Load Specifications
Load data in caliber .338 Rem. Ultra Mag. with .338 | 250gr | Barnes TSX BT bullet and 83 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: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 3100 | <<locked>> | 96% | 55,825 psi | 87% | 2605 fps | 100% |
| Accurate 4350 | <<locked>> | 88% | 57,421 psi | 90% | 2638 fps | 100% |
| Accurate High Country | <<locked>> | 94% | 57,305 psi | 90% | 2746 fps | 99.4% |
| Accurate MAGPRO | <<locked>> | 94% | 54,346 psi | 85% | 2697 fps | 98.1% |
| ADI AR 2208 | <<locked>> | 82% | 55,230 psi | 87% | 2556 fps | 100% |
| ADI AR 2209 | <<locked>> | 92% | 54,404 psi | 85% | 2641 fps | 99.5% |
| ADI AR 2213 | <<locked>> | 96% | 55,854 psi | 88% | 2694 fps | 99% |
| ADI AR 2217ᴾ | <<locked>> | 100% | 46,659 psi | 73% | 2546 fps | 97.8% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 41,452 psi | 65% | 2510 fps | 99.2% |
| Alliant Power Pro Varmint | <<locked>> | 92% | 54,795 psi | 86% | 2641 fps | 99.5% |
| Alliant Power Pro Varmint | <<locked>> | 92% | 54,795 psi | 86% | 2641 fps | 99.5% |
| Alliant Reloder- TS 15.5 | <<locked>> | 82% | 56,449 psi | 88% | 2572 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 88% | 54,433 psi | 85% | 2638 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 84% | 55,651 psi | 87% | 2651 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 94% | 57,609 psi | 90% | 2680 fps | 99.7% |
| Alliant Reloder-22 | <<locked>> | 96% | 55,608 psi | 87% | 2690 fps | 99.7% |
| Alliant Reloder-23 | <<locked>> | 98% | 56,652 psi | 89% | 2661 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 52,344 psi | 82% | 2667 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 94% | 57,101 psi | 89% | 2746 fps | 100% |
| Baschieri & Pellagri 109 | <<locked>> | 96% | 54,447 psi | 85% | 2605 fps | 96.2% |
| Bofors RP15 | <<locked>> | 98% | 54,578 psi | 86% | 2674 fps | 99.6% |
| Bofors RP3 | <<locked>> | 82% | 57,493 psi | 90% | 2589 fps | 100% |
| Bofors RP30ᴾ | <<locked>> | 100% | 48,167 psi | 75% | 2608 fps | 98.4% |
| Bofors RP5 | <<locked>> | 96% | 55,608 psi | 87% | 2690 fps | 99.7% |
| Bofors RP7 | <<locked>> | 86% | 56,376 psi | 88% | 2589 fps | 99.9% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 51,503 psi | 81% | 2625 fps | 99.1% |
| Hodgdon H380 | <<locked>> | 82% | 57,580 psi | 90% | 2608 fps | 100% |
| Hodgdon H414 | <<locked>> | 86% | 55,405 psi | 87% | 2638 fps | 100% |
| Hodgdon H4350 | <<locked>> | 84% | 54,795 psi | 86% | 2602 fps | 99.6% |
| Hodgdon H4831 | <<locked>> | 94% | 55,912 psi | 88% | 2638 fps | 98.5% |
| Hodgdon H4831 SC | <<locked>> | 94% | 54,853 psi | 86% | 2625 fps | 98.4% |
| Hodgdon Hybrid 100V | <<locked>> | 90% | 54,868 psi | 86% | 2569 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 51,198 psi | 80% | 2726 fps | 99.9% |
| Hodgdon Superformance | <<locked>> | 86% | 55,767 psi | 87% | 2674 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,956 psi | 58% | 1624 fps | 100% |
| IMR 4350 | <<locked>> | 88% | 54,418 psi | 85% | 2579 fps | 99.8% |
| IMR 4451 Enduron | <<locked>> | 84% | 54,462 psi | 85% | 2566 fps | 99.9% |
| IMR 4831 | <<locked>> | 90% | 57,624 psi | 90% | 2628 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 94% | 56,942 psi | 89% | 2621 fps | 98.7% |
| IMR 7828 SSC | <<locked>> | 98% | 57,363 psi | 90% | 2726 fps | 99.3% |
| Lovex S065 | <<locked>> | 86% | 55,027 psi | 86% | 2562 fps | 100% |
| Lovex S070 | <<locked>> | 88% | 56,579 psi | 89% | 2605 fps | 100% |
