Load Specifications
Load data in caliber .338 Rem. Ultra Mag. with .338 | 250gr | Berger Hybrid OTM bullet and 85 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 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: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 3100 | <<locked>> | 96% | 55,013 psi | 86% | 2592 fps | 100% |
| Accurate 4350 | <<locked>> | 88% | 56,637 psi | 89% | 2625 fps | 100% |
| Accurate High Country | <<locked>> | 94% | 56,202 psi | 88% | 2730 fps | 99.2% |
| Accurate MAGPRO | <<locked>> | 96% | 57,246 psi | 90% | 2733 fps | 98.5% |
| ADI AR 2208 | <<locked>> | 82% | 54,447 psi | 85% | 2543 fps | 100% |
| ADI AR 2209 | <<locked>> | 94% | 57,261 psi | 90% | 2674 fps | 99.7% |
| ADI AR 2213 | <<locked>> | 96% | 55,056 psi | 86% | 2680 fps | 98.9% |
| ADI AR 2217ᴾ | <<locked>> | 100% | 45,861 psi | 72% | 2526 fps | 97.4% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 40,756 psi | 64% | 2493 fps | 99% |
| Alliant Power Pro Varmint | <<locked>> | 94% | 57,537 psi | 90% | 2674 fps | 99.7% |
| Alliant Power Pro Varmint | <<locked>> | 94% | 57,537 psi | 90% | 2674 fps | 99.7% |
| Alliant Power Pro Varmint | <<locked>> | 94% | 57,537 psi | 90% | 2674 fps | 99.7% |
| Alliant Reloder- TS 15.5 | <<locked>> | 82% | 55,840 psi | 88% | 2566 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 90% | 57,363 psi | 90% | 2674 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 84% | 54,882 psi | 86% | 2641 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 94% | 56,782 psi | 89% | 2664 fps | 99.7% |
| Alliant Reloder-22 | <<locked>> | 96% | 54,781 psi | 86% | 2677 fps | 99.6% |
| Alliant Reloder-23 | <<locked>> | 98% | 55,767 psi | 87% | 2648 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 51,372 psi | 81% | 2654 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 94% | 56,202 psi | 88% | 2733 fps | 100% |
| Baschieri & Pellagri 109 | <<locked>> | 98% | 57,159 psi | 90% | 2641 fps | 96.7% |
| Bofors RP15ᴾ | <<locked>> | 100% | 57,188 psi | 90% | 2707 fps | 99.7% |
| Bofors RP3 | <<locked>> | 82% | 56,652 psi | 89% | 2575 fps | 100% |
| Bofors RP30ᴾ | <<locked>> | 100% | 47,413 psi | 74% | 2595 fps | 98.2% |
| Bofors RP5 | <<locked>> | 96% | 54,781 psi | 86% | 2677 fps | 99.6% |
| Bofors RP7 | <<locked>> | 86% | 55,695 psi | 87% | 2575 fps | 99.8% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 50,618 psi | 79% | 2608 fps | 98.9% |
| Hodgdon H380 | <<locked>> | 82% | 56,869 psi | 89% | 2598 fps | 100% |
| Hodgdon H414 | <<locked>> | 86% | 54,737 psi | 86% | 2625 fps | 100% |
| Hodgdon H4350 | <<locked>> | 86% | 57,609 psi | 90% | 2635 fps | 99.8% |
| Hodgdon H4831 | <<locked>> | 94% | 55,114 psi | 86% | 2625 fps | 98.3% |
| Hodgdon H4831 SC | <<locked>> | 94% | 53,809 psi | 84% | 2605 fps | 98.1% |
| Hodgdon Hybrid 100V | <<locked>> | 92% | 57,580 psi | 90% | 2598 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 50,285 psi | 79% | 2707 fps | 99.8% |
| Hodgdon Superformance | <<locked>> | 86% | 54,897 psi | 86% | 2657 fps | 99.9% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,898 psi | 58% | 1617 fps | 100% |
| IMR 4064 | <<locked>> | 82% | 57,334 psi | 90% | 2569 fps | 100% |
| IMR 4350 | <<locked>> | 90% | 57,232 psi | 90% | 2612 fps | 99.9% |
| IMR 4451 Enduron | <<locked>> | 86% | 57,232 psi | 90% | 2598 fps | 100% |
| IMR 4831 | <<locked>> | 90% | 56,927 psi | 89% | 2615 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 94% | 56,217 psi | 88% | 2608 fps | 98.6% |
| IMR 7828 SSC | <<locked>> | 98% | 56,333 psi | 88% | 2707 fps | 99.1% |
