Load Specifications
Load data in caliber .338 Rem. Ultra Mag. with .338 | 250gr | Woodleigh RN SN bullet and 74 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Ramshot Grand, Alliant Reloder-26 and Hodgdon Retumbo.
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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Max Load - Barrel Length: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2700 | <<locked>> | 82% | 56,782 psi | 89% | 2572 fps | 100% |
| Accurate 3100 | <<locked>> | 94% | 56,724 psi | 89% | 2631 fps | 100% |
| Accurate 4350 | <<locked>> | 84% | 54,215 psi | 85% | 2608 fps | 100% |
| Accurate MAGPRO | <<locked>> | 94% | 56,159 psi | 88% | 2730 fps | 98.2% |
| ADI AR 2209 | <<locked>> | 90% | 54,839 psi | 86% | 2661 fps | 99.7% |
| ADI AR 2213 | <<locked>> | 94% | 56,391 psi | 88% | 2720 fps | 99.4% |
| ADI AR 2217ᴾ | <<locked>> | 100% | 50,662 psi | 79% | 2631 fps | 99% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 45,266 psi | 71% | 2598 fps | 99.9% |
| Alliant Reloder-16 | <<locked>> | 86% | 54,984 psi | 86% | 2657 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 82% | 56,072 psi | 88% | 2667 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 90% | 54,491 psi | 85% | 2651 fps | 99.7% |
| Alliant Reloder-22 | <<locked>> | 94% | 56,463 psi | 88% | 2717 fps | 99.9% |
| Alliant Reloder-23 | <<locked>> | 94% | 54,128 psi | 85% | 2638 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 57,145 psi | 90% | 2743 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 90% | 54,360 psi | 85% | 2720 fps | 100% |
| Baschieri & Pellagri 109 | <<locked>> | 94% | 54,476 psi | 85% | 2631 fps | 96.8% |
| Bofors RP15 | <<locked>> | 96% | 55,637 psi | 87% | 2703 fps | 99.8% |
| Bofors RP30ᴾ | <<locked>> | 100% | 53,113 psi | 83% | 2694 fps | 99.4% |
| Bofors RP5 | <<locked>> | 94% | 56,463 psi | 88% | 2717 fps | 99.9% |
| Bofors RP7 | <<locked>> | 84% | 56,260 psi | 88% | 2608 fps | 100% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 55,883 psi | 88% | 2707 fps | 99.8% |
| Hodgdon H414 | <<locked>> | 84% | 55,753 psi | 87% | 2657 fps | 100% |
| Hodgdon H4350 | <<locked>> | 82% | 54,621 psi | 86% | 2618 fps | 99.8% |
| Hodgdon H4831 | <<locked>> | 92% | 56,246 psi | 88% | 2661 fps | 98.9% |
| Hodgdon H4831 SC | <<locked>> | 92% | 55,259 psi | 87% | 2648 fps | 98.8% |
| Hodgdon Hybrid 100V | <<locked>> | 88% | 55,347 psi | 87% | 2585 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 56,014 psi | 88% | 2815 fps | 100% |
| Hodgdon Superformance | <<locked>> | 84% | 56,275 psi | 88% | 2694 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,217 psi | 58% | 1654 fps | 100% |
| IMR 4350 | <<locked>> | 86% | 54,563 psi | 86% | 2598 fps | 99.9% |
| IMR 4451 Enduron | <<locked>> | 84% | 57,653 psi | 90% | 2628 fps | 100% |
| IMR 4831 | <<locked>> | 86% | 54,563 psi | 86% | 2602 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 92% | 57,246 psi | 90% | 2648 fps | 99.1% |
| IMR 7828 SSC | <<locked>> | 94% | 54,404 psi | 85% | 2700 fps | 99.2% |
| IMR 8133 Enduronᴾ | <<locked>> | 100% | 40,799 psi | 64% | 2510 fps | 97% |
| Lovex S065 | <<locked>> | 84% | 55,027 psi | 86% | 2579 fps | 100% |
