Load Specifications
Load data in caliber .338 Rem. Ultra Mag. with .338 | 275gr | Alaska Bullet Works Kodiak SP SPBC bullet and 76 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Hodgdon Retumbo, ReloadSwiss RS 76 and Winchester StaBALL HD.
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 3100 | <<locked>> | 92% | 54,404 psi | 85% | 2480 fps | 100% |
| Accurate 4350 | <<locked>> | 84% | 55,666 psi | 87% | 2503 fps | 100% |
| Accurate High Country | <<locked>> | 90% | 55,970 psi | 88% | 2618 fps | 99.7% |
| Accurate MAGPRO | <<locked>> | 92% | 56,768 psi | 89% | 2625 fps | 99.3% |
| ADI AR 2209 | <<locked>> | 90% | 56,275 psi | 88% | 2559 fps | 100% |
| ADI AR 2213 | <<locked>> | 92% | 54,099 psi | 85% | 2569 fps | 99.5% |
| ADI AR 2217ᴾ | <<locked>> | 100% | 52,025 psi | 82% | 2536 fps | 99.6% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 46,528 psi | 73% | 2507 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 90% | 56,405 psi | 88% | 2556 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 90% | 56,405 psi | 88% | 2556 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 86% | 56,652 psi | 89% | 2549 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 82% | 57,537 psi | 90% | 2556 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 90% | 55,738 psi | 87% | 2549 fps | 99.9% |
| Alliant Reloder-22 | <<locked>> | 92% | 54,331 psi | 85% | 2566 fps | 99.9% |
| Alliant Reloder-23 | <<locked>> | 94% | 55,753 psi | 87% | 2533 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 98% | 54,998 psi | 86% | 2589 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 90% | 56,159 psi | 88% | 2615 fps | 100% |
| Alliant Reloder-33ᴾ | <<locked>> | 100% | 48,370 psi | 76% | 2549 fps | 96.3% |
| Baschieri & Pellagri 109 | <<locked>> | 94% | 55,651 psi | 87% | 2536 fps | 97.8% |
| Bofors RP15 | <<locked>> | 96% | 57,029 psi | 89% | 2598 fps | 100% |
| Bofors RP30ᴾ | <<locked>> | 100% | 54,607 psi | 86% | 2598 fps | 99.8% |
| Bofors RP5 | <<locked>> | 92% | 54,331 psi | 85% | 2566 fps | 99.9% |
| Bofors RP7 | <<locked>> | 84% | 57,537 psi | 90% | 2500 fps | 100% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 57,392 psi | 90% | 2608 fps | 100% |
| Hodgdon H414 | <<locked>> | 84% | 57,145 psi | 90% | 2549 fps | 100% |
| Hodgdon H4350 | <<locked>> | 82% | 55,970 psi | 88% | 2513 fps | 100% |
| Hodgdon H4831 | <<locked>> | 92% | 57,624 psi | 90% | 2562 fps | 99.5% |
| Hodgdon H4831 SC | <<locked>> | 92% | 56,565 psi | 89% | 2549 fps | 99.4% |
| Hodgdon Hybrid 100V | <<locked>> | 88% | 56,855 psi | 89% | 2477 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 57,653 psi | 90% | 2710 fps | 100% |
| Hodgdon Superformance | <<locked>> | 84% | 57,696 psi | 90% | 2589 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,231 psi | 58% | 1562 fps | 100% |
| IMR 4350 | <<locked>> | 86% | 55,724 psi | 87% | 2493 fps | 100% |
| IMR 4451 Enduron | <<locked>> | 82% | 55,317 psi | 87% | 2474 fps | 100% |
| IMR 4831 | <<locked>> | 86% | 55,811 psi | 87% | 2493 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 90% | 54,897 psi | 86% | 2493 fps | 99.2% |
| IMR 7828 SSC | <<locked>> | 94% | 55,782 psi | 87% | 2602 fps | 99.7% |
| IMR 8133 Enduronᴾ | <<locked>> | 100% | 42,032 psi | 66% | 2428 fps | 98.1% |