| Lovex S071ᴾ | <<locked>> | 100% | 53,287 psi | 84% | 2572 fps | 100% |
| Norma 204 | <<locked>> | 88% | 55,259 psi | 87% | 2628 fps | 99.5% |
| Norma 217ᴾ | <<locked>> | 100% | 36,985 psi | 58% | 2444 fps | 97.6% |
| Norma MRP | <<locked>> | 94% | 55,405 psi | 87% | 2710 fps | 100% |
| Norma URP | <<locked>> | 88% | 55,825 psi | 87% | 2621 fps | 100% |
| Ramshot Grand | <<locked>> | 96% | 54,143 psi | 85% | 2690 fps | 99.2% |
| Ramshot Hunter | <<locked>> | 88% | 54,665 psi | 86% | 2628 fps | 100% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 56,333 psi | 88% | 2684 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,826 psi | 59% | 1663 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 82% | 57,246 psi | 90% | 2598 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 82% | 55,114 psi | 86% | 2641 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 88% | 57,363 psi | 90% | 2657 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 88% | 55,767 psi | 87% | 2687 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 51,750 psi | 81% | 2726 fps | 100% |
| ReloadSwiss RS 80ᴾ | <<locked>> | 100% | 46,514 psi | 73% | 2615 fps | 96.7% |
| Rottweil R 903 | <<locked>> | 82% | 54,186 psi | 85% | 2543 fps | 100% |
| Rottweil R 904 | <<locked>> | 92% | 55,753 psi | 87% | 2612 fps | 99% |
| Rottweil R 905 | <<locked>> | 94% | 57,174 psi | 90% | 2671 fps | 99.8% |
| Rottweil R 907 | <<locked>> | 86% | 56,376 psi | 88% | 2589 fps | 99.9% |
| Shooters World Long Rifle | <<locked>> | 86% | 55,027 psi | 86% | 2562 fps | 100% |
| Shooters World SW4350 | <<locked>> | 88% | 56,579 psi | 89% | 2605 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 82% | 55,666 psi | 87% | 2598 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 84% | 57,624 psi | 90% | 2467 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 86% | 54,375 psi | 85% | 2523 fps | 99.9% |
| SNPE Vectan Tubal 8000 | <<locked>> | 94% | 56,710 psi | 89% | 2667 fps | 99.7% |
| Somchem S355 | <<locked>> | 84% | 57,392 psi | 90% | 2582 fps | 100% |
| Somchem S361 | <<locked>> | 92% | 57,450 psi | 90% | 2605 fps | 98.6% |
| Somchem S365 | <<locked>> | 90% | 55,970 psi | 88% | 2621 fps | 100% |
| Somchem S385 | <<locked>> | 94% | 57,725 psi | 90% | 2644 fps | 100% |
| Vihtavuori N150 | <<locked>> | 84% | 55,129 psi | 86% | 2513 fps | 100% |
| Vihtavuori N160 | <<locked>> | 88% | 57,682 psi | 90% | 2612 fps | 100% |
| Vihtavuori N165 | <<locked>> | 98% | 57,043 psi | 89% | 2621 fps | 99.9% |
| Vihtavuori N550 | <<locked>> | 88% | 56,956 psi | 89% | 2621 fps | 100% |
| Vihtavuori N555 | <<locked>> | 94% | 55,405 psi | 87% | 2638 fps | 100% |
| Vihtavuori N560 | <<locked>> | 94% | 55,347 psi | 87% | 2707 fps | 98.7% |
| Vihtavuori N565ᴾ | <<locked>> | 100% | 54,926 psi | 86% | 2687 fps | 98.8% |
| Vihtavuori N568ᴾ | <<locked>> | 100% | 47,863 psi | 75% | 2621 fps | 96.4% |
| Winchester 6.5 StaBALL | <<locked>> | 88% | 57,334 psi | 90% | 2575 fps | 100% |
| Winchester 760 | <<locked>> | 86% | 55,622 psi | 87% | 2641 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 98% | 53,780 psi | 84% | 2736 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 96% | 57,740 psi | 90% | 2641 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% | 32,474 psi | 51% | 2218 fps | 97.2% |
| Accurate 4350 | <<locked>> | 80% | 43,729 psi | 69% | 2444 fps | 100% |
| Accurate High Country | <<locked>> | 82% | 37,608 psi | 59% | 2415 fps | 95.1% |