| Lovex S070 | <<locked>> | 86% | 56,565 psi | 89% | 2625 fps | 100% |
| Lovex S071ᴾ | <<locked>> | 100% | 57,711 psi | 90% | 2644 fps | 100% |
| Norma 204 | <<locked>> | 86% | 55,419 psi | 87% | 2648 fps | 99.7% |
| Norma 217ᴾ | <<locked>> | 100% | 40,901 psi | 64% | 2533 fps | 99% |
| Norma MRP | <<locked>> | 92% | 56,405 psi | 88% | 2736 fps | 100% |
| Norma URP | <<locked>> | 86% | 56,072 psi | 88% | 2641 fps | 100% |
| Ramshot Grand | <<locked>> | 94% | 55,056 psi | 86% | 2720 fps | 99.5% |
| Ramshot Hunter | <<locked>> | 86% | 55,056 psi | 86% | 2648 fps | 100% |
| Ramshot Magnum | <<locked>> | 98% | 57,638 psi | 90% | 2710 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 38,058 psi | 60% | 1690 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 84% | 54,230 psi | 85% | 2631 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 86% | 56,304 psi | 88% | 2707 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 56,942 psi | 89% | 2812 fps | 100% |
| ReloadSwiss RS 80ᴾ | <<locked>> | 100% | 51,750 psi | 81% | 2710 fps | 98.3% |
| Rottweil R 904 | <<locked>> | 90% | 55,985 psi | 88% | 2631 fps | 99.3% |
| Rottweil R 905 | <<locked>> | 92% | 57,696 psi | 90% | 2694 fps | 99.9% |
| Rottweil R 907 | <<locked>> | 84% | 56,260 psi | 88% | 2608 fps | 100% |
| Shooters World Long Rifle | <<locked>> | 84% | 55,027 psi | 86% | 2579 fps | 100% |
| Shooters World SW4350 | <<locked>> | 86% | 56,565 psi | 89% | 2625 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 82% | 57,319 psi | 90% | 2480 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 84% | 54,070 psi | 85% | 2536 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 92% | 57,246 psi | 90% | 2690 fps | 99.9% |
| Somchem S355 | <<locked>> | 82% | 57,406 psi | 90% | 2598 fps | 100% |
| Somchem S361 | <<locked>> | 90% | 57,638 psi | 90% | 2628 fps | 99% |
| Somchem S365 | <<locked>> | 88% | 56,739 psi | 89% | 2641 fps | 100% |
| Somchem S385 | <<locked>> | 90% | 54,534 psi | 85% | 2618 fps | 99.9% |
| Vihtavuori N150 | <<locked>> | 82% | 55,027 psi | 86% | 2526 fps | 100% |
| Vihtavuori N160 | <<locked>> | 84% | 54,389 psi | 85% | 2585 fps | 100% |
| Vihtavuori N165 | <<locked>> | 96% | 57,682 psi | 90% | 2648 fps | 100% |
| Vihtavuori N550 | <<locked>> | 86% | 57,058 psi | 89% | 2635 fps | 100% |
| Vihtavuori N555 | <<locked>> | 92% | 56,449 psi | 88% | 2664 fps | 100% |
| Vihtavuori N560 | <<locked>> | 92% | 56,144 psi | 88% | 2733 fps | 99.1% |
| Vihtavuori N565 | <<locked>> | 98% | 56,086 psi | 88% | 2717 fps | 99.2% |
| Vihtavuori N568ᴾ | <<locked>> | 100% | 52,808 psi | 83% | 2713 fps | 98% |
| Winchester 6.5 StaBALL | <<locked>> | 86% | 57,435 psi | 90% | 2589 fps | 100% |
| Winchester 760 | <<locked>> | 84% | 55,956 psi | 88% | 2661 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 96% | 55,912 psi | 88% | 2762 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 92% | 54,375 psi | 85% | 2615 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 2700 | <<locked>> | 80% | 53,214 psi | 83% | 2523 fps | 99.8% |
| Accurate 3100 | <<locked>> | 80% | 35,375 psi | 55% | 2287 fps | 98.4% |
| Accurate 4350 | <<locked>> | 80% | 47,297 psi | 74% | 2510 fps | 100% |
