Load Specifications
Load data in caliber 8.5 mm Messner Mag. with .338 | 250gr | Nosler AccuBond bullet and 86 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Vihtavuori N560, Norma MRP and Accurate MAGPRO.
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>> | 82% | 57,058 psi | 89% | 2654 fps | 99.8% |
| Accurate 3100 | <<locked>> | 98% | 56,014 psi | 88% | 2710 fps | 100% |
| Accurate 4064 | <<locked>> | 82% | 57,014 psi | 89% | 2625 fps | 100% |
| Accurate 4350 | <<locked>> | 88% | 54,360 psi | 85% | 2697 fps | 100% |
| Accurate MAGPRO | <<locked>> | 96% | 54,360 psi | 85% | 2805 fps | 98% |
| ADI AR 2208 | <<locked>> | 84% | 56,478 psi | 89% | 2661 fps | 100% |
| ADI AR 2209 | <<locked>> | 94% | 55,027 psi | 86% | 2749 fps | 99.5% |
| ADI AR 2213 | <<locked>> | 98% | 56,246 psi | 88% | 2805 fps | 99% |
| ADI AR 2217ᴾ | <<locked>> | 100% | 43,961 psi | 69% | 2592 fps | 96.9% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 38,957 psi | 61% | 2559 fps | 98.6% |
| Alliant Reloder- TS 15.5 | <<locked>> | 84% | 57,566 psi | 90% | 2680 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 82% | 57,725 psi | 90% | 2703 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 90% | 55,129 psi | 86% | 2746 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 86% | 56,420 psi | 88% | 2766 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 94% | 54,607 psi | 86% | 2740 fps | 99.5% |
| Alliant Reloder-22 | <<locked>> | 98% | 55,738 psi | 87% | 2799 fps | 99.7% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 56,652 psi | 89% | 2769 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 49,052 psi | 77% | 2726 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 96% | 57,058 psi | 89% | 2864 fps | 100% |
| Baschieri & Pellagri 109 | <<locked>> | 98% | 55,071 psi | 86% | 2713 fps | 96.1% |
| Bofors RP15ᴾ | <<locked>> | 100% | 54,694 psi | 86% | 2785 fps | 99.5% |
| Bofors RP3 | <<locked>> | 82% | 54,926 psi | 86% | 2648 fps | 100% |
| Bofors RP30ᴾ | <<locked>> | 100% | 44,846 psi | 70% | 2661 fps | 97.7% |
| Bofors RP5 | <<locked>> | 98% | 55,738 psi | 87% | 2799 fps | 99.7% |
| Bofors RP7 | <<locked>> | 88% | 57,435 psi | 90% | 2697 fps | 99.9% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 48,283 psi | 76% | 2674 fps | 98.5% |
| Hodgdon H380 | <<locked>> | 82% | 55,158 psi | 86% | 2671 fps | 100% |
| Hodgdon H414 | <<locked>> | 88% | 56,159 psi | 88% | 2749 fps | 100% |
| Hodgdon H4350 | <<locked>> | 86% | 55,680 psi | 87% | 2707 fps | 99.6% |
| Hodgdon H4831 | <<locked>> | 96% | 56,594 psi | 89% | 2749 fps | 98.5% |
| Hodgdon H4831 SC | <<locked>> | 96% | 55,288 psi | 87% | 2730 fps | 98.3% |
| Hodgdon Hybrid 100V | <<locked>> | 92% | 55,593 psi | 87% | 2674 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 48,051 psi | 75% | 2782 fps | 99.5% |
| Hodgdon Superformance | <<locked>> | 88% | 56,594 psi | 89% | 2789 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,869 psi | 58% | 1647 fps | 100% |
| IMR 4064 | <<locked>> | 82% | 55,811 psi | 87% | 2638 fps | 100% |
| IMR 4350 | <<locked>> | 90% | 55,288 psi | 87% | 2684 fps | 99.8% |
| IMR 4451 Enduron | <<locked>> | 86% | 55,695 psi | 87% | 2674 fps | 99.9% |
| IMR 4831 | <<locked>> | 90% | 54,781 psi | 86% | 2687 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 94% | 54,215 psi | 85% | 2680 fps | 98.3% |
| IMR 7828 SSCᴾ | <<locked>> | 100% | 57,696 psi | 90% | 2838 fps | 99.2% |
| Lovex S062 | <<locked>> | 82% | 56,275 psi | 88% | 2631 fps | 100% |
| Lovex S065 | <<locked>> | 88% | 55,970 psi | 88% | 2667 fps | 100% |
| Lovex S070 | <<locked>> | 90% | 57,464 psi | 90% | 2713 fps | 100% |
