Load Specifications
Load data in caliber 8.5 mm Messner Mag. with .338 | 230gr | Nosler CT FailSafe bullet and 90 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Norma MRP, Vihtavuori N560 and Alliant Reloder-26.
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% | 55,811 psi | 87% | 2756 fps | 99.5% |
| Accurate 3100 | <<locked>> | 98% | 54,636 psi | 86% | 2812 fps | 100% |
| Accurate 4064 | <<locked>> | 82% | 55,637 psi | 87% | 2733 fps | 100% |
| Accurate 4350 | <<locked>> | 90% | 56,695 psi | 89% | 2851 fps | 100% |
| Accurate MAGPRO | <<locked>> | 98% | 56,927 psi | 89% | 2963 fps | 97.8% |
| ADI AR 2208 | <<locked>> | 84% | 55,347 psi | 87% | 2769 fps | 100% |
| ADI AR 2209 | <<locked>> | 96% | 57,377 psi | 90% | 2904 fps | 99.4% |
| ADI AR 2213 | <<locked>> | 98% | 55,085 psi | 86% | 2904 fps | 98.3% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 37,985 psi | 60% | 2635 fps | 97.5% |
| Alliant Power Pro Varmint | <<locked>> | 96% | 57,624 psi | 90% | 2904 fps | 99.4% |
| Alliant Reloder- TS 15.5 | <<locked>> | 84% | 56,260 psi | 88% | 2789 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 82% | 56,463 psi | 88% | 2812 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 92% | 57,464 psi | 90% | 2907 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 86% | 54,969 psi | 86% | 2874 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 96% | 56,840 psi | 89% | 2894 fps | 99.3% |
| Alliant Reloder-22 | <<locked>> | 98% | 54,433 psi | 85% | 2900 fps | 99.2% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 55,158 psi | 86% | 2874 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 47,659 psi | 75% | 2822 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 96% | 55,361 psi | 87% | 2966 fps | 100% |
| Baschieri & Pellagri 109ᴾ | <<locked>> | 100% | 57,580 psi | 90% | 2864 fps | 95.9% |
| Bofors RP15ᴾ | <<locked>> | 100% | 53,432 psi | 84% | 2884 fps | 99% |
| Bofors RP3 | <<locked>> | 84% | 57,232 psi | 90% | 2805 fps | 100% |
| Bofors RP30ᴾ | <<locked>> | 100% | 43,627 psi | 68% | 2746 fps | 96.7% |
| Bofors RP5 | <<locked>> | 98% | 54,433 psi | 85% | 2900 fps | 99.2% |
| Bofors RP7 | <<locked>> | 88% | 56,347 psi | 88% | 2802 fps | 99.7% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 47,326 psi | 74% | 2766 fps | 97.6% |
| Hodgdon H380 | <<locked>> | 84% | 57,406 psi | 90% | 2825 fps | 100% |
| Hodgdon H414 | <<locked>> | 88% | 55,013 psi | 86% | 2854 fps | 99.8% |
| Hodgdon H4350 | <<locked>> | 86% | 54,491 psi | 85% | 2812 fps | 99.2% |
| Hodgdon H4831 | <<locked>> | 96% | 55,274 psi | 87% | 2848 fps | 97.8% |
| Hodgdon H4831 SC | <<locked>> | 96% | 54,012 psi | 85% | 2828 fps | 97.5% |
| Hodgdon Hybrid 100V | <<locked>> | 94% | 57,638 psi | 90% | 2825 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 46,789 psi | 73% | 2871 fps | 98.9% |
| Hodgdon Superformance | <<locked>> | 88% | 55,187 psi | 86% | 2890 fps | 99.8% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,680 psi | 57% | 1732 fps | 100% |
| IMR 4064 | <<locked>> | 82% | 54,824 psi | 86% | 2749 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 82% | 57,145 psi | 90% | 2789 fps | 99.9% |
| IMR 4350 | <<locked>> | 92% | 57,479 psi | 90% | 2835 fps | 99.8% |
| IMR 4451 Enduron | <<locked>> | 86% | 54,549 psi | 85% | 2776 fps | 99.7% |
| IMR 4831 | <<locked>> | 92% | 56,898 psi | 89% | 2841 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 96% | 56,536 psi | 89% | 2831 fps | 98.1% |
| IMR 7828 SSCᴾ | <<locked>> | 100% | 56,275 psi | 88% | 2936 fps | 98.6% |
| Lovex S062 | <<locked>> | 82% | 55,056 psi | 86% | 2743 fps | 100% |
| Lovex S065 | <<locked>> | 88% | 54,868 psi | 86% | 2776 fps | 100% |
| Lovex S070 | <<locked>> | 90% | 56,304 psi | 88% | 2818 fps | 99.9% |
| Lovex S071ᴾ | <<locked>> | 100% | 48,675 psi | 76% | 2723 fps | 99.7% |
