Load Specifications
Load data in caliber .338 Blaser Mag. with .338 | 250gr | Nosler Partition Gold bullet and 98 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are ReloadSwiss RS 70, Alliant Reloder-26 and Alliant Reloder-16.
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: 25.6"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2495 | <<locked>> | 82% | 52,127 psi | 86% | 2467 fps | 100% |
| Accurate 2700 | <<locked>> | 84% | 53,577 psi | 88% | 2533 fps | 99% |
| Accurate 3100ᴾ | <<locked>> | 100% | 50,024 psi | 82% | 2572 fps | 99.6% |
| Accurate 4064 | <<locked>> | 84% | 52,620 psi | 86% | 2520 fps | 100% |
| Accurate 4350 | <<locked>> | 92% | 52,417 psi | 86% | 2615 fps | 100% |
| Accurate MAGPROᴾ | <<locked>> | 100% | 51,764 psi | 85% | 2700 fps | 96.3% |
| ADI AR 2208 | <<locked>> | 86% | 52,866 psi | 87% | 2549 fps | 100% |
| ADI AR 2209 | <<locked>> | 98% | 53,548 psi | 88% | 2657 fps | 98.5% |
| ADI AR 2213ᴾ | <<locked>> | 100% | 51,329 psi | 84% | 2651 fps | 97% |
| Alliant Power Pro 2000-MR | <<locked>> | 82% | 51,663 psi | 85% | 2661 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 86% | 53,330 psi | 88% | 2569 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 84% | 53,679 psi | 88% | 2589 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 94% | 53,432 psi | 88% | 2667 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 90% | 54,505 psi | 89% | 2694 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 98% | 52,779 psi | 87% | 2648 fps | 98.5% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 49,835 psi | 82% | 2651 fps | 98.2% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 47,007 psi | 77% | 2589 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 41,133 psi | 68% | 2523 fps | 99.2% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 53,606 psi | 88% | 2769 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 82% | 54,926 psi | 90% | 2608 fps | 100% |
| Bofors RP15ᴾ | <<locked>> | 100% | 45,745 psi | 75% | 2582 fps | 97.3% |
| Bofors RP3 | <<locked>> | 86% | 54,215 psi | 89% | 2585 fps | 100% |
| Bofors RP5ᴾ | <<locked>> | 100% | 49,835 psi | 82% | 2651 fps | 98.2% |
| Bofors RP7 | <<locked>> | 90% | 53,737 psi | 88% | 2572 fps | 99.2% |
| Hodgdon H380 | <<locked>> | 86% | 54,520 psi | 90% | 2602 fps | 100% |
| Hodgdon H414 | <<locked>> | 92% | 54,911 psi | 90% | 2667 fps | 99.6% |
| Hodgdon H4350 | <<locked>> | 90% | 54,969 psi | 90% | 2628 fps | 98.9% |
| Hodgdon H4831 | <<locked>> | 98% | 51,517 psi | 85% | 2602 fps | 96.4% |
| Hodgdon H4831 SCᴾ | <<locked>> | 100% | 53,896 psi | 88% | 2638 fps | 96.9% |
| Hodgdon Hybrid 100V | <<locked>> | 96% | 53,664 psi | 88% | 2595 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 82% | 52,156 psi | 86% | 2585 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 40,306 psi | 66% | 2546 fps | 96.3% |
| Hodgdon Superformance | <<locked>> | 92% | 54,752 psi | 90% | 2703 fps | 99.5% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,289 psi | 60% | 1575 fps | 100% |
| Hodgdon VARGET | <<locked>> | 82% | 53,432 psi | 88% | 2552 fps | 100% |
| IMR 4064 | <<locked>> | 84% | 52,388 psi | 86% | 2533 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 84% | 55,013 psi | 90% | 2566 fps | 99.5% |
| IMR 4350 | <<locked>> | 94% | 54,273 psi | 89% | 2602 fps | 99.3% |
