Load Specifications
Load data in caliber .338 Rem. Ultra Mag. with .338 | 250gr | Swift A-Frame bullet and 75 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Winchester StaBALL HD, Vihtavuori N560 and Norma MRP.
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: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 3100 | <<locked>> | 94% | 54,926 psi | 86% | 2602 fps | 100% |
| Accurate 4350 | <<locked>> | 86% | 56,507 psi | 89% | 2635 fps | 100% |
| Accurate MAGPRO | <<locked>> | 94% | 57,493 psi | 90% | 2749 fps | 98.8% |
| ADI AR 2208 | <<locked>> | 82% | 57,261 psi | 90% | 2592 fps | 100% |
| ADI AR 2209 | <<locked>> | 92% | 57,159 psi | 90% | 2687 fps | 99.8% |
| ADI AR 2213 | <<locked>> | 94% | 54,897 psi | 86% | 2694 fps | 99.1% |
| ADI AR 2217ᴾ | <<locked>> | 100% | 49,255 psi | 77% | 2602 fps | 98.6% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 43,816 psi | 69% | 2566 fps | 99.7% |
| Alliant Reloder-16 | <<locked>> | 88% | 57,246 psi | 90% | 2684 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 82% | 54,636 psi | 86% | 2648 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 92% | 56,536 psi | 89% | 2674 fps | 99.8% |
| Alliant Reloder-22 | <<locked>> | 94% | 54,940 psi | 86% | 2690 fps | 99.7% |
| Alliant Reloder-23 | <<locked>> | 96% | 56,144 psi | 88% | 2661 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 55,463 psi | 87% | 2717 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 92% | 56,695 psi | 89% | 2746 fps | 100% |
| Baschieri & Pellagri 109 | <<locked>> | 96% | 56,594 psi | 89% | 2654 fps | 97% |
| Bofors RP15 | <<locked>> | 98% | 57,595 psi | 90% | 2726 fps | 99.9% |
| Bofors RP30ᴾ | <<locked>> | 100% | 51,256 psi | 80% | 2664 fps | 99.1% |
| Bofors RP5 | <<locked>> | 94% | 54,940 psi | 86% | 2690 fps | 99.7% |
| Bofors RP7 | <<locked>> | 84% | 55,216 psi | 87% | 2585 fps | 99.9% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 54,215 psi | 85% | 2677 fps | 99.6% |
| Hodgdon H414 | <<locked>> | 84% | 54,302 psi | 85% | 2631 fps | 100% |
| Hodgdon H4350 | <<locked>> | 84% | 57,043 psi | 89% | 2644 fps | 99.8% |
| Hodgdon H4831 | <<locked>> | 92% | 54,824 psi | 86% | 2638 fps | 98.6% |
| Hodgdon H4831 SC | <<locked>> | 94% | 57,537 psi | 90% | 2674 fps | 98.9% |
| Hodgdon Hybrid 100V | <<locked>> | 90% | 57,493 psi | 90% | 2608 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 54,186 psi | 85% | 2782 fps | 100% |
| Hodgdon Superformance | <<locked>> | 84% | 54,723 psi | 86% | 2667 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,086 psi | 58% | 1640 fps | 100% |
| IMR 4350 | <<locked>> | 88% | 56,666 psi | 89% | 2621 fps | 100% |
| IMR 4451 Enduron | <<locked>> | 84% | 56,623 psi | 89% | 2605 fps | 100% |
| IMR 4831 | <<locked>> | 88% | 56,594 psi | 89% | 2625 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 92% | 55,869 psi | 88% | 2621 fps | 98.8% |
| IMR 7828 SSC | <<locked>> | 96% | 56,434 psi | 88% | 2726 fps | 99.4% |
| IMR 8133 Enduronᴾ | <<locked>> | 100% | 39,407 psi | 62% | 2477 fps | 96.3% |
| Lovex S065 | <<locked>> | 86% | 57,261 psi | 90% | 2602 fps | 100% |
| Lovex S070 | <<locked>> | 86% | 55,376 psi | 87% | 2602 fps | 100% |
