | 250gr | Woodleigh PP SN bullet and 81 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Alliant Reloder-26, Accurate MAGPRO and Ramshot Grand.
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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You can find more information in our FAQ: How can I use the Personalized Load Calculator?
Max Load - Barrel Length: 25.6"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2700 | <<locked>> | 84% | 57,667 psi | 90% | 2677 fps | 100% |
| Accurate 3100 | <<locked>> | 96% | 56,478 psi | 89% | 2694 fps | 100% |
| Accurate 4350 | <<locked>> | 86% | 54,578 psi | 86% | 2717 fps | 100% |
| Accurate MAGPRO | <<locked>> | 96% | 55,811 psi | 87% | 2838 fps | 98% |
| ADI AR 2208 | <<locked>> | 82% | 55,854 psi | 88% | 2635 fps | 100% |
| ADI AR 2209 | <<locked>> | 92% | 55,201 psi | 87% | 2728 fps | 99.5% |
| ADI AR 2213 | <<locked>> | 96% | 56,536 psi | 89% | 2787 fps | 99% |
| ADI AR 2217ᴾ | <<locked>> | 100% | 47,398 psi | 74% | 2631 fps | 97.7% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 42,670 psi | 67% | 2597 fps | 99.2% |
| Alliant Reloder- TS 15.5 | <<locked>> | 82% | 57,217 psi | 90% | 2657 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 88% | 55,347 psi | 87% | 2727 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 84% | 56,550 psi | 89% | 2741 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 92% | 54,621 psi | 86% | 2717 fps | 99.4% |
| Alliant Reloder-22 | <<locked>> | 96% | 56,391 psi | 88% | 2783 fps | 99.7% |
| Alliant Reloder-23 | <<locked>> | 98% | 57,334 psi | 90% | 2750 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 53,548 psi | 84% | 2757 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 92% | 53,795 psi | 84% | 2786 fps | 100% |
| Baschieri & Pellagri 109 | <<locked>> | 96% | 54,839 psi | 86% | 2694 fps | 96.1% |
| Bofors RP15 | <<locked>> | 98% | 55,317 psi | 87% | 2812 fps | 99.7% |
| Bofors RP30ᴾ | <<locked>> | 100% | 49,269 psi | 77% | 2699 fps | 98.4% |
| Bofors RP5 | <<locked>> | 96% | 56,391 psi | 88% | 2828 fps | 99.8% |
| Bofors RP7 | <<locked>> | 86% | 57,029 psi | 89% | 2674 fps | 99.9% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 48,443 psi | 76% | 2700 fps | 98.9% |
| Hodgdon H414 | <<locked>> | 84% | 57,276 psi | 90% | 2743 fps | 100% |
| Hodgdon H4350 | <<locked>> | 88% | 57,406 psi | 90% | 2756 fps | 99.9% |
| Hodgdon H4831 | <<locked>> | 98% | 55,709 psi | 87% | 2716 fps | 98.4% |
| Hodgdon H4831 SC | <<locked>> | 94% | 55,506 psi | 87% | 2713 fps | 98.3% |
| Hodgdon Hybrid 100V | <<locked>> | 90% | 55,622 psi | 87% | 2652 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 51,851 psi | 81% | 2867 fps | 100% |
| Hodgdon Superformance | <<locked>> | 86% | 56,492 psi | 89% | 2763 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,956 psi | 59% | 1656 fps | 100% |
| IMR 4064 | <<locked>> | 82% | 54,984 psi | 86% | 2648 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 84% | 56,826 psi | 89% | 2647 fps | 100% |
| IMR 4350 | <<locked>> | 88% | 55,027 psi | 86% | 2700 fps | 99.9% |
| IMR 4451 Enduron | <<locked>> | 84% | 55,216 psi | 87% | 2687 fps | 100% |
| IMR 4831 | <<locked>> | 92% | 55,956 psi | 88% | 2683 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 94% | 57,653 psi | 90% | 2756 fps | 99% |
| IMR 7828 SSC | <<locked>> | 94% | 54,418 psi | 85% | 2767 fps | 98.8% |
| Lovex S065 | <<locked>> | 86% | 55,695 psi | 87% | 2646 fps | 100% |
| Lovex S070 | <<locked>> | 88% | 57,246 psi | 90% | 2692 fps | 100% |