| Lovex S071ᴾ | <<locked>> | 100% | 49,937 psi | 78% | 2625 fps | 100% |
| Norma 203B | <<locked>> | 82% | 57,014 psi | 89% | 2690 fps | 100% |
| Norma 204 | <<locked>> | 90% | 56,144 psi | 88% | 2740 fps | 99.5% |
| Norma 217ᴾ | <<locked>> | 100% | 34,403 psi | 54% | 2484 fps | 96.6% |
| Norma MRP | <<locked>> | 96% | 55,622 psi | 87% | 2825 fps | 100% |
| Norma URP | <<locked>> | 90% | 56,565 psi | 89% | 2730 fps | 100% |
| Ramshot Grand | <<locked>> | 98% | 54,375 psi | 85% | 2799 fps | 99.1% |
| Ramshot Hunter | <<locked>> | 90% | 55,347 psi | 87% | 2740 fps | 100% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 52,373 psi | 82% | 2740 fps | 99.7% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,550 psi | 59% | 1686 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 82% | 54,752 psi | 86% | 2657 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 84% | 55,854 psi | 88% | 2753 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 88% | 54,302 psi | 85% | 2723 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 90% | 56,144 psi | 88% | 2799 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 48,008 psi | 75% | 2776 fps | 99.9% |
| Rottweil R 903 | <<locked>> | 84% | 55,172 psi | 86% | 2648 fps | 100% |
| Rottweil R 904 | <<locked>> | 94% | 56,521 psi | 89% | 2717 fps | 99% |
| Rottweil R 905 | <<locked>> | 96% | 57,508 psi | 90% | 2779 fps | 99.7% |
| Rottweil R 907 | <<locked>> | 88% | 57,435 psi | 90% | 2697 fps | 99.9% |
| Shooters World Long Rifle | <<locked>> | 88% | 55,970 psi | 88% | 2667 fps | 100% |
| Shooters World Precision | <<locked>> | 82% | 56,275 psi | 88% | 2631 fps | 100% |
| Shooters World SW4350 | <<locked>> | 90% | 57,464 psi | 90% | 2713 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 84% | 56,695 psi | 89% | 2707 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 84% | 55,550 psi | 87% | 2526 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 88% | 55,434 psi | 87% | 2625 fps | 99.9% |
| SNPE Vectan Tubal 8000 | <<locked>> | 96% | 57,029 psi | 89% | 2772 fps | 99.7% |
| Somchem S355 | <<locked>> | 84% | 54,955 psi | 86% | 2641 fps | 100% |
| Somchem S361 | <<locked>> | 92% | 54,505 psi | 85% | 2661 fps | 98.1% |
| Somchem S365 | <<locked>> | 92% | 56,492 psi | 89% | 2730 fps | 100% |
| Somchem S385 | <<locked>> | 94% | 54,447 psi | 85% | 2700 fps | 99.8% |
| Vihtavuori N150 | <<locked>> | 86% | 56,057 psi | 88% | 2615 fps | 100% |
| Vihtavuori N160 | <<locked>> | 88% | 54,897 psi | 86% | 2674 fps | 100% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 57,406 psi | 90% | 2730 fps | 99.8% |
| Vihtavuori N540 | <<locked>> | 82% | 56,913 psi | 89% | 2612 fps | 100% |
| Vihtavuori N550 | <<locked>> | 90% | 57,508 psi | 90% | 2726 fps | 100% |
| Vihtavuori N555 | <<locked>> | 96% | 55,666 psi | 87% | 2746 fps | 100% |
| Vihtavuori N560 | <<locked>> | 96% | 55,637 psi | 87% | 2822 fps | 98.7% |
| Vihtavuori N565ᴾ | <<locked>> | 100% | 51,169 psi | 80% | 2740 fps | 98.2% |
| Winchester 6.5 StaBALL | <<locked>> | 88% | 54,375 psi | 85% | 2638 fps | 100% |
| Winchester 760 | <<locked>> | 88% | 56,376 psi | 88% | 2749 fps | 100% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 53,040 psi | 83% | 2851 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 96% | 54,389 psi | 85% | 2697 fps | 99.4% |
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% | 53,359 psi | 84% | 2602 fps | 99.6% |
| Accurate 3100 | <<locked>> | 80% | 30,734 psi | 48% | 2260 fps | 96.6% |
| Accurate 4064 | <<locked>> | 80% | 53,476 psi | 84% | 2579 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 41,539 psi | 65% | 2497 fps | 99.9% |