| Norma 203B | <<locked>> | 82% | 55,811 psi | 87% | 2799 fps | 100% |
| Norma 204 | <<locked>> | 90% | 54,795 psi | 86% | 2841 fps | 99% |
| Norma MRP | <<locked>> | 96% | 54,128 psi | 85% | 2927 fps | 99.8% |
| Norma URP | <<locked>> | 90% | 55,303 psi | 87% | 2838 fps | 100% |
| Ramshot Big Game | <<locked>> | 82% | 56,666 psi | 89% | 2825 fps | 100% |
| Ramshot Grandᴾ | <<locked>> | 100% | 57,087 psi | 89% | 2959 fps | 99% |
| Ramshot Hunter | <<locked>> | 92% | 57,595 psi | 90% | 2894 fps | 100% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 50,995 psi | 80% | 2831 fps | 99.3% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,463 psi | 59% | 1775 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 84% | 57,246 psi | 90% | 2815 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 84% | 54,505 psi | 85% | 2864 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 90% | 56,594 psi | 89% | 2877 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 90% | 54,882 psi | 86% | 2907 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 46,833 psi | 73% | 2864 fps | 99.5% |
| Rottweil R 902 | <<locked>> | 82% | 56,956 psi | 89% | 2753 fps | 100% |
| Rottweil R 903 | <<locked>> | 86% | 57,493 psi | 90% | 2805 fps | 100% |
| Rottweil R 904 | <<locked>> | 94% | 55,463 psi | 87% | 2822 fps | 98.4% |
| Rottweil R 905 | <<locked>> | 96% | 56,086 psi | 88% | 2877 fps | 99.4% |
| Rottweil R 907 | <<locked>> | 88% | 56,347 psi | 88% | 2802 fps | 99.7% |
| Shooters World Long Rifle | <<locked>> | 88% | 54,868 psi | 86% | 2776 fps | 100% |
| Shooters World Precision | <<locked>> | 82% | 55,056 psi | 86% | 2743 fps | 100% |
| Shooters World SW4350 | <<locked>> | 90% | 56,304 psi | 88% | 2818 fps | 99.9% |
| SNPE Vectan SP 11 | <<locked>> | 84% | 55,245 psi | 87% | 2812 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 84% | 54,462 psi | 85% | 2635 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 88% | 54,230 psi | 85% | 2726 fps | 99.7% |
| SNPE Vectan Tubal 8000 | <<locked>> | 96% | 55,622 psi | 87% | 2874 fps | 99.3% |
| Somchem S355 | <<locked>> | 86% | 57,319 psi | 90% | 2799 fps | 100% |
| Somchem S361 | <<locked>> | 94% | 57,029 psi | 89% | 2815 fps | 98% |
| Somchem S365 | <<locked>> | 92% | 54,868 psi | 86% | 2838 fps | 100% |
| Somchem S385 | <<locked>> | 96% | 56,797 psi | 89% | 2854 fps | 99.7% |
| Vihtavuori N135 | <<locked>> | 82% | 57,609 psi | 90% | 2703 fps | 100% |
| Vihtavuori N140 | <<locked>> | 82% | 57,566 psi | 90% | 2723 fps | 100% |
| Vihtavuori N150 | <<locked>> | 86% | 55,013 psi | 86% | 2723 fps | 100% |
| Vihtavuori N160 | <<locked>> | 90% | 57,217 psi | 90% | 2828 fps | 100% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 56,101 psi | 88% | 2831 fps | 99.5% |
| Vihtavuori N540 | <<locked>> | 82% | 55,796 psi | 87% | 2723 fps | 100% |
| Vihtavuori N550 | <<locked>> | 90% | 56,246 psi | 88% | 2835 fps | 100% |
| Vihtavuori N555 | <<locked>> | 96% | 54,027 psi | 85% | 2851 fps | 100% |
| Vihtavuori N560 | <<locked>> | 96% | 54,230 psi | 85% | 2917 fps | 97.9% |
| Vihtavuori N565ᴾ | <<locked>> | 100% | 49,821 psi | 78% | 2831 fps | 97.3% |
| Winchester 6.5 StaBALL | <<locked>> | 90% | 56,739 psi | 89% | 2792 fps | 100% |
| Winchester 760 | <<locked>> | 88% | 55,216 psi | 87% | 2858 fps | 99.8% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 51,155 psi | 80% | 2953 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 98% | 56,884 psi | 89% | 2848 fps | 99.3% |
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% | 52,359 psi | 82% | 2703 fps | 99.2% |
| Accurate 3100 | <<locked>> | 80% | 29,776 psi | 47% | 2333 fps | 95.3% |
| Accurate 4064 | <<locked>> | 80% | 52,330 psi | 82% | 2687 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 40,350 psi | 63% | 2585 fps | 99.6% |