| Lovex S071ᴾ | <<locked>> | 100% | 54,085 psi | 85% | 2658 fps | 100% |
| Norma 204 | <<locked>> | 88% | 55,825 psi | 87% | 2714 fps | 99.4% |
| Norma 217ᴾ | <<locked>> | 100% | 37,840 psi | 59% | 2527 fps | 97.5% |
| Norma MRP | <<locked>> | 94% | 56,144 psi | 88% | 2804 fps | 100% |
| Norma URP | <<locked>> | 88% | 56,550 psi | 89% | 2708 fps | 100% |
| Ramshot Grand | <<locked>> | 92% | 54,143 psi | 85% | 2775 fps | 99.1% |
| Ramshot Hunter | <<locked>> | 88% | 55,274 psi | 87% | 2715 fps | 100% |
| Ramshot Magnum | <<locked>> | 96% | 55,042 psi | 86% | 2752 fps | 99.9% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 38,130 psi | 60% | 1696 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 82% | 56,057 psi | 88% | 2727 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 86% | 54,491 psi | 85% | 2699 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 88% | 56,391 psi | 88% | 2778 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 53,693 psi | 84% | 2821 fps | 100% |
| ReloadSwiss RS 80ᴾ | <<locked>> | 100% | 48,283 psi | 76% | 2705 fps | 96.6% |
| Rottweil R 903 | <<locked>> | 82% | 54,984 psi | 86% | 2627 fps | 100% |
| Rottweil R 904 | <<locked>> | 92% | 56,521 psi | 89% | 2700 fps | 99% |
| Rottweil R 905 | <<locked>> | 92% | 54,099 psi | 85% | 2707 fps | 99.5% |
| Rottweil R 907 | <<locked>> | 86% | 57,029 psi | 89% | 2674 fps | 99.9% |
| Shooters World Long Rifle | <<locked>> | 86% | 55,695 psi | 87% | 2646 fps | 100% |
| Shooters World SW4350 | <<locked>> | 88% | 57,246 psi | 90% | 2733 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 82% | 56,333 psi | 88% | 2681 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 82% | 55,013 psi | 86% | 2505 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 86% | 54,853 psi | 86% | 2603 fps | 99.9% |
| SNPE Vectan Tubal 8000 | <<locked>> | 94% | 57,334 psi | 90% | 2799 fps | 99.9% |
| Somchem S355 | <<locked>> | 82% | 54,708 psi | 86% | 2621 fps | 100% |
| Somchem S361 | <<locked>> | 90% | 54,360 psi | 85% | 2642 fps | 98.1% |
| Somchem S365 | <<locked>> | 90% | 56,797 psi | 89% | 2710 fps | 100% |
| Somchem S385 | <<locked>> | 92% | 54,592 psi | 86% | 2682 fps | 99.8% |
| Unknown powder | <<locked>> | 86% | 56,956 psi | 89% | 2712 fps | 100% |
| Vihtavuori N150 | <<locked>> | 88% | 56,449 psi | 88% | 2605 fps | 100% |
| Vihtavuori N160 | <<locked>> | 86% | 57,276 psi | 90% | 2682 fps | 100% |
| Vihtavuori N165 | <<locked>> | 98% | 55,912 psi | 88% | 2688 fps | 99.7% |
| Vihtavuori N550 | <<locked>> | 86% | 57,624 psi | 90% | 2724 fps | 100% |
| Vihtavuori N555 | <<locked>> | 94% | 56,188 psi | 88% | 2730 fps | 100% |
| Vihtavuori N560 | <<locked>> | 96% | 56,608 psi | 89% | 2811 fps | 98.8% |
| Vihtavuori N565ᴾ | <<locked>> | 100% | 57,000 psi | 89% | 2779 fps | 98.8% |
| Vihtavuori N568ᴾ | <<locked>> | 100% | 49,153 psi | 77% | 2714 fps | 96.3% |
| Winchester 6.5 StaBALL | <<locked>> | 86% | 54,056 psi | 85% | 2615 fps | 100% |
| Winchester 760 | <<locked>> | 84% | 57,276 psi | 90% | 2743 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 98% | 55,637 psi | 87% | 2831 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 92% | 56,014 psi | 88% | 2699 fps | 99.5% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 25.6"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2700 | <<locked>> | 80% | 50,763 psi | 80% | 2579 fps | 99.6% |
| Accurate 3100 | <<locked>> | 80% | 33,185 psi | 52% | 2288 fps | 97.3% |
| Accurate 4350 | <<locked>> | 80% | 44,541 psi | 70% | 2562 fps | 100% |