| Accurate MAGPRO | 80.6 gr | 90% | 44,164 psi | 69% | 2631 fps | 95.8% |
| ADI AR 2208 | <<locked>> | 80% | 49,937 psi | 78% | 2566 fps | 100% |
| ADI AR 2209 | <<locked>> | 80% | 34,911 psi | 55% | 2375 fps | 95.1% |
| ADI AR 2213 | <<locked>> | 88% | 40,422 psi | 63% | 2526 fps | 95.6% |
| ADI AR 2217 | <<locked>> | 96% | 38,667 psi | 61% | 2480 fps | 95.1% |
| ADI AR 2225 | <<locked>> | 94% | 32,242 psi | 51% | 2392 fps | 96% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 50,865 psi | 80% | 2589 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 54,186 psi | 85% | 2654 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 39,972 psi | 63% | 2503 fps | 99.9% |
| Alliant Reloder-17 | <<locked>> | 80% | 45,730 psi | 72% | 2612 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 34,867 psi | 55% | 2375 fps | 95.2% |
| Alliant Reloder-22 | <<locked>> | 84% | 35,056 psi | 55% | 2421 fps | 95.5% |
| Alliant Reloder-23 | <<locked>> | 80% | 29,588 psi | 46% | 2290 fps | 99.3% |
| Alliant Reloder-25 | <<locked>> | 82% | 27,688 psi | 43% | 2251 fps | 95.7% |
| Alliant Reloder-26 | <<locked>> | 80% | 31,734 psi | 50% | 2405 fps | 98.4% |
| Baschieri & Pellagri 109 | <<locked>> | 96% | 51,793 psi | 81% | 2661 fps | 95.3% |
| Bofors RP15 | <<locked>> | 86% | 34,766 psi | 54% | 2415 fps | 95.2% |
| Bofors RP3 | <<locked>> | 80% | 51,416 psi | 81% | 2602 fps | 100% |
| Bofors RP30 | <<locked>> | 94% | 36,869 psi | 58% | 2497 fps | 95.3% |
| Bofors RP5 | <<locked>> | 84% | 35,056 psi | 55% | 2421 fps | 95.5% |
| Bofors RP7 | <<locked>> | 80% | 44,875 psi | 70% | 2497 fps | 98.8% |
| Hodgdon H1000 | <<locked>> | 92% | 37,014 psi | 58% | 2448 fps | 95.2% |
| Hodgdon H380 | <<locked>> | 80% | 51,532 psi | 81% | 2618 fps | 100% |
| Hodgdon H414 | <<locked>> | 80% | 43,207 psi | 68% | 2539 fps | 99% |
| Hodgdon H4350 | <<locked>> | 80% | 46,021 psi | 72% | 2552 fps | 98.5% |
| Hodgdon H4831 | <<locked>> | 88% | 43,207 psi | 68% | 2533 fps | 95.8% |
| Hodgdon H4831 SC | <<locked>> | 88% | 42,366 psi | 66% | 2516 fps | 95.5% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 37,666 psi | 59% | 2398 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 90% | 34,766 psi | 54% | 2487 fps | 95.8% |
| Hodgdon Superformance | <<locked>> | 80% | 42,192 psi | 66% | 2559 fps | 98.6% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,572 psi | 43% | 1470 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 52,562 psi | 82% | 2595 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 40,451 psi | 63% | 2438 fps | 98% |
| IMR 4451 Enduron | <<locked>> | 80% | 46,311 psi | 73% | 2526 fps | 99.3% |
| IMR 4831 | <<locked>> | 80% | 39,639 psi | 62% | 2444 fps | 99.8% |
| IMR 4955 Enduron | <<locked>> | 86% | 42,322 psi | 66% | 2477 fps | 95.7% |
| IMR 7828 SSC | <<locked>> | 88% | 38,711 psi | 61% | 2500 fps | 95.1% |
| Lovex S062 | <<locked>> | 80% | 52,823 psi | 83% | 2585 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 43,845 psi | 69% | 2477 fps | 99.6% |
| Lovex S070 | <<locked>> | 80% | 42,032 psi | 66% | 2464 fps | 98.8% |
| Lovex S071 | <<locked>> | 82% | 28,268 psi | 44% | 2195 fps | 95.5% |
| Norma 203B | <<locked>> | 80% | 53,548 psi | 84% | 2641 fps | 100% |
| Norma 204 | <<locked>> | 80% | 40,118 psi | 63% | 2467 fps | 96.7% |
| Norma 217 | <<locked>> | 98% | 32,372 psi | 51% | 2431 fps | 95.6% |
| Norma MRP | 70.3 gr | 80% | 31,923 psi | 50% | 2375 fps | 95.8% |
| Norma URP | <<locked>> | 80% | 40,901 psi | 64% | 2484 fps | 99.8% |
| Ramshot Grand | <<locked>> | 88% | 38,290 psi | 60% | 2507 fps | 95.4% |