| Lovex S065 | <<locked>> | 86% | 54,331 psi | 85% | 2552 fps | 100% |
| Lovex S070 | <<locked>> | 88% | 55,869 psi | 88% | 2592 fps | 100% |
| Lovex S071ᴾ | <<locked>> | 100% | 52,446 psi | 82% | 2559 fps | 100% |
| Norma 204 | <<locked>> | 88% | 54,404 psi | 85% | 2615 fps | 99.3% |
| Norma 217ᴾ | <<locked>> | 100% | 36,332 psi | 57% | 2428 fps | 97.3% |
| Norma MRP | <<locked>> | 94% | 54,331 psi | 85% | 2694 fps | 100% |
| Norma URP | <<locked>> | 88% | 55,100 psi | 86% | 2612 fps | 100% |
| Ramshot Grand | <<locked>> | 98% | 57,276 psi | 90% | 2730 fps | 99.4% |
| Ramshot Hunter | <<locked>> | 90% | 57,566 psi | 90% | 2664 fps | 100% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 55,361 psi | 87% | 2667 fps | 99.9% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,579 psi | 59% | 1654 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 82% | 56,565 psi | 89% | 2585 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 82% | 54,244 psi | 85% | 2628 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 88% | 56,637 psi | 89% | 2648 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 88% | 54,868 psi | 86% | 2674 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 50,662 psi | 79% | 2707 fps | 100% |
| ReloadSwiss RS 80ᴾ | <<locked>> | 100% | 45,759 psi | 72% | 2598 fps | 96.4% |
| Rottweil R 903 | <<locked>> | 84% | 56,956 psi | 89% | 2575 fps | 100% |
| Rottweil R 904 | <<locked>> | 92% | 55,129 psi | 86% | 2598 fps | 98.8% |
| Rottweil R 905 | <<locked>> | 94% | 56,289 psi | 88% | 2654 fps | 99.7% |
| Rottweil R 907 | <<locked>> | 86% | 55,695 psi | 87% | 2575 fps | 99.8% |
| Shooters World Long Rifle | <<locked>> | 86% | 54,331 psi | 85% | 2552 fps | 100% |
| Shooters World SW4350 | <<locked>> | 88% | 55,869 psi | 88% | 2592 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 82% | 54,911 psi | 86% | 2585 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 84% | 57,029 psi | 89% | 2457 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 88% | 57,101 psi | 89% | 2552 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 94% | 55,825 psi | 87% | 2651 fps | 99.6% |
| Somchem S355 | <<locked>> | 84% | 56,579 psi | 89% | 2569 fps | 100% |
| Somchem S361 | <<locked>> | 92% | 56,782 psi | 89% | 2592 fps | 98.5% |
| Somchem S365 | <<locked>> | 90% | 55,201 psi | 87% | 2612 fps | 100% |
| Somchem S385 | <<locked>> | 94% | 56,695 psi | 89% | 2628 fps | 99.9% |
| Vihtavuori N150 | <<locked>> | 84% | 54,375 psi | 85% | 2500 fps | 100% |
| Vihtavuori N160 | <<locked>> | 88% | 56,985 psi | 89% | 2602 fps | 100% |
| Vihtavuori N165 | <<locked>> | 98% | 56,260 psi | 88% | 2608 fps | 99.8% |
| Vihtavuori N550 | <<locked>> | 88% | 56,072 psi | 88% | 2608 fps | 100% |
| Vihtavuori N555 | <<locked>> | 94% | 54,491 psi | 85% | 2628 fps | 100% |
| Vihtavuori N560 | <<locked>> | 94% | 54,331 psi | 85% | 2690 fps | 98.5% |
| Vihtavuori N565ᴾ | <<locked>> | 100% | 53,954 psi | 85% | 2671 fps | 98.7% |
| Vihtavuori N568ᴾ | <<locked>> | 100% | 46,978 psi | 74% | 2605 fps | 96.1% |
| Winchester 6.5 StaBALL | <<locked>> | 88% | 56,550 psi | 89% | 2566 fps | 100% |
| Winchester 760 | <<locked>> | 86% | 54,940 psi | 86% | 2628 fps | 100% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 56,608 psi | 89% | 2769 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 96% | 56,753 psi | 89% | 2625 fps | 99.6% |
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% | 32,010 psi | 50% | 2205 fps | 97% |
| Accurate 4350 | <<locked>> | 80% | 43,120 psi | 68% | 2431 fps | 100% |