| IMR 4451 Enduron | <<locked>> | 88% | 52,214 psi | 86% | 2552 fps | 99.3% |
| IMR 4831 | <<locked>> | 94% | 53,142 psi | 87% | 2612 fps | 100% |
| IMR 4895 | <<locked>> | 84% | 55,085 psi | 90% | 2615 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 98% | 53,243 psi | 87% | 2592 fps | 96.9% |
| IMR 7828 SSCᴾ | <<locked>> | 100% | 48,776 psi | 80% | 2625 fps | 96.5% |
| Lovex S060 | <<locked>> | 82% | 54,128 psi | 89% | 2516 fps | 100% |
| Lovex S062 | <<locked>> | 84% | 52,489 psi | 86% | 2526 fps | 100% |
| Lovex S065 | <<locked>> | 90% | 52,098 psi | 86% | 2549 fps | 99.8% |
| Lovex S070 | <<locked>> | 92% | 52,982 psi | 87% | 2585 fps | 99.5% |
| Lovex S071ᴾ | <<locked>> | 100% | 41,597 psi | 68% | 2438 fps | 98.6% |
| Norma 201 | <<locked>> | 82% | 53,853 psi | 88% | 2533 fps | 100% |
| Norma 202 | <<locked>> | 82% | 54,607 psi | 90% | 2530 fps | 100% |
| Norma 203B | <<locked>> | 84% | 52,968 psi | 87% | 2575 fps | 100% |
| Norma 204 | <<locked>> | 94% | 54,766 psi | 90% | 2651 fps | 98.6% |
| Norma MRPᴾ | <<locked>> | 100% | 52,808 psi | 87% | 2730 fps | 99.6% |
| Norma URP | <<locked>> | 94% | 55,013 psi | 90% | 2654 fps | 100% |
| Ramshot Big Game | <<locked>> | 84% | 53,461 psi | 88% | 2602 fps | 100% |
| Ramshot Grandᴾ | <<locked>> | 100% | 48,704 psi | 80% | 2631 fps | 96.8% |
| Ramshot Hunter | <<locked>> | 94% | 53,519 psi | 88% | 2654 fps | 99.9% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 43,250 psi | 71% | 2520 fps | 97.3% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,970 psi | 61% | 1614 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 86% | 54,592 psi | 90% | 2589 fps | 99.8% |
| ReloadSwiss RS 52 | <<locked>> | 82% | 54,476 psi | 89% | 2651 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 88% | 54,215 psi | 89% | 2684 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 92% | 52,315 psi | 86% | 2641 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 94% | 54,592 psi | 90% | 2720 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 39,784 psi | 65% | 2536 fps | 97.3% |
| Rottweil R 902 | <<locked>> | 84% | 54,549 psi | 90% | 2536 fps | 100% |
| Rottweil R 903 | <<locked>> | 88% | 54,085 psi | 89% | 2579 fps | 100% |
| Rottweil R 904 | <<locked>> | 96% | 52,127 psi | 86% | 2582 fps | 97.3% |
| Rottweil R 905 | <<locked>> | 98% | 51,996 psi | 85% | 2635 fps | 98.5% |
| Rottweil R 907 | <<locked>> | 90% | 53,737 psi | 88% | 2572 fps | 99.2% |
| Shooters World Long Rifle | <<locked>> | 90% | 52,098 psi | 86% | 2549 fps | 99.8% |
| Shooters World Precision | <<locked>> | 84% | 52,489 psi | 86% | 2526 fps | 100% |
| Shooters World SW4350 | <<locked>> | 92% | 52,982 psi | 87% | 2585 fps | 99.5% |
| SNPE Vectan SP 11 | <<locked>> | 86% | 52,083 psi | 86% | 2589 fps | 100% |
| SNPE Vectan SP 9 | <<locked>> | 82% | 53,519 psi | 88% | 2566 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 82% | 54,911 psi | 90% | 2467 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 86% | 52,388 psi | 86% | 2434 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 92% | 55,056 psi | 90% | 2549 fps | 99.5% |
| SNPE Vectan Tubal 8000ᴾ | <<locked>> | 100% | 54,868 psi | 90% | 2677 fps | 98.9% |
| Somchem S335 | <<locked>> | 82% | 54,433 psi | 89% | 2467 fps | 100% |
| Somchem S355 | <<locked>> | 88% | 54,157 psi | 89% | 2575 fps | 100% |