| Accurate MAGPRO | 85.8 gr | 90% | 45,136 psi | 71% | 2661 fps | 95.7% |
| ADI AR 2208 | <<locked>> | 80% | 52,591 psi | 82% | 2588 fps | 100% |
| ADI AR 2209 | <<locked>> | 80% | 37,217 psi | 58% | 2404 fps | 95.8% |
| ADI AR 2213 | <<locked>> | 86% | 40,451 psi | 63% | 2501 fps | 95.4% |
| ADI AR 2217 | <<locked>> | 94% | 38,769 psi | 61% | 2463 fps | 95% |
| ADI AR 2225 | <<locked>> | 92% | 32,547 psi | 51% | 2371 fps | 95.9% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 53,722 psi | 84% | 2610 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 42,656 psi | 67% | 2527 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 80% | 49,153 psi | 77% | 2637 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 37,217 psi | 58% | 2401 fps | 95.9% |
| Alliant Reloder-22 | <<locked>> | 82% | 35,331 psi | 55% | 2398 fps | 95.3% |
| Alliant Reloder-23 | <<locked>> | 80% | 31,792 psi | 50% | 2313 fps | 99.6% |
| Alliant Reloder-25 | <<locked>> | 80% | 27,818 psi | 44% | 2226 fps | 95.4% |
| Alliant Reloder-26 | 77.2 gr | 80% | 34,534 psi | 54% | 2441 fps | 99% |
| Baschieri & Pellagri 109 | <<locked>> | 94% | 51,576 psi | 81% | 2642 fps | 95.3% |
| Bofors RP15 | <<locked>> | 84% | 35,027 psi | 55% | 2434 fps | 95.7% |
| Bofors RP30 | <<locked>> | 92% | 37,347 psi | 59% | 2478 fps | 95.2% |
| Bofors RP5 | <<locked>> | 80% | 33,069 psi | 52% | 2388 fps | 95.1% |
| Bofors RP7 | <<locked>> | 80% | 47,514 psi | 74% | 2526 fps | 99.1% |
| Hodgdon H1000 | <<locked>> | 92% | 37,246 psi | 58% | 2477 fps | 95.9% |
| Hodgdon H414 | <<locked>> | 80% | 50,053 psi | 78% | 2633 fps | 99.7% |
| Hodgdon H4350 | <<locked>> | 80% | 44,860 psi | 70% | 2552 fps | 98.6% |
| Hodgdon H4831 | <<locked>> | 90% | 43,221 psi | 68% | 2509 fps | 95.7% |
| Hodgdon H4831 SC | <<locked>> | 86% | 42,438 psi | 67% | 2493 fps | 95.4% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 40,219 psi | 63% | 2419 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 86% | 32,909 psi | 52% | 2454 fps | 95.4% |
| Hodgdon Superformance | <<locked>> | 80% | 45,469 psi | 71% | 2591 fps | 99.1% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,760 psi | 44% | 1479 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 51,764 psi | 81% | 2602 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 80% | 50,299 psi | 79% | 2549 fps | 99.7% |
| IMR 4350 | <<locked>> | 80% | 42,917 psi | 67% | 2503 fps | 98.8% |
| IMR 4451 Enduron | <<locked>> | 80% | 48,718 psi | 76% | 2585 fps | 99.7% |
| IMR 4831 | <<locked>> | 80% | 38,522 psi | 60% | 2398 fps | 99.6% |
| IMR 4955 Enduron | <<locked>> | 82% | 39,697 psi | 62% | 2444 fps | 95.4% |
| IMR 7828 SSC | <<locked>> | 86% | 41,539 psi | 65% | 2538 fps | 96% |
| Lovex S065 | <<locked>> | 80% | 46,325 psi | 73% | 2502 fps | 99.8% |
| Lovex S070 | <<locked>> | 80% | 44,657 psi | 70% | 2493 fps | 99.2% |
| Lovex S071 | <<locked>> | 80% | 28,601 psi | 45% | 2173 fps | 95.4% |
| Norma 204 | <<locked>> | 80% | 42,699 psi | 67% | 2495 fps | 97.3% |
| Norma 217 | <<locked>> | 96% | 32,953 psi | 52% | 2412 fps | 95.6% |
| Norma MRP | <<locked>> | 80% | 34,418 psi | 54% | 2405 fps | 96.5% |
| Norma URP | <<locked>> | 80% | 43,743 psi | 69% | 2510 fps | 100% |
| Ramshot Grand | 81.1 gr | 84% | 40,306 psi | 63% | 2526 fps | 96% |
| Ramshot Hunter | <<locked>> | 80% | 42,482 psi | 67% | 2505 fps | 99.3% |