| Accurate High Country | <<locked>> | 84% | 39,726 psi | 62% | 2454 fps | 95.8% |
| Accurate MAGPRO | 79.4 gr | 88% | 43,178 psi | 68% | 2510 fps | 95.4% |
| ADI AR 2208 | <<locked>> | 80% | 51,314 psi | 80% | 2500 fps | 100% |
| ADI AR 2209 | <<locked>> | 80% | 36,085 psi | 57% | 2316 fps | 95.5% |
| ADI AR 2213 | <<locked>> | 86% | 39,334 psi | 62% | 2408 fps | 95.1% |
| ADI AR 2217 | <<locked>> | 96% | 40,292 psi | 63% | 2421 fps | 95.7% |
| ADI AR 2225 | <<locked>> | 92% | 31,589 psi | 50% | 2280 fps | 95.6% |
| Alliant Power Pro Varmint | <<locked>> | 80% | 36,390 psi | 57% | 2320 fps | 95.7% |
| Alliant Power Pro Varmint | <<locked>> | 80% | 36,390 psi | 57% | 2320 fps | 95.7% |
| Alliant Power Pro Varmint | <<locked>> | 80% | 36,390 psi | 57% | 2320 fps | 95.7% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 52,388 psi | 82% | 2520 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 41,336 psi | 65% | 2438 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 80% | 47,543 psi | 75% | 2543 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 36,071 psi | 57% | 2313 fps | 95.6% |
| Alliant Reloder-22 | <<locked>> | 84% | 36,608 psi | 57% | 2365 fps | 96% |
| Alliant Reloder-23 | <<locked>> | 80% | 30,719 psi | 48% | 2231 fps | 99.4% |
| Alliant Reloder-25 | <<locked>> | 80% | 26,905 psi | 42% | 2146 fps | 95% |
| Alliant Reloder-26 | <<locked>> | 80% | 33,272 psi | 52% | 2349 fps | 98.8% |
| Baschieri & Pellagri 109 | <<locked>> | 94% | 50,488 psi | 79% | 2539 fps | 95.1% |
| Bofors RP15 | <<locked>> | 86% | 36,260 psi | 57% | 2356 fps | 95.7% |
| Bofors RP3 | <<locked>> | 80% | 53,113 psi | 83% | 2533 fps | 100% |
| Bofors RP30 | <<locked>> | 92% | 36,201 psi | 57% | 2385 fps | 95% |
| Bofors RP5 | <<locked>> | 84% | 36,608 psi | 57% | 2365 fps | 96% |
| Bofors RP7 | <<locked>> | 80% | 46,180 psi | 72% | 2434 fps | 98.9% |
| Hodgdon H1000 | <<locked>> | 92% | 38,551 psi | 60% | 2388 fps | 95.8% |
| Hodgdon H380 | <<locked>> | 80% | 53,301 psi | 84% | 2552 fps | 100% |
| Hodgdon H414 | <<locked>> | 80% | 44,875 psi | 70% | 2477 fps | 99.2% |
| Hodgdon H4350 | <<locked>> | 80% | 47,442 psi | 74% | 2487 fps | 98.7% |
| Hodgdon H4831 | <<locked>> | 86% | 42,090 psi | 66% | 2418 fps | 95.4% |
| Hodgdon H4831 SC | <<locked>> | 86% | 41,234 psi | 65% | 2402 fps | 95.1% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 39,044 psi | 61% | 2336 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 88% | 33,982 psi | 53% | 2372 fps | 95.3% |
| Hodgdon Superformance | <<locked>> | 80% | 44,092 psi | 69% | 2493 fps | 98.9% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,659 psi | 43% | 1447 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 54,012 psi | 85% | 2526 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 41,698 psi | 65% | 2372 fps | 98.2% |
| IMR 4451 Enduron | <<locked>> | 80% | 47,601 psi | 75% | 2457 fps | 99.4% |
| IMR 4831 | <<locked>> | 80% | 41,220 psi | 65% | 2385 fps | 99.9% |
| IMR 4955 Enduron | <<locked>> | 84% | 41,147 psi | 64% | 2365 fps | 95.3% |
| IMR 7828 SSC | <<locked>> | 88% | 40,306 psi | 63% | 2441 fps | 95.6% |
| Lovex S065 | <<locked>> | 80% | 45,150 psi | 71% | 2415 fps | 99.7% |
| Lovex S070 | <<locked>> | 80% | 43,526 psi | 68% | 2405 fps | 99% |
| Lovex S071 | <<locked>> | 80% | 27,557 psi | 43% | 2096 fps | 95% |
| Norma 204 | <<locked>> | 80% | 41,495 psi | 65% | 2405 fps | 97.1% |
| Norma 217 | <<locked>> | 96% | 31,836 psi | 50% | 2320 fps | 95.3% |
| Norma MRP | 70.8 gr | 80% | 33,214 psi | 52% | 2316 fps | 96.2% |
| Norma URP | <<locked>> | 80% | 42,511 psi | 67% | 2425 fps | 99.9% |