| Accurate MAGPRO | <<locked>> | 88% | 45,440 psi | 71% | 2556 fps | 95.9% |
| ADI AR 2209 | <<locked>> | 80% | 39,349 psi | 62% | 2402 fps | 97.1% |
| ADI AR 2213 | <<locked>> | 82% | 37,521 psi | 59% | 2388 fps | 95.1% |
| ADI AR 2217 | <<locked>> | 92% | 38,769 psi | 61% | 2411 fps | 95.9% |
| ADI AR 2225 | <<locked>> | 88% | 30,661 psi | 48% | 2270 fps | 95.8% |
| Alliant Reloder-16 | <<locked>> | 80% | 45,266 psi | 71% | 2516 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 80% | 52,359 psi | 82% | 2618 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 39,421 psi | 62% | 2398 fps | 97.2% |
| Alliant Reloder-22 | <<locked>> | 80% | 35,230 psi | 55% | 2346 fps | 95.9% |
| Alliant Reloder-23 | <<locked>> | 80% | 33,953 psi | 53% | 2313 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 29,544 psi | 46% | 2234 fps | 97.1% |
| Alliant Reloder-26 | 79.3 gr | 80% | 37,260 psi | 58% | 2441 fps | 99.7% |
| Baschieri & Pellagri 109 | <<locked>> | 90% | 48,124 psi | 75% | 2526 fps | 95.2% |
| Bofors RP15 | <<locked>> | 82% | 35,085 psi | 55% | 2339 fps | 95.7% |
| Bofors RP30 | <<locked>> | 88% | 35,346 psi | 55% | 2375 fps | 95.2% |
| Bofors RP5 | <<locked>> | 80% | 35,230 psi | 55% | 2346 fps | 95.9% |
| Bofors RP7 | <<locked>> | 80% | 49,661 psi | 78% | 2510 fps | 99.6% |
| Hodgdon H1000 | <<locked>> | 88% | 36,999 psi | 58% | 2379 fps | 95.9% |
| Hodgdon H414 | <<locked>> | 80% | 48,805 psi | 76% | 2556 fps | 99.8% |
| Hodgdon H4350 | <<locked>> | 80% | 51,343 psi | 80% | 2569 fps | 99.5% |
| Hodgdon H4831 | <<locked>> | 82% | 40,045 psi | 63% | 2395 fps | 95.3% |
| Hodgdon H4831 SC | <<locked>> | 82% | 39,320 psi | 62% | 2382 fps | 95.1% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 42,714 psi | 67% | 2408 fps | 100% |
| Hodgdon Retumbo | 77.9 gr | 84% | 32,895 psi | 52% | 2359 fps | 95.5% |
| Hodgdon Superformance | <<locked>> | 80% | 48,559 psi | 76% | 2582 fps | 99.7% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,920 psi | 44% | 1476 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 45,165 psi | 71% | 2454 fps | 99.2% |
| IMR 4451 Enduron | <<locked>> | 80% | 51,039 psi | 80% | 2533 fps | 99.9% |
| IMR 4831 | <<locked>> | 80% | 44,889 psi | 70% | 2461 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 39,233 psi | 61% | 2346 fps | 95.3% |
| IMR 7828 SSC | <<locked>> | 84% | 38,682 psi | 61% | 2425 fps | 95.7% |
| IMR 8133 Enduron | <<locked>> | 96% | 35,766 psi | 56% | 2402 fps | 95.1% |
| Lovex S065 | <<locked>> | 80% | 48,660 psi | 76% | 2487 fps | 100% |
| Lovex S070 | <<locked>> | 80% | 47,021 psi | 74% | 2484 fps | 99.7% |
| Lovex S071 | <<locked>> | 80% | 30,516 psi | 48% | 2178 fps | 96.8% |
| Norma 204 | <<locked>> | 80% | 45,252 psi | 71% | 2490 fps | 98.4% |
| Norma 217 | <<locked>> | 92% | 31,386 psi | 49% | 2316 fps | 95.6% |
| Norma MRP | <<locked>> | 80% | 36,912 psi | 58% | 2408 fps | 97.9% |
| Norma URP | <<locked>> | 80% | 46,267 psi | 73% | 2497 fps | 100% |
| Ramshot Grand | 80.2 gr | 84% | 38,392 psi | 60% | 2431 fps | 96% |
| Ramshot Hunter | <<locked>> | 80% | 45,121 psi | 71% | 2497 fps | 99.8% |