| Ramshot Hunter | <<locked>> | 80% | 39,813 psi | 62% | 2480 fps | 99% |
| Ramshot Magnum | <<locked>> | 88% | 33,953 psi | 53% | 2395 fps | 95.8% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,079 psi | 44% | 1506 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 51,445 psi | 81% | 2608 fps | 99.9% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 48,544 psi | 76% | 2654 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 41,263 psi | 65% | 2513 fps | 99.8% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 39,726 psi | 62% | 2530 fps | 99.7% |
| ReloadSwiss RS 76 | <<locked>> | 88% | 31,749 psi | 50% | 2408 fps | 95.6% |
| Rottweil R 903 | <<locked>> | 80% | 48,428 psi | 76% | 2552 fps | 100% |
| Rottweil R 904 | <<locked>> | 82% | 38,754 psi | 61% | 2411 fps | 95.2% |
| Rottweil R 905 | <<locked>> | 80% | 34,040 psi | 53% | 2359 fps | 95.2% |
| Rottweil R 907 | <<locked>> | 80% | 44,875 psi | 70% | 2497 fps | 98.8% |
| Shooters World Long Rifle | <<locked>> | 80% | 43,845 psi | 69% | 2477 fps | 99.6% |
| Shooters World Precision | <<locked>> | 80% | 52,823 psi | 83% | 2585 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 42,032 psi | 66% | 2464 fps | 98.8% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 49,705 psi | 78% | 2608 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 49,182 psi | 77% | 2444 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 42,844 psi | 67% | 2428 fps | 98.9% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 33,721 psi | 53% | 2352 fps | 95% |
| Somchem S355 | <<locked>> | 80% | 48,515 psi | 76% | 2552 fps | 100% |
| Somchem S361 | <<locked>> | 84% | 42,047 psi | 66% | 2454 fps | 95.3% |
| Somchem S365 | <<locked>> | 80% | 37,637 psi | 59% | 2444 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 34,577 psi | 54% | 2343 fps | 96.3% |
| Vihtavuori N150 | <<locked>> | 80% | 46,325 psi | 73% | 2480 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 42,424 psi | 66% | 2480 fps | 99.9% |
| Vihtavuori N165 | <<locked>> | 84% | 34,011 psi | 53% | 2329 fps | 95.7% |
| Vihtavuori N540 | <<locked>> | 80% | 53,287 psi | 84% | 2566 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 41,698 psi | 65% | 2484 fps | 99.8% |
| Vihtavuori N555 | <<locked>> | 80% | 33,083 psi | 52% | 2359 fps | 99.2% |
| Vihtavuori N560 | 75.6 gr | 86% | 39,639 psi | 62% | 2536 fps | 95% |
| Vihtavuori N565 | <<locked>> | 92% | 39,073 psi | 61% | 2520 fps | 95.2% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 41,278 psi | 65% | 2448 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 43,352 psi | 68% | 2543 fps | 99% |
| Winchester StaBALL HD | <<locked>> | 80% | 26,179 psi | 41% | 2293 fps | 99.3% |
| Winchester Supreme 780 | <<locked>> | 84% | 36,129 psi | 57% | 2379 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 86 powders for 8.5 mm Messner Mag. loaded with the .338 | 250gr | Nosler AccuBond. Alliant Reloder-26 delivers the highest muzzle velocity at 2,864 fps; across all powders the maximum-charge window runs from 1,647 fps to 2,864 fps. ADI AR 2217 gives the best case fill at 100 %, and 86 of the 86 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (440 MPa), the top charges use 54–90 %, leaving at least 10 % headroom. The 250.0 gr projectile in 0.338" calls for a 1:12.5 twist; slower twists will usually not stabilise this weight. ADI AR 2217, ADI AR 2225, Alliant Reloder-23 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. Vihtavuori N560, Norma MRP, Accurate MAGPRO rank at the top here: for 8.5 mm Messner Mag. with the .338 | 250gr | Nosler AccuBond 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.