| Ramshot Grand | <<locked>> | 88% | 39,987 psi | 63% | 2448 fps | 96% |
| Ramshot Hunter | <<locked>> | 80% | 41,249 psi | 65% | 2418 fps | 99.1% |
| Ramshot Magnum | <<locked>> | 86% | 33,098 psi | 52% | 2280 fps | 95.4% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,181 psi | 44% | 1480 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 52,953 psi | 83% | 2539 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 50,430 psi | 79% | 2582 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 42,873 psi | 67% | 2448 fps | 99.9% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 41,220 psi | 65% | 2464 fps | 99.8% |
| ReloadSwiss RS 76 | <<locked>> | 86% | 30,879 psi | 48% | 2287 fps | 95% |
| ReloadSwiss RS 80 | <<locked>> | 98% | 42,380 psi | 66% | 2536 fps | 95.4% |
| Rottweil R 903 | <<locked>> | 80% | 50,212 psi | 79% | 2490 fps | 100% |
| Rottweil R 904 | <<locked>> | 82% | 40,001 psi | 63% | 2349 fps | 95.6% |
| Rottweil R 905 | <<locked>> | 80% | 35,317 psi | 55% | 2300 fps | 95.5% |
| Rottweil R 907 | <<locked>> | 80% | 46,180 psi | 72% | 2434 fps | 98.9% |
| Shooters World Long Rifle | <<locked>> | 80% | 45,150 psi | 71% | 2415 fps | 99.7% |
| Shooters World SW4350 | <<locked>> | 80% | 43,526 psi | 68% | 2405 fps | 99% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 51,329 psi | 80% | 2539 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 50,473 psi | 79% | 2379 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 44,150 psi | 69% | 2365 fps | 99% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 35,012 psi | 55% | 2293 fps | 95.4% |
| Somchem S355 | <<locked>> | 80% | 50,009 psi | 78% | 2484 fps | 100% |
| Somchem S361 | <<locked>> | 84% | 43,468 psi | 68% | 2388 fps | 95.8% |
| Somchem S365 | <<locked>> | 80% | 39,175 psi | 61% | 2382 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 35,868 psi | 56% | 2287 fps | 96.6% |
| Vihtavuori N150 | <<locked>> | 80% | 47,950 psi | 75% | 2418 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 43,845 psi | 69% | 2415 fps | 100% |
| Vihtavuori N165 | <<locked>> | 82% | 33,156 psi | 52% | 2221 fps | 95.2% |
| Vihtavuori N550 | <<locked>> | 80% | 43,279 psi | 68% | 2421 fps | 99.9% |
| Vihtavuori N555 | <<locked>> | 80% | 34,490 psi | 54% | 2300 fps | 99.4% |
| Vihtavuori N560 | 76.2 gr | 86% | 41,365 psi | 65% | 2474 fps | 95.5% |
| Vihtavuori N565 | <<locked>> | 92% | 41,060 psi | 64% | 2457 fps | 95.8% |
| Vihtavuori N568 | <<locked>> | 98% | 43,787 psi | 69% | 2546 fps | 95.1% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 42,917 psi | 67% | 2382 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 44,875 psi | 70% | 2477 fps | 99.2% |
| Winchester StaBALL HD | <<locked>> | 80% | 27,224 psi | 43% | 2241 fps | 99.5% |
| Winchester Supreme 780 | <<locked>> | 82% | 35,041 psi | 55% | 2267 fps | 95.2% |
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 85 powders for .338 Rem. Ultra Mag. loaded with the .338 | 250gr | Berger Hybrid OTM. Winchester StaBALL HD delivers the highest muzzle velocity at 2,769 fps; across all powders the maximum-charge window runs from 1,617 fps to 2,769 fps. ADI AR 2217 gives the best case fill at 100 %, and 85 of the 85 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 250.0 gr projectile in 0.338" calls for a 1:11.5 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. Norma MRP, Vihtavuori N560, Accurate MAGPRO rank at the top here: for .338 Rem. Ultra Mag. with the .338 | 250gr | Berger Hybrid OTM 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.