| Lovex S071ᴾ | <<locked>> | 100% | 56,188 psi | 88% | 2618 fps | 100% |
| Norma 204 | <<locked>> | 88% | 57,711 psi | 90% | 2674 fps | 99.8% |
| Norma 217ᴾ | <<locked>> | 100% | 39,494 psi | 62% | 2503 fps | 98.5% |
| Norma MRP | <<locked>> | 92% | 54,592 psi | 86% | 2707 fps | 100% |
| Norma URP | <<locked>> | 86% | 54,737 psi | 86% | 2618 fps | 100% |
| Ramshot Grand | <<locked>> | 96% | 57,435 psi | 90% | 2746 fps | 99.6% |
| Ramshot Hunter | <<locked>> | 88% | 57,203 psi | 90% | 2671 fps | 100% |
| Ramshot Magnum | <<locked>> | 98% | 55,550 psi | 87% | 2680 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,942 psi | 59% | 1680 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 86% | 56,507 psi | 89% | 2654 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 86% | 54,665 psi | 86% | 2680 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 55,056 psi | 86% | 2782 fps | 100% |
| ReloadSwiss RS 80ᴾ | <<locked>> | 100% | 49,908 psi | 78% | 2677 fps | 97.8% |
| Rottweil R 903 | <<locked>> | 82% | 56,565 psi | 89% | 2582 fps | 100% |
| Rottweil R 904 | <<locked>> | 90% | 54,694 psi | 86% | 2608 fps | 99% |
| Rottweil R 905 | <<locked>> | 92% | 56,130 psi | 88% | 2667 fps | 99.8% |
| Rottweil R 907 | <<locked>> | 84% | 55,216 psi | 87% | 2585 fps | 99.9% |
| Shooters World Long Rifle | <<locked>> | 86% | 57,261 psi | 90% | 2602 fps | 100% |
| Shooters World SW4350 | <<locked>> | 86% | 55,376 psi | 87% | 2602 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 82% | 56,115 psi | 88% | 2461 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 86% | 56,420 psi | 88% | 2562 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 92% | 55,680 psi | 87% | 2664 fps | 99.8% |
| Somchem S355 | <<locked>> | 82% | 56,188 psi | 88% | 2579 fps | 100% |
| Somchem S361 | <<locked>> | 90% | 56,202 psi | 88% | 2598 fps | 98.7% |
| Somchem S365 | <<locked>> | 88% | 55,158 psi | 86% | 2618 fps | 100% |
| Somchem S385 | <<locked>> | 92% | 56,550 psi | 89% | 2638 fps | 100% |
| Vihtavuori N150 | <<locked>> | 84% | 57,276 psi | 90% | 2549 fps | 100% |
| Vihtavuori N160 | <<locked>> | 86% | 56,652 psi | 89% | 2608 fps | 100% |
| Vihtavuori N165 | <<locked>> | 96% | 56,115 psi | 88% | 2621 fps | 99.9% |
| Vihtavuori N550 | <<locked>> | 86% | 55,666 psi | 87% | 2615 fps | 100% |
| Vihtavuori N555 | <<locked>> | 92% | 54,708 psi | 86% | 2638 fps | 100% |
| Vihtavuori N560 | <<locked>> | 92% | 54,447 psi | 85% | 2703 fps | 98.8% |
| Vihtavuori N565 | <<locked>> | 98% | 54,273 psi | 85% | 2684 fps | 98.9% |
| Vihtavuori N568ᴾ | <<locked>> | 100% | 50,966 psi | 80% | 2680 fps | 97.5% |
| Winchester 6.5 StaBALL | <<locked>> | 86% | 55,970 psi | 88% | 2569 fps | 100% |
| Winchester 760 | <<locked>> | 84% | 54,505 psi | 85% | 2635 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 96% | 53,737 psi | 84% | 2736 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 94% | 56,652 psi | 89% | 2638 fps | 99.7% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 3100 | <<locked>> | 80% | 34,389 psi | 54% | 2264 fps | 98% |
| Accurate 4350 | <<locked>> | 80% | 46,079 psi | 72% | 2487 fps | 100% |