| Accurate MAGPRO | <<locked>> | 92% | 46,093 psi | 72% | 2779 fps | 95.5% |
| ADI AR 2208 | <<locked>> | 80% | 48,979 psi | 77% | 2671 fps | 100% |
| ADI AR 2209 | <<locked>> | 84% | 38,783 psi | 61% | 2566 fps | 95.6% |
| ADI AR 2213 | <<locked>> | 90% | 42,235 psi | 66% | 2667 fps | 95.3% |
| ADI AR 2225 | <<locked>> | 96% | 33,417 psi | 52% | 2516 fps | 95.5% |
| Alliant Power Pro Varmint | <<locked>> | 84% | 38,972 psi | 61% | 2569 fps | 95.8% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 49,748 psi | 78% | 2694 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 52,953 psi | 83% | 2762 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 39,015 psi | 61% | 2595 fps | 99.7% |
| Alliant Reloder-17 | <<locked>> | 80% | 44,527 psi | 70% | 2713 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 84% | 38,580 psi | 60% | 2566 fps | 95.7% |
| Alliant Reloder-22 | <<locked>> | 86% | 36,463 psi | 57% | 2559 fps | 95.1% |
| Alliant Reloder-23 | <<locked>> | 80% | 28,790 psi | 45% | 2365 fps | 98.5% |
| Alliant Reloder-25 | <<locked>> | 84% | 28,660 psi | 45% | 2375 fps | 95.2% |
| Alliant Reloder-26 | 75.6 gr | 80% | 30,850 psi | 48% | 2480 fps | 97.3% |
| Baschieri & Pellagri 109 | <<locked>> | 98% | 54,099 psi | 85% | 2808 fps | 95.1% |
| Bofors RP15 | <<locked>> | 90% | 38,624 psi | 61% | 2608 fps | 95.8% |
| Bofors RP3 | <<locked>> | 80% | 50,299 psi | 79% | 2707 fps | 100% |
| Bofors RP30 | <<locked>> | 98% | 40,756 psi | 64% | 2687 fps | 95.8% |
| Bofors RP5 | <<locked>> | 86% | 36,463 psi | 57% | 2559 fps | 95.1% |
| Bofors RP7 | <<locked>> | 80% | 43,903 psi | 69% | 2592 fps | 98.1% |
| Hodgdon H1000 | <<locked>> | 96% | 41,292 psi | 65% | 2644 fps | 95.9% |
| Hodgdon H380 | <<locked>> | 80% | 50,575 psi | 79% | 2723 fps | 100% |
| Hodgdon H414 | <<locked>> | 80% | 42,250 psi | 66% | 2635 fps | 98.3% |
| Hodgdon H4350 | <<locked>> | 80% | 45,034 psi | 71% | 2648 fps | 97.7% |
| Hodgdon H4831 | <<locked>> | 90% | 45,107 psi | 71% | 2677 fps | 95.5% |
| Hodgdon H4831 SC | <<locked>> | 90% | 44,251 psi | 69% | 2657 fps | 95.3% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 36,579 psi | 57% | 2484 fps | 99.9% |
| Hodgdon Retumbo | <<locked>> | 92% | 36,114 psi | 57% | 2621 fps | 95.3% |
| Hodgdon Superformance | <<locked>> | 80% | 41,176 psi | 65% | 2651 fps | 97.8% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,470 psi | 43% | 1549 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 51,547 psi | 81% | 2703 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 80% | 53,592 psi | 84% | 2736 fps | 99.7% |
| IMR 4350 | <<locked>> | 80% | 39,465 psi | 62% | 2523 fps | 97.1% |
| IMR 4451 Enduron | <<locked>> | 80% | 45,382 psi | 71% | 2621 fps | 98.7% |
| IMR 4831 | <<locked>> | 80% | 38,711 psi | 61% | 2539 fps | 99.4% |
| IMR 4955 Enduron | <<locked>> | 88% | 44,077 psi | 69% | 2618 fps | 95.4% |
| IMR 7828 SSC | <<locked>> | 92% | 43,047 psi | 67% | 2700 fps | 95.7% |
| Lovex S062 | <<locked>> | 80% | 51,793 psi | 81% | 2694 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 42,931 psi | 67% | 2572 fps | 99.2% |
| Lovex S070 | <<locked>> | 80% | 41,205 psi | 65% | 2559 fps | 98.2% |
| Lovex S071 | <<locked>> | 84% | 29,211 psi | 46% | 2316 fps | 95.1% |
| Norma 203B | <<locked>> | 80% | 52,315 psi | 82% | 2746 fps | 100% |
| Norma 204 | <<locked>> | 80% | 39,044 psi | 61% | 2552 fps | 95.6% |
| Norma MRP | 75.2 gr | 82% | 33,243 psi | 52% | 2510 fps | 95.4% |
| Norma URP | <<locked>> | 80% | 40,001 psi | 63% | 2579 fps | 99.5% |
| Ramshot Big Game | <<locked>> | 80% | 52,924 psi | 83% | 2772 fps | 100% |
| Ramshot Grand | <<locked>> | 90% | 39,987 psi | 63% | 2648 fps | 95% |
| Ramshot Hunter | <<locked>> | 80% | 38,711 psi | 61% | 2569 fps | 98.2% |