| Somchem S361 | <<locked>> | 96% | 53,519 psi | 88% | 2575 fps | 96.7% |
| Somchem S365 | <<locked>> | 96% | 53,795 psi | 88% | 2651 fps | 100% |
| Somchem S385 | <<locked>> | 98% | 52,605 psi | 86% | 2612 fps | 99.1% |
| Vihtavuori N135 | <<locked>> | 84% | 54,882 psi | 90% | 2493 fps | 100% |
| Vihtavuori N140 | <<locked>> | 84% | 54,998 psi | 90% | 2510 fps | 100% |
| Vihtavuori N150 | <<locked>> | 88% | 52,011 psi | 85% | 2507 fps | 100% |
| Vihtavuori N160 | <<locked>> | 92% | 53,534 psi | 88% | 2598 fps | 100% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 48,515 psi | 80% | 2539 fps | 98.2% |
| Vihtavuori N540 | <<locked>> | 84% | 53,142 psi | 87% | 2510 fps | 100% |
| Vihtavuori N550 | <<locked>> | 92% | 52,692 psi | 87% | 2605 fps | 100% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 52,721 psi | 87% | 2661 fps | 100% |
| Vihtavuori N560ᴾ | <<locked>> | 100% | 53,388 psi | 88% | 2717 fps | 97.2% |
| Winchester 6.5 StaBALL | <<locked>> | 92% | 53,229 psi | 87% | 2572 fps | 100% |
| Winchester 760 | <<locked>> | 90% | 51,663 psi | 85% | 2621 fps | 99.4% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 42,337 psi | 70% | 2644 fps | 100% |
| Winchester StaBALL Match | <<locked>> | 82% | 53,505 psi | 88% | 2572 fps | 100% |
| Winchester Supreme 780ᴾ | <<locked>> | 100% | 52,765 psi | 87% | 2608 fps | 98.3% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 25.6"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2495 | <<locked>> | 80% | 48,965 psi | 80% | 2425 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 46,978 psi | 77% | 2434 fps | 98% |
| Accurate 3100 | <<locked>> | 86% | 31,270 psi | 51% | 2228 fps | 95.6% |
| Accurate 4064 | <<locked>> | 80% | 46,369 psi | 76% | 2434 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 34,969 psi | 57% | 2320 fps | 98.5% |
| Accurate MAGPRO | <<locked>> | 98% | 48,182 psi | 79% | 2641 fps | 95.4% |
| ADI AR 2208 | <<locked>> | 80% | 44,092 psi | 72% | 2415 fps | 99.9% |
| ADI AR 2209 | <<locked>> | 88% | 39,001 psi | 64% | 2402 fps | 95.1% |
| ADI AR 2213 | <<locked>> | 96% | 44,918 psi | 74% | 2539 fps | 95.3% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 48,080 psi | 79% | 2605 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 44,251 psi | 73% | 2434 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 47,413 psi | 78% | 2497 fps | 100% |
| Alliant Reloder-16 | 56.9 gr | 80% | 34,505 psi | 57% | 2329 fps | 98.6% |
| Alliant Reloder-17 | <<locked>> | 80% | 38,624 psi | 63% | 2438 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 88% | 38,522 psi | 63% | 2395 fps | 95.1% |
| Alliant Reloder-22 | <<locked>> | 92% | 38,435 psi | 63% | 2441 fps | 95.3% |
| Alliant Reloder-23 | <<locked>> | 80% | 25,150 psi | 41% | 2113 fps | 96.5% |
| Alliant Reloder-25 | <<locked>> | 90% | 30,197 psi | 50% | 2264 fps | 95.4% |
| Alliant Reloder-26 | 64.3 gr | 82% | 28,340 psi | 47% | 2260 fps | 95.6% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 51,329 psi | 84% | 2559 fps | 100% |
| Bofors RP15 | <<locked>> | 96% | 40,306 psi | 66% | 2477 fps | 95.8% |
| Bofors RP3 | <<locked>> | 80% | 44,396 psi | 73% | 2444 fps | 100% |
| Bofors RP5 | <<locked>> | 92% | 38,435 psi | 63% | 2441 fps | 95.3% |
| Bofors RP7 | <<locked>> | 80% | 39,378 psi | 65% | 2333 fps | 96.5% |