| Accurate MAGPRO | <<locked>> | 86% | 43,265 psi | 68% | 2520 fps | 95.8% |
| ADI AR 2208 | <<locked>> | 80% | 53,751 psi | 84% | 2546 fps | 100% |
| ADI AR 2209 | <<locked>> | 80% | 38,377 psi | 60% | 2375 fps | 96.7% |
| ADI AR 2213 | <<locked>> | 84% | 39,146 psi | 61% | 2418 fps | 95.5% |
| ADI AR 2217 | <<locked>> | 92% | 37,782 psi | 59% | 2385 fps | 95.3% |
| ADI AR 2225 | <<locked>> | 88% | 29,805 psi | 47% | 2241 fps | 95% |
| Alliant Reloder-16 | <<locked>> | 80% | 44,048 psi | 69% | 2493 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 80% | 50,879 psi | 80% | 2595 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 38,421 psi | 60% | 2372 fps | 96.7% |
| Alliant Reloder-22 | <<locked>> | 80% | 34,127 psi | 53% | 2316 fps | 95.3% |
| Alliant Reloder-23 | <<locked>> | 80% | 32,938 psi | 52% | 2290 fps | 99.9% |
| Alliant Reloder-25 | <<locked>> | 80% | 28,747 psi | 45% | 2208 fps | 96.6% |
| Alliant Reloder-26 | <<locked>> | 80% | 36,056 psi | 56% | 2415 fps | 99.5% |
| Baschieri & Pellagri 109 | <<locked>> | 92% | 49,995 psi | 78% | 2549 fps | 95.5% |
| Bofors RP15 | <<locked>> | 82% | 34,098 psi | 53% | 2316 fps | 95.1% |
| Bofors RP30 | <<locked>> | 90% | 36,579 psi | 57% | 2402 fps | 95.5% |
| Bofors RP5 | <<locked>> | 80% | 34,127 psi | 53% | 2316 fps | 95.3% |
| Bofors RP7 | <<locked>> | 80% | 48,559 psi | 76% | 2487 fps | 99.4% |
| Hodgdon H1000 | <<locked>> | 88% | 35,998 psi | 56% | 2349 fps | 95.3% |
| Hodgdon H414 | <<locked>> | 80% | 47,543 psi | 75% | 2530 fps | 99.6% |
| Hodgdon H4350 | <<locked>> | 80% | 50,053 psi | 78% | 2543 fps | 99.3% |
| Hodgdon H4831 | <<locked>> | 84% | 41,814 psi | 66% | 2425 fps | 95.8% |
| Hodgdon H4831 SC | <<locked>> | 84% | 41,060 psi | 64% | 2411 fps | 95.5% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 41,553 psi | 65% | 2385 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 86% | 34,127 psi | 53% | 2388 fps | 95.9% |
| Hodgdon Superformance | <<locked>> | 80% | 47,210 psi | 74% | 2556 fps | 99.5% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,717 psi | 43% | 1467 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 44,150 psi | 69% | 2428 fps | 98.9% |
| IMR 4451 Enduron | <<locked>> | 80% | 49,980 psi | 78% | 2510 fps | 99.8% |
| IMR 4831 | <<locked>> | 80% | 43,758 psi | 69% | 2438 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 82% | 40,886 psi | 64% | 2375 fps | 95.6% |
| IMR 7828 SSC | <<locked>> | 84% | 37,652 psi | 59% | 2398 fps | 95.1% |
| IMR 8133 Enduron | <<locked>> | 98% | 36,869 psi | 58% | 2425 fps | 95.4% |
| Lovex S065 | <<locked>> | 80% | 47,558 psi | 75% | 2464 fps | 100% |
| Lovex S070 | <<locked>> | 80% | 45,963 psi | 72% | 2457 fps | 99.5% |
| Lovex S071 | <<locked>> | 80% | 29,544 psi | 46% | 2152 fps | 96.3% |
| Norma 204 | <<locked>> | 80% | 44,077 psi | 69% | 2464 fps | 98% |
| Norma 217 | <<locked>> | 94% | 32,387 psi | 51% | 2343 fps | 96% |
| Norma MRP | 75.1 gr | 80% | 35,766 psi | 56% | 2382 fps | 97.5% |
| Norma URP | <<locked>> | 80% | 45,107 psi | 71% | 2477 fps | 100% |
| Ramshot Grand | <<locked>> | 84% | 37,231 psi | 58% | 2402 fps | 95.4% |
| Ramshot Hunter | <<locked>> | 80% | 43,918 psi | 69% | 2474 fps | 99.6% |