| Ramshot Magnum | <<locked>> | 90% | 35,491 psi | 56% | 2530 fps | 95.5% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,094 psi | 44% | 1588 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 50,401 psi | 79% | 2710 fps | 99.7% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 47,268 psi | 74% | 2756 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 40,161 psi | 63% | 2605 fps | 99.4% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 38,682 psi | 61% | 2615 fps | 99.1% |
| ReloadSwiss RS 76 | <<locked>> | 90% | 32,996 psi | 52% | 2536 fps | 95.1% |
| Rottweil R 902 | <<locked>> | 80% | 53,577 psi | 84% | 2703 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 47,456 psi | 74% | 2657 fps | 100% |
| Rottweil R 904 | <<locked>> | 86% | 42,931 psi | 67% | 2605 fps | 95.7% |
| Rottweil R 905 | <<locked>> | 84% | 37,840 psi | 59% | 2549 fps | 95.7% |
| Rottweil R 907 | <<locked>> | 80% | 43,903 psi | 69% | 2592 fps | 98.1% |
| Shooters World Long Rifle | <<locked>> | 80% | 42,931 psi | 67% | 2572 fps | 99.2% |
| Shooters World Precision | <<locked>> | 80% | 51,793 psi | 81% | 2694 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 41,205 psi | 65% | 2559 fps | 98.2% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 48,472 psi | 76% | 2710 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 48,196 psi | 76% | 2549 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 42,003 psi | 66% | 2520 fps | 98.2% |
| SNPE Vectan Tubal 8000 | <<locked>> | 84% | 37,492 psi | 59% | 2543 fps | 95.5% |
| Somchem S355 | <<locked>> | 80% | 47,485 psi | 74% | 2654 fps | 100% |
| Somchem S361 | <<locked>> | 86% | 43,801 psi | 69% | 2595 fps | 95.1% |
| Somchem S365 | <<locked>> | 80% | 36,448 psi | 57% | 2533 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 33,721 psi | 53% | 2425 fps | 95.1% |
| Vihtavuori N135 | <<locked>> | 80% | 54,085 psi | 85% | 2661 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 54,172 psi | 85% | 2677 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 45,440 psi | 71% | 2582 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 41,321 psi | 65% | 2572 fps | 99.6% |
| Vihtavuori N165 | <<locked>> | 86% | 35,433 psi | 56% | 2461 fps | 95.3% |
| Vihtavuori N540 | <<locked>> | 80% | 52,388 psi | 82% | 2677 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 40,828 psi | 64% | 2579 fps | 99.5% |
| Vihtavuori N555 | <<locked>> | 80% | 31,966 psi | 50% | 2438 fps | 98.4% |
| Vihtavuori N560 | 82.6 gr | 90% | 44,237 psi | 69% | 2740 fps | 95.6% |
| Vihtavuori N565 | <<locked>> | 96% | 43,468 psi | 68% | 2717 fps | 95.7% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 40,335 psi | 63% | 2543 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 42,250 psi | 66% | 2635 fps | 98.3% |
| Winchester StaBALL HD | <<locked>> | 80% | 25,425 psi | 40% | 2356 fps | 98.1% |
| Winchester Supreme 780 | <<locked>> | 86% | 37,594 psi | 59% | 2513 fps | 95.3% |
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 90 powders for 8.5 mm Messner Mag. loaded with the .338 | 230gr | Nosler CT FailSafe. Alliant Reloder-26 delivers the highest muzzle velocity at 2,966 fps; across all powders the maximum-charge window runs from 1,732 fps to 2,966 fps. ADI AR 2225 gives the best case fill at 100 %, and 90 of the 90 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (440 MPa), the top charges use 57–90 %, leaving at least 10 % headroom. The 230.0 gr projectile in 0.338" calls for a 1:14.5 twist; slower twists will usually not stabilise this weight. ADI AR 2225, Alliant Reloder-23, 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. Norma MRP, Vihtavuori N560, Alliant Reloder-26 rank at the top here: for 8.5 mm Messner Mag. with the .338 | 230gr | Nosler CT FailSafe 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.