| Accurate MAGPRO | 80.5 gr | 88% | 43,961 psi | 69% | 2526 fps | 95.7% |
| ADI AR 2208 | <<locked>> | 80% | 51,880 psi | 81% | 2510 fps | 100% |
| ADI AR 2209 | <<locked>> | 80% | 36,680 psi | 57% | 2329 fps | 95.8% |
| ADI AR 2213 | <<locked>> | 86% | 39,885 psi | 63% | 2421 fps | 95.4% |
| ADI AR 2217 | <<locked>> | 94% | 38,305 psi | 60% | 2385 fps | 95.1% |
| ADI AR 2225 | <<locked>> | 92% | 32,126 psi | 50% | 2297 fps | 96% |
| Alliant Power Pro Varmint | <<locked>> | 80% | 36,883 psi | 58% | 2333 fps | 95.9% |
| Alliant Power Pro Varmint | <<locked>> | 80% | 36,883 psi | 58% | 2333 fps | 95.9% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 53,011 psi | 83% | 2530 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 41,901 psi | 66% | 2451 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 80% | 48,356 psi | 76% | 2556 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 36,550 psi | 57% | 2326 fps | 95.8% |
| Alliant Reloder-22 | <<locked>> | 82% | 34,693 psi | 54% | 2326 fps | 95.3% |
| Alliant Reloder-23 | <<locked>> | 80% | 31,169 psi | 49% | 2244 fps | 99.6% |
| Alliant Reloder-25 | <<locked>> | 80% | 27,383 psi | 43% | 2159 fps | 95.4% |
| Alliant Reloder-26 | <<locked>> | 80% | 33,895 psi | 53% | 2365 fps | 99% |
| Baschieri & Pellagri 109 | <<locked>> | 94% | 51,213 psi | 80% | 2556 fps | 95.4% |
| Bofors RP15 | <<locked>> | 84% | 34,548 psi | 54% | 2320 fps | 95.1% |
| Bofors RP3 | <<locked>> | 80% | 53,925 psi | 85% | 2546 fps | 100% |
| Bofors RP30 | <<locked>> | 92% | 36,898 psi | 58% | 2402 fps | 95.3% |
| Bofors RP5 | <<locked>> | 82% | 34,693 psi | 54% | 2326 fps | 95.3% |
| Bofors RP7 | <<locked>> | 80% | 46,876 psi | 73% | 2448 fps | 99.1% |
| Hodgdon H1000 | <<locked>> | 90% | 36,680 psi | 57% | 2352 fps | 95.2% |
| Hodgdon H380 | <<locked>> | 80% | 53,853 psi | 84% | 2562 fps | 100% |
| Hodgdon H414 | <<locked>> | 80% | 45,426 psi | 71% | 2487 fps | 99.3% |
| Hodgdon H4350 | <<locked>> | 80% | 48,167 psi | 75% | 2500 fps | 98.9% |
| Hodgdon H4831 | <<locked>> | 86% | 42,641 psi | 67% | 2431 fps | 95.7% |
| Hodgdon H4831 SC | <<locked>> | 86% | 41,843 psi | 66% | 2415 fps | 95.4% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 39,610 psi | 62% | 2346 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 88% | 34,490 psi | 54% | 2385 fps | 95.7% |
| Hodgdon Superformance | <<locked>> | 80% | 44,744 psi | 70% | 2507 fps | 99.1% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,673 psi | 43% | 1450 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 42,337 psi | 66% | 2388 fps | 98.4% |
| IMR 4451 Enduron | <<locked>> | 80% | 48,124 psi | 75% | 2470 fps | 99.5% |
| IMR 4831 | <<locked>> | 80% | 41,771 psi | 65% | 2398 fps | 99.9% |
| IMR 4955 Enduron | <<locked>> | 84% | 41,742 psi | 65% | 2379 fps | 95.6% |
| IMR 7828 SSC | <<locked>> | 86% | 38,261 psi | 60% | 2402 fps | 95% |
| Lovex S065 | <<locked>> | 80% | 45,672 psi | 72% | 2425 fps | 99.8% |
| Lovex S070 | <<locked>> | 80% | 44,063 psi | 69% | 2418 fps | 99.2% |
| Lovex S071 | <<locked>> | 80% | 28,050 psi | 44% | 2110 fps | 95.3% |
| Norma 204 | <<locked>> | 80% | 42,148 psi | 66% | 2421 fps | 97.3% |
| Norma 217 | <<locked>> | 96% | 32,416 psi | 51% | 2336 fps | 95.7% |
| Norma MRP | 71.8 gr | 80% | 33,823 psi | 53% | 2329 fps | 96.5% |
| Norma URP | <<locked>> | 80% | 43,105 psi | 68% | 2434 fps | 100% |
| Ramshot Grand | <<locked>> | 86% | 37,884 psi | 59% | 2405 fps | 95.3% |