| Ramshot Magnum | <<locked>> | 82% | 31,821 psi | 50% | 2264 fps | 95.4% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,442 psi | 45% | 1512 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 47,195 psi | 74% | 2530 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 45,397 psi | 71% | 2549 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 82% | 29,820 psi | 47% | 2274 fps | 95.1% |
| ReloadSwiss RS 80 | <<locked>> | 94% | 41,278 psi | 65% | 2530 fps | 95.6% |
| Rottweil R 904 | <<locked>> | 80% | 40,625 psi | 64% | 2382 fps | 96.3% |
| Rottweil R 905 | <<locked>> | 80% | 38,696 psi | 61% | 2385 fps | 97.2% |
| Rottweil R 907 | <<locked>> | 80% | 49,661 psi | 78% | 2510 fps | 99.6% |
| Shooters World Long Rifle | <<locked>> | 80% | 48,660 psi | 76% | 2487 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 47,021 psi | 74% | 2484 fps | 99.7% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 53,998 psi | 85% | 2441 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 47,485 psi | 74% | 2441 fps | 99.7% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 38,406 psi | 60% | 2379 fps | 97% |
| Somchem S355 | <<locked>> | 80% | 53,925 psi | 85% | 2552 fps | 100% |
| Somchem S361 | <<locked>> | 80% | 41,394 psi | 65% | 2372 fps | 95.8% |
| Somchem S365 | <<locked>> | 80% | 43,410 psi | 68% | 2457 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 39,334 psi | 62% | 2369 fps | 98% |
| Vihtavuori N150 | <<locked>> | 80% | 51,663 psi | 81% | 2484 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 47,718 psi | 75% | 2490 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 34,084 psi | 53% | 2254 fps | 96.1% |
| Vihtavuori N550 | <<locked>> | 80% | 47,079 psi | 74% | 2497 fps | 100% |
| Vihtavuori N555 | <<locked>> | 80% | 38,072 psi | 60% | 2379 fps | 99.9% |
| Vihtavuori N560 | <<locked>> | 82% | 39,711 psi | 62% | 2454 fps | 95.5% |
| Vihtavuori N565 | <<locked>> | 86% | 37,362 psi | 59% | 2392 fps | 95% |
| Vihtavuori N568 | <<locked>> | 94% | 42,670 psi | 67% | 2539 fps | 95.4% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 46,789 psi | 73% | 2451 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 48,994 psi | 77% | 2559 fps | 99.8% |
| Winchester StaBALL HD | <<locked>> | 80% | 30,226 psi | 47% | 2339 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 35,940 psi | 56% | 2300 fps | 96.1% |
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 79 powders for .338 Rem. Ultra Mag. loaded with the .338 | 250gr | Woodleigh RN SN. Hodgdon Retumbo delivers the highest muzzle velocity at 2,815 fps; across all powders the maximum-charge window runs from 1,654 fps to 2,815 fps. ADI AR 2217 gives the best case fill at 100 %, and 79 of the 79 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 1:6.0 twist; slower twists will usually not stabilise this weight. ADI AR 2217, ADI AR 2218, ADI AR 2225 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. Ramshot Grand, Alliant Reloder-26, Hodgdon Retumbo rank at the top here: for .338 Rem. Ultra Mag. with the .338 | 250gr | Woodleigh RN SN they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, ADI AR 2218, Alliant Reloder-33, IMR 7977 Enduron 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.