| Lovex S065 | <<locked>> | 84% | 56,260 psi | 88% | 2474 fps | 100% |
| Lovex S070 | <<locked>> | 84% | 54,534 psi | 85% | 2474 fps | 100% |
| Lovex S071 | <<locked>> | 98% | 55,666 psi | 87% | 2497 fps | 100% |
| Norma 204 | <<locked>> | 86% | 56,753 psi | 89% | 2546 fps | 99.9% |
| Norma 217ᴾ | <<locked>> | 100% | 42,322 psi | 66% | 2451 fps | 99.6% |
| Norma MRP | <<locked>> | 90% | 54,172 psi | 85% | 2582 fps | 100% |
| Norma URP | <<locked>> | 86% | 57,522 psi | 90% | 2530 fps | 100% |
| Ramshot Grand | <<locked>> | 94% | 56,608 psi | 89% | 2618 fps | 99.9% |
| Ramshot Hunter | <<locked>> | 86% | 56,405 psi | 88% | 2543 fps | 100% |
| Ramshot Magnum | <<locked>> | 96% | 54,969 psi | 86% | 2559 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 38,159 psi | 60% | 1601 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 84% | 55,564 psi | 87% | 2523 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 84% | 53,882 psi | 84% | 2549 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 98% | 54,360 psi | 85% | 2654 fps | 100% |
| ReloadSwiss RS 80ᴾ | <<locked>> | 100% | 53,490 psi | 84% | 2621 fps | 99.1% |
| Rottweil R 904 | <<locked>> | 90% | 57,305 psi | 90% | 2530 fps | 99.7% |
| Rottweil R 905 | <<locked>> | 90% | 55,303 psi | 87% | 2539 fps | 100% |
| Rottweil R 907 | <<locked>> | 84% | 57,537 psi | 90% | 2500 fps | 100% |
| Shooters World Long Rifle | <<locked>> | 84% | 56,260 psi | 88% | 2474 fps | 100% |
| Shooters World SW4350 | <<locked>> | 84% | 54,534 psi | 85% | 2474 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 84% | 55,230 psi | 87% | 2431 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 90% | 54,940 psi | 86% | 2536 fps | 99.9% |
| Somchem S361 | <<locked>> | 88% | 55,129 psi | 86% | 2477 fps | 99.1% |
| Somchem S365 | <<locked>> | 86% | 54,592 psi | 86% | 2487 fps | 100% |
| Somchem S385 | <<locked>> | 90% | 55,854 psi | 88% | 2513 fps | 100% |
| Vihtavuori N150 | <<locked>> | 82% | 56,159 psi | 88% | 2415 fps | 100% |
| Vihtavuori N160 | <<locked>> | 84% | 55,695 psi | 87% | 2477 fps | 100% |
| Vihtavuori N165 | <<locked>> | 94% | 55,521 psi | 87% | 2500 fps | 100% |
| Vihtavuori N550 | <<locked>> | 84% | 54,868 psi | 86% | 2484 fps | 100% |
| Vihtavuori N555 | <<locked>> | 90% | 54,360 psi | 85% | 2513 fps | 100% |
| Vihtavuori N560 | <<locked>> | 92% | 57,667 psi | 90% | 2631 fps | 99.6% |
| Vihtavuori N565 | <<locked>> | 98% | 57,638 psi | 90% | 2615 fps | 99.7% |
| Vihtavuori N568ᴾ | <<locked>> | 100% | 54,433 psi | 85% | 2621 fps | 98.8% |
| Vihtavuori N570ᴾ | <<locked>> | 100% | 51,532 psi | 81% | 2615 fps | 96.7% |
| Winchester 6.5 StaBALL | <<locked>> | 84% | 54,969 psi | 86% | 2438 fps | 100% |
| Winchester 760 | <<locked>> | 84% | 57,348 psi | 90% | 2552 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 94% | 53,809 psi | 84% | 2608 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 92% | 55,796 psi | 87% | 2513 fps | 99.9% |
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% | 36,506 psi | 57% | 2205 fps | 99.2% |
| Accurate 4350 | <<locked>> | 80% | 48,689 psi | 76% | 2411 fps | 100% |
| Accurate High Country | <<locked>> | 80% | 39,494 psi | 62% | 2352 fps | 97.1% |