| Ramshot Magnum | <<locked>> | 82% | 32,547 psi | 51% | 2332 fps | 95% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,442 psi | 45% | 1516 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 52,156 psi | 82% | 2676 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 44,309 psi | 69% | 2542 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 42,598 psi | 67% | 2557 fps | 99.9% |
| ReloadSwiss RS 76 | <<locked>> | 86% | 31,865 psi | 50% | 2381 fps | 95.4% |
| ReloadSwiss RS 80 | <<locked>> | 98% | 44,759 psi | 70% | 2643 fps | 95.6% |
| Rottweil R 903 | <<locked>> | 80% | 51,503 psi | 81% | 2578 fps | 100% |
| Rottweil R 904 | <<locked>> | 80% | 38,638 psi | 61% | 2386 fps | 95% |
| Rottweil R 905 | <<locked>> | 80% | 36,434 psi | 57% | 2385 fps | 95.8% |
| Rottweil R 907 | <<locked>> | 80% | 47,514 psi | 74% | 2526 fps | 99.1% |
| Shooters World Long Rifle | <<locked>> | 80% | 46,325 psi | 73% | 2502 fps | 99.8% |
| Shooters World SW4350 | <<locked>> | 80% | 44,657 psi | 70% | 2533 fps | 99.4% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 52,692 psi | 83% | 2631 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 51,750 psi | 81% | 2464 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 45,252 psi | 71% | 2452 fps | 99.2% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 36,100 psi | 57% | 2421 fps | 96.3% |
| Somchem S355 | <<locked>> | 80% | 51,329 psi | 80% | 2573 fps | 100% |
| Somchem S361 | <<locked>> | 82% | 41,872 psi | 66% | 2430 fps | 95.2% |
| Somchem S365 | <<locked>> | 80% | 40,654 psi | 64% | 2471 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 37,115 psi | 58% | 2374 fps | 96.9% |
| Unknown powder | <<locked>> | 80% | 46,862 psi | 73% | 2561 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 44,193 psi | 69% | 2430 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 47,050 psi | 74% | 2533 fps | 100% |
| Vihtavuori N165 | <<locked>> | 82% | 33,272 psi | 52% | 2283 fps | 95.1% |
| Vihtavuori N550 | <<locked>> | 80% | 47,514 psi | 74% | 2573 fps | 100% |
| Vihtavuori N555 | <<locked>> | 80% | 35,723 psi | 56% | 2385 fps | 99.5% |
| Vihtavuori N560 | <<locked>> | 86% | 40,422 psi | 63% | 2524 fps | 95% |
| Vihtavuori N565 | <<locked>> | 90% | 39,581 psi | 62% | 2498 fps | 95.1% |
| Vihtavuori N568 | <<locked>> | 98% | 45,208 psi | 71% | 2653 fps | 95.4% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 44,034 psi | 69% | 2469 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 50,053 psi | 78% | 2633 fps | 99.7% |
| Winchester StaBALL HD | <<locked>> | 80% | 28,166 psi | 44% | 2326 fps | 99.7% |
| Winchester Supreme 780 | <<locked>> | 80% | 36,738 psi | 58% | 2366 fps | 95.7% |
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 81 powders for 8.5 mm Messner Mag. loaded with the .338 | 250gr | Woodleigh PP SN. Hodgdon Retumbo delivers the highest muzzle velocity at 2,867 fps; across all powders the maximum-charge window runs from 1,656 fps to 2,867 fps. ADI AR 2217 gives the best case fill at 100 %, and 81 of the 81 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (440 MPa), the top charges use 59–90 %, leaving at least 10 % headroom. The 250.0 gr projectile in 0.338" calls for a 1:16.5 twist; slower twists will usually not stabilise this weight. ADI AR 2217, ADI AR 2225, Alliant Reloder-25 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 Reloder-26, Accurate MAGPRO, Ramshot Grand rank at the top here: for 8.5 mm Messner Mag. with the .338 | 250gr | Woodleigh PP SN they combine a high case fill with complete burn and sit in the upper velocity band. Always begin at the start load and work up in small increments while checking case and primer for pressure signs.