| Hodgdon H380 | <<locked>> | 80% | 44,976 psi | 74% | 2457 fps | 99.6% |
| Hodgdon H414 | <<locked>> | 80% | 36,927 psi | 61% | 2359 fps | 96.5% |
| Hodgdon H4350 | <<locked>> | 80% | 40,001 psi | 66% | 2379 fps | 95.9% |
| Hodgdon H4831 | <<locked>> | 96% | 48,167 psi | 79% | 2549 fps | 95.6% |
| Hodgdon H4831 SC | <<locked>> | 96% | 47,123 psi | 77% | 2530 fps | 95.3% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 31,981 psi | 53% | 2234 fps | 99.1% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 48,849 psi | 80% | 2539 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 98% | 37,782 psi | 62% | 2487 fps | 95.2% |
| Hodgdon Superformance | <<locked>> | 80% | 35,824 psi | 59% | 2365 fps | 95.6% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,137 psi | 45% | 1407 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 50,067 psi | 82% | 2507 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 46,369 psi | 76% | 2441 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 80% | 48,646 psi | 80% | 2470 fps | 98.9% |
| IMR 4350 | <<locked>> | 80% | 35,201 psi | 58% | 2270 fps | 95.2% |
| IMR 4451 Enduron | <<locked>> | 80% | 40,828 psi | 67% | 2362 fps | 97.3% |
| IMR 4831 | <<locked>> | 80% | 33,721 psi | 55% | 2277 fps | 98.2% |
| IMR 4895 | <<locked>> | 80% | 48,602 psi | 80% | 2523 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 94% | 47,094 psi | 77% | 2493 fps | 95.5% |
| IMR 7828 SSC | <<locked>> | 98% | 45,585 psi | 75% | 2566 fps | 95.7% |
| Lovex S060 | <<locked>> | 80% | 51,010 psi | 84% | 2474 fps | 100% |
| Lovex S062 | <<locked>> | 80% | 46,514 psi | 76% | 2441 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 38,305 psi | 63% | 2316 fps | 98% |
| Lovex S070 | <<locked>> | 80% | 36,637 psi | 60% | 2300 fps | 96.6% |
| Lovex S071 | <<locked>> | 90% | 30,269 psi | 50% | 2208 fps | 95.2% |
| Norma 201 | <<locked>> | 80% | 50,691 psi | 83% | 2490 fps | 100% |
| Norma 202 | <<locked>> | 80% | 51,198 psi | 84% | 2487 fps | 100% |
| Norma 203B | <<locked>> | 80% | 46,746 psi | 77% | 2484 fps | 100% |
| Norma 204 | <<locked>> | 84% | 39,291 psi | 65% | 2392 fps | 95.1% |
| Norma MRP | <<locked>> | 88% | 35,128 psi | 58% | 2398 fps | 95.7% |
| Norma URP | <<locked>> | 80% | 35,041 psi | 58% | 2316 fps | 98.4% |
| Ramshot Big Game | <<locked>> | 80% | 46,746 psi | 77% | 2507 fps | 100% |
| Ramshot Grand | <<locked>> | 96% | 42,438 psi | 70% | 2516 fps | 95% |
| Ramshot Hunter | <<locked>> | 80% | 33,881 psi | 56% | 2303 fps | 96.4% |
| Ramshot Magnum | <<locked>> | 96% | 37,681 psi | 62% | 2411 fps | 95.6% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,644 psi | 45% | 1440 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 44,918 psi | 74% | 2441 fps | 98.8% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 50,923 psi | 84% | 2602 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 41,060 psi | 67% | 2487 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 34,606 psi | 57% | 2336 fps | 98.1% |
| ReloadSwiss RS 70 | 62.2 gr | 80% | 33,924 psi | 56% | 2343 fps | 97.5% |
| ReloadSwiss RS 76 | <<locked>> | 96% | 34,809 psi | 57% | 2415 fps | 95.1% |
| Rottweil R 902 | <<locked>> | 80% | 48,341 psi | 79% | 2448 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 41,930 psi | 69% | 2398 fps | 100% |