| Accurate MAGPRO | <<locked>> | 82% | 40,045 psi | 63% | 2352 fps | 95.9% |
| ADI AR 2209 | <<locked>> | 80% | 40,437 psi | 63% | 2313 fps | 98.1% |
| ADI AR 2213 | <<locked>> | 80% | 36,042 psi | 56% | 2254 fps | 95.5% |
| ADI AR 2217 | <<locked>> | 88% | 34,867 psi | 55% | 2228 fps | 95.4% |
| ADI AR 2225 | <<locked>> | 84% | 27,789 psi | 44% | 2100 fps | 95.3% |
| Alliant Power Pro Varmint | <<locked>> | 80% | 40,901 psi | 64% | 2316 fps | 98.2% |
| Alliant Power Pro Varmint | <<locked>> | 80% | 40,901 psi | 64% | 2316 fps | 98.2% |
| Alliant Reloder-16 | <<locked>> | 80% | 46,456 psi | 73% | 2415 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 80% | 53,780 psi | 84% | 2510 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 40,524 psi | 64% | 2310 fps | 98.2% |
| Alliant Reloder-22 | <<locked>> | 80% | 36,274 psi | 57% | 2264 fps | 97.2% |
| Alliant Reloder-23 | <<locked>> | 80% | 34,998 psi | 55% | 2224 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 30,414 psi | 48% | 2159 fps | 98.4% |
| Alliant Reloder-26 | <<locked>> | 80% | 38,537 psi | 60% | 2356 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 98% | 44,976 psi | 70% | 2493 fps | 95.3% |
| Baschieri & Pellagri 109 | <<locked>> | 88% | 46,180 psi | 72% | 2385 fps | 95.6% |
| Bofors RP15 | <<locked>> | 80% | 33,823 psi | 53% | 2211 fps | 96.2% |
| Bofors RP30 | <<locked>> | 86% | 34,026 psi | 53% | 2244 fps | 95.7% |
| Bofors RP5 | <<locked>> | 80% | 36,274 psi | 57% | 2264 fps | 97.2% |
| Bofors RP7 | <<locked>> | 80% | 50,894 psi | 80% | 2411 fps | 99.9% |
| Hodgdon H1000 | <<locked>> | 84% | 33,301 psi | 52% | 2195 fps | 95.4% |
| Hodgdon H414 | <<locked>> | 80% | 50,096 psi | 79% | 2454 fps | 100% |
| Hodgdon H4350 | <<locked>> | 80% | 52,446 psi | 82% | 2464 fps | 99.8% |
| Hodgdon H4831 | <<locked>> | 80% | 38,508 psi | 60% | 2260 fps | 95.8% |
| Hodgdon H4831 SC | <<locked>> | 80% | 37,782 psi | 59% | 2247 fps | 95.5% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 43,918 psi | 69% | 2310 fps | 100% |
| Hodgdon Retumbo | 72.5 gr | 82% | 31,691 psi | 50% | 2231 fps | 96.1% |
| Hodgdon Superformance | <<locked>> | 80% | 49,879 psi | 78% | 2484 fps | 100% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,949 psi | 44% | 1394 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 46,253 psi | 72% | 2356 fps | 99.6% |
| IMR 4451 Enduron | <<locked>> | 80% | 52,083 psi | 82% | 2428 fps | 100% |
| IMR 4831 | <<locked>> | 80% | 46,079 psi | 72% | 2362 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 40,190 psi | 63% | 2260 fps | 96.5% |
| IMR 7828 SSC | <<locked>> | 80% | 34,809 psi | 55% | 2238 fps | 95.2% |
| IMR 8133 Enduron | <<locked>> | 94% | 34,592 psi | 54% | 2277 fps | 95.6% |
| Lovex S065 | <<locked>> | 80% | 49,661 psi | 78% | 2385 fps | 100% |
| Lovex S070 | <<locked>> | 80% | 48,109 psi | 75% | 2382 fps | 100% |
| Lovex S071 | <<locked>> | 80% | 31,386 psi | 49% | 2100 fps | 97.9% |
| Norma 204 | <<locked>> | 80% | 46,311 psi | 73% | 2395 fps | 99.1% |
| Norma 217 | <<locked>> | 88% | 28,413 psi | 45% | 2142 fps | 95.1% |
| Norma MRP | <<locked>> | 80% | 38,029 psi | 60% | 2323 fps | 98.9% |
| Norma URP | <<locked>> | 80% | 47,485 psi | 74% | 2398 fps | 100% |