| Ramshot Hunter | <<locked>> | 80% | 41,916 psi | 66% | 2431 fps | 99.3% |
| Ramshot Magnum | <<locked>> | 86% | 33,692 psi | 53% | 2297 fps | 95.8% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,195 psi | 44% | 1486 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 53,635 psi | 84% | 2549 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 51,285 psi | 80% | 2592 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 43,569 psi | 68% | 2461 fps | 99.9% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 41,858 psi | 66% | 2477 fps | 99.9% |
| ReloadSwiss RS 76 | <<locked>> | 86% | 31,430 psi | 49% | 2306 fps | 95.5% |
| ReloadSwiss RS 80 | <<locked>> | 98% | 43,294 psi | 68% | 2556 fps | 95.8% |
| Rottweil R 903 | <<locked>> | 80% | 50,792 psi | 80% | 2500 fps | 100% |
| Rottweil R 904 | <<locked>> | 80% | 38,072 psi | 60% | 2313 fps | 95% |
| Rottweil R 905 | <<locked>> | 80% | 35,810 psi | 56% | 2313 fps | 95.8% |
| Rottweil R 907 | <<locked>> | 80% | 46,876 psi | 73% | 2448 fps | 99.1% |
| Shooters World Long Rifle | <<locked>> | 80% | 45,672 psi | 72% | 2425 fps | 99.8% |
| Shooters World SW4350 | <<locked>> | 80% | 44,063 psi | 69% | 2418 fps | 99.2% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 52,069 psi | 82% | 2549 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 51,068 psi | 80% | 2392 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 44,773 psi | 70% | 2379 fps | 99.2% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 35,491 psi | 56% | 2310 fps | 95.6% |
| Somchem S355 | <<locked>> | 80% | 50,604 psi | 79% | 2493 fps | 100% |
| Somchem S361 | <<locked>> | 82% | 41,379 psi | 65% | 2352 fps | 95.2% |
| Somchem S365 | <<locked>> | 80% | 39,943 psi | 63% | 2395 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 36,477 psi | 57% | 2300 fps | 96.9% |
| Vihtavuori N150 | <<locked>> | 80% | 48,501 psi | 76% | 2428 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 44,411 psi | 70% | 2428 fps | 100% |
| Vihtavuori N165 | <<locked>> | 82% | 33,736 psi | 53% | 2238 fps | 95.5% |
| Vihtavuori N550 | <<locked>> | 80% | 43,816 psi | 69% | 2431 fps | 99.9% |
| Vihtavuori N555 | <<locked>> | 80% | 35,027 psi | 55% | 2313 fps | 99.5% |
| Vihtavuori N560 | 77.2 gr | 86% | 41,989 psi | 66% | 2487 fps | 95.8% |
| Vihtavuori N565 | <<locked>> | 90% | 38,986 psi | 61% | 2418 fps | 95.1% |
| Vihtavuori N568 | <<locked>> | 98% | 44,599 psi | 70% | 2566 fps | 95.5% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 43,511 psi | 68% | 2392 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 45,571 psi | 71% | 2490 fps | 99.3% |
| Winchester StaBALL HD | <<locked>> | 80% | 27,702 psi | 43% | 2254 fps | 99.7% |
| Winchester Supreme 780 | <<locked>> | 82% | 35,607 psi | 56% | 2283 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 83 powders for .338 Rem. Ultra Mag. loaded with the .338 | 250gr | Barnes TSX BT. Accurate High Country delivers the highest muzzle velocity at 2,746 fps; across all powders the maximum-charge window runs from 1,624 fps to 2,746 fps. ADI AR 2217 gives the best case fill at 100 %, and 83 of the 83 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 1:12.5 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. Vihtavuori N560, Norma MRP, Accurate MAGPRO rank at the top here: for .338 Rem. Ultra Mag. with the .338 | 250gr | Barnes TSX BT 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.