| Rottweil R 904 | <<locked>> | 90% | 43,178 psi | 71% | 2434 fps | 95.2% |
| Rottweil R 905 | <<locked>> | 88% | 37,362 psi | 61% | 2379 fps | 95% |
| Rottweil R 907 | <<locked>> | 80% | 39,378 psi | 65% | 2333 fps | 96.5% |
| Shooters World Long Rifle | <<locked>> | 80% | 38,305 psi | 63% | 2316 fps | 98% |
| Shooters World Precision | <<locked>> | 80% | 46,514 psi | 76% | 2441 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 36,637 psi | 60% | 2300 fps | 96.6% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 42,859 psi | 70% | 2448 fps | 100% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 50,270 psi | 83% | 2520 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 51,634 psi | 85% | 2425 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 43,511 psi | 71% | 2313 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 37,463 psi | 62% | 2264 fps | 96.6% |
| SNPE Vectan Tubal 8000 | <<locked>> | 90% | 39,595 psi | 65% | 2425 fps | 95.7% |
| Somchem S335 | <<locked>> | 80% | 51,300 psi | 84% | 2428 fps | 100% |
| Somchem S355 | <<locked>> | 80% | 42,308 psi | 69% | 2398 fps | 100% |
| Somchem S361 | <<locked>> | 92% | 46,934 psi | 77% | 2474 fps | 95.2% |
| Somchem S365 | <<locked>> | 80% | 31,488 psi | 52% | 2277 fps | 99.8% |
| Somchem S385 | <<locked>> | 86% | 35,781 psi | 59% | 2320 fps | 95.4% |
| Vihtavuori N135 | <<locked>> | 80% | 48,385 psi | 79% | 2415 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 48,733 psi | 80% | 2428 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 40,437 psi | 66% | 2336 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 36,347 psi | 60% | 2313 fps | 98.6% |
| Vihtavuori N165 | <<locked>> | 92% | 37,318 psi | 61% | 2343 fps | 95.4% |
| Vihtavuori N540 | <<locked>> | 80% | 46,978 psi | 77% | 2428 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 35,853 psi | 59% | 2316 fps | 98.3% |
| Vihtavuori N555 | <<locked>> | 80% | 27,296 psi | 45% | 2178 fps | 96.5% |
| Vihtavuori N560 | <<locked>> | 96% | 46,557 psi | 76% | 2605 fps | 95.6% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 35,505 psi | 58% | 2287 fps | 99.7% |
| Winchester 760 | <<locked>> | 80% | 37,115 psi | 61% | 2365 fps | 96.6% |
| Winchester StaBALL HD | <<locked>> | 82% | 23,612 psi | 39% | 2139 fps | 96.1% |
| Winchester StaBALL Match | <<locked>> | 80% | 50,183 psi | 82% | 2526 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 92% | 40,089 psi | 66% | 2402 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 98 powders for .338 Blaser Mag. loaded with the .338 | 250gr | Nosler Partition Gold. Alliant Reloder-26 delivers the highest muzzle velocity at 2,769 fps; across all powders the maximum-charge window runs from 1,575 fps to 2,769 fps. Accurate 3100 gives the best case fill at 100 %, and 98 of the 98 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (420 MPa), the top charges use 60–90 %, leaving at least 10 % headroom. The 250.0 gr projectile in 0.338" calls for a 1:15.0 twist; slower twists will usually not stabilise this weight. Accurate 3100, Accurate MAGPRO, ADI AR 2213 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. ReloadSwiss RS 70, Alliant Reloder-26, Alliant Reloder-16 rank at the top here: for .338 Blaser Mag. with the .338 | 250gr | Nosler Partition Gold 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.