| Ramshot Grand | <<locked>> | 80% | 34,258 psi | 54% | 2238 fps | 95.4% |
| Ramshot Hunter | <<locked>> | 80% | 46,209 psi | 72% | 2398 fps | 100% |
| Ramshot Magnum | <<locked>> | 80% | 30,618 psi | 48% | 2139 fps | 95.9% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,689 psi | 45% | 1430 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 48,457 psi | 76% | 2428 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 46,586 psi | 73% | 2448 fps | 100% |
| ReloadSwiss RS 76 | 75.7 gr | 80% | 28,631 psi | 45% | 2149 fps | 95.7% |
| ReloadSwiss RS 80 | <<locked>> | 90% | 36,840 psi | 58% | 2336 fps | 95% |
| Rottweil R 904 | <<locked>> | 80% | 41,756 psi | 65% | 2293 fps | 97.5% |
| Rottweil R 905 | <<locked>> | 80% | 39,827 psi | 62% | 2297 fps | 98.2% |
| Rottweil R 907 | <<locked>> | 80% | 50,894 psi | 80% | 2411 fps | 99.9% |
| Shooters World Long Rifle | <<locked>> | 80% | 49,661 psi | 78% | 2385 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 48,109 psi | 75% | 2382 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 48,631 psi | 76% | 2343 fps | 99.9% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 39,494 psi | 62% | 2293 fps | 98.1% |
| Somchem S361 | <<locked>> | 80% | 42,308 psi | 66% | 2280 fps | 96.9% |
| Somchem S365 | <<locked>> | 80% | 44,730 psi | 70% | 2359 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 40,379 psi | 63% | 2280 fps | 98.9% |
| Vihtavuori N150 | <<locked>> | 80% | 52,794 psi | 83% | 2375 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 48,965 psi | 77% | 2392 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 35,099 psi | 55% | 2175 fps | 97.3% |
| Vihtavuori N550 | <<locked>> | 80% | 48,240 psi | 76% | 2395 fps | 100% |
| Vihtavuori N555 | <<locked>> | 80% | 39,320 psi | 62% | 2290 fps | 100% |
| Vihtavuori N560 | <<locked>> | 80% | 38,130 psi | 60% | 2313 fps | 95.9% |
| Vihtavuori N565 | <<locked>> | 84% | 35,969 psi | 56% | 2260 fps | 95.5% |
| Vihtavuori N568 | <<locked>> | 92% | 41,133 psi | 64% | 2405 fps | 95.9% |
| Vihtavuori N570 | <<locked>> | 98% | 47,921 psi | 75% | 2559 fps | 95.8% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 47,921 psi | 75% | 2352 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 50,270 psi | 79% | 2457 fps | 100% |
| Winchester StaBALL HD | 72.6 gr | 80% | 31,212 psi | 49% | 2257 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 36,970 psi | 58% | 2218 fps | 97.3% |
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 76 powders for .338 Rem. Ultra Mag. loaded with the .338 | 275gr | Alaska Bullet Works Kodiak SP SPBC. Hodgdon Retumbo delivers the highest muzzle velocity at 2,710 fps; across all powders the maximum-charge window runs from 1,562 fps to 2,710 fps. ADI AR 2217 gives the best case fill at 100 %, and 76 of the 76 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 275.0 gr projectile in 0.338" calls for a 1:15.0 twist; slower twists will usually not stabilise this weight. ADI AR 2217, ADI AR 2225, Alliant Reloder-33 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. Hodgdon Retumbo, ReloadSwiss RS 76, Winchester StaBALL HD rank at the top here: for .338 Rem. Ultra Mag. with the .338 | 275gr | Alaska Bullet Works Kodiak SP SPBC 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.