| Ramshot Magnum | <<locked>> | 84% | 33,112 psi | 52% | 2293 fps | 95.9% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,398 psi | 45% | 1503 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 45,905 psi | 72% | 2507 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 43,990 psi | 69% | 2520 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 84% | 30,980 psi | 49% | 2303 fps | 95.6% |
| ReloadSwiss RS 80 | <<locked>> | 96% | 42,946 psi | 67% | 2556 fps | 96% |
| Rottweil R 903 | <<locked>> | 80% | 53,011 psi | 83% | 2536 fps | 100% |
| Rottweil R 904 | <<locked>> | 80% | 39,639 psi | 62% | 2356 fps | 95.9% |
| Rottweil R 905 | <<locked>> | 80% | 37,652 psi | 59% | 2359 fps | 96.7% |
| Rottweil R 907 | <<locked>> | 80% | 48,559 psi | 76% | 2487 fps | 99.4% |
| Shooters World Long Rifle | <<locked>> | 80% | 47,558 psi | 75% | 2464 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 45,963 psi | 72% | 2457 fps | 99.5% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 52,808 psi | 83% | 2421 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 46,514 psi | 73% | 2418 fps | 99.5% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 37,318 psi | 58% | 2356 fps | 96.6% |
| Somchem S355 | <<locked>> | 80% | 52,721 psi | 83% | 2533 fps | 100% |
| Somchem S361 | <<locked>> | 80% | 40,292 psi | 63% | 2343 fps | 95.2% |
| Somchem S365 | <<locked>> | 80% | 42,119 psi | 66% | 2434 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 38,218 psi | 60% | 2343 fps | 97.6% |
| Vihtavuori N150 | <<locked>> | 80% | 50,517 psi | 79% | 2464 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 46,572 psi | 73% | 2470 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 33,170 psi | 52% | 2231 fps | 95.6% |
| Vihtavuori N550 | <<locked>> | 80% | 45,847 psi | 72% | 2474 fps | 100% |
| Vihtavuori N555 | <<locked>> | 80% | 36,898 psi | 58% | 2356 fps | 99.8% |
| Vihtavuori N560 | 78.8 gr | 84% | 41,278 psi | 65% | 2480 fps | 95.9% |
| Vihtavuori N565 | <<locked>> | 88% | 38,696 psi | 61% | 2418 fps | 95.3% |
| Vihtavuori N568 | <<locked>> | 96% | 44,324 psi | 69% | 2569 fps | 95.8% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 45,513 psi | 71% | 2431 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 47,732 psi | 75% | 2533 fps | 99.7% |
| Winchester StaBALL HD | 74.3 gr | 80% | 29,254 psi | 46% | 2306 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 34,911 psi | 55% | 2274 fps | 95.5% |
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 .338 Rem. Ultra Mag. loaded with the .338 | 250gr | Swift A-Frame. Hodgdon Retumbo delivers the highest muzzle velocity at 2,782 fps; across all powders the maximum-charge window runs from 1,640 fps to 2,782 fps. ADI AR 2217 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 (440 MPa), the top charges use 58–90 %, leaving at least 10 % headroom. The 250.0 gr projectile in 0.338" calls for a 1:15.5 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. Winchester StaBALL HD, Vihtavuori N560, Norma MRP rank at the top here: for .338 Rem. Ultra Mag. with the .338 | 250gr | Swift A-Frame 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.