Load Specifications
Load data in caliber .338 Win Mag. with .338 | 230gr | Nosler CT FailSafe bullet and 99 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Alliant Power Pro 2000-MR, Hodgdon Superformance and Alliant Reloder-17.
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 2015 | <<locked>> | 84% | 55,637 psi | 89% | 2516 fps | 100% |
| Accurate 2495 | <<locked>> | 88% | 54,143 psi | 87% | 2539 fps | 100% |
| Accurate 2520 | <<locked>> | 84% | 54,259 psi | 87% | 2592 fps | 100% |
| Accurate 2700 | <<locked>> | 92% | 54,418 psi | 87% | 2552 fps | 97.4% |
| Accurate 3100ᴾ | <<locked>> | 100% | 41,162 psi | 66% | 2454 fps | 96.5% |
| Accurate 4064 | <<locked>> | 90% | 54,114 psi | 87% | 2585 fps | 100% |
| Accurate 4350 | <<locked>> | 98% | 53,693 psi | 86% | 2667 fps | 99.8% |
| ADI AR 2206H | <<locked>> | 86% | 54,679 psi | 88% | 2618 fps | 100% |
| ADI AR 2208 | <<locked>> | 92% | 55,622 psi | 89% | 2618 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 84% | 53,592 psi | 86% | 2569 fps | 100% |
| Alliant AR-Comp | <<locked>> | 84% | 54,578 psi | 88% | 2543 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 88% | 54,186 psi | 87% | 2730 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 92% | 55,608 psi | 89% | 2638 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 90% | 56,333 psi | 90% | 2661 fps | 100% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 54,998 psi | 88% | 2720 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 96% | 56,260 psi | 90% | 2756 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 39,363 psi | 63% | 2480 fps | 99.2% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 43,859 psi | 70% | 2631 fps | 98.6% |
| Baschieri & Pellagri 107 | <<locked>> | 86% | 54,404 psi | 87% | 2635 fps | 99.8% |
| Bofors RP3 | <<locked>> | 92% | 56,347 psi | 90% | 2654 fps | 100% |
| Bofors RP7 | <<locked>> | 96% | 56,275 psi | 90% | 2628 fps | 98% |
| Hodgdon Benchmark | <<locked>> | 84% | 55,405 psi | 89% | 2552 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 86% | 56,405 psi | 90% | 2644 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 82% | 54,940 psi | 88% | 2694 fps | 100% |
| Hodgdon H322 | <<locked>> | 82% | 53,693 psi | 86% | 2552 fps | 100% |
| Hodgdon H380 | <<locked>> | 90% | 53,708 psi | 86% | 2618 fps | 99.5% |
| Hodgdon H414 | <<locked>> | 94% | 54,723 psi | 88% | 2690 fps | 98.4% |
| Hodgdon H4350 | <<locked>> | 98% | 55,347 psi | 89% | 2651 fps | 97.3% |
| Hodgdon H4895 | <<locked>> | 86% | 55,274 psi | 89% | 2628 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 51,329 psi | 82% | 2605 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 90% | 54,650 psi | 88% | 2661 fps | 100% |
| Hodgdon Superformance | <<locked>> | 96% | 53,606 psi | 86% | 2700 fps | 97.8% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,607 psi | 57% | 1575 fps | 100% |
| Hodgdon VARGET | <<locked>> | 90% | 55,288 psi | 89% | 2612 fps | 100% |
| IMR 3031 | <<locked>> | 88% | 53,838 psi | 86% | 2589 fps | 100% |
| IMR 4064 | <<locked>> | 92% | 54,404 psi | 87% | 2592 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 92% | 53,867 psi | 86% | 2566 fps | 98.1% |
| IMR 4350 | <<locked>> | 98% | 53,113 psi | 85% | 2605 fps | 97.5% |
| IMR 4451 Enduron | <<locked>> | 94% | 54,795 psi | 88% | 2608 fps | 98.2% |
| IMR 4831ᴾ | <<locked>> | 100% | 48,269 psi | 77% | 2572 fps | 99.3% |
| IMR 4895 | <<locked>> | 88% | 54,085 psi | 87% | 2638 fps | 100% |
| IMR 8208 XBR | <<locked>> | 84% | 53,592 psi | 86% | 2569 fps | 100% |
| Lovex D073.6 | <<locked>> | 86% | 54,259 psi | 87% | 2592 fps | 100% |
| Lovex S060 | <<locked>> | 86% | 54,215 psi | 87% | 2549 fps | 100% |
| Lovex S062 | <<locked>> | 90% | 54,897 psi | 88% | 2595 fps | 100% |
| Lovex S065 | <<locked>> | 96% | 54,114 psi | 87% | 2602 fps | 99.1% |
| Lovex S070 | <<locked>> | 98% | 54,897 psi | 88% | 2635 fps | 98.5% |
| Norma 201 | <<locked>> | 86% | 53,374 psi | 86% | 2566 fps | 100% |
| Norma 202 | <<locked>> | 86% | 53,838 psi | 86% | 2566 fps | 100% |
| Norma 203B | <<locked>> | 90% | 55,492 psi | 89% | 2648 fps | 100% |
| Norma 204 | <<locked>> | 98% | 53,563 psi | 86% | 2648 fps | 96.3% |
| Norma MRPᴾ | <<locked>> | 100% | 43,961 psi | 70% | 2592 fps | 96% |
| Norma URPᴾ | <<locked>> | 100% | 56,246 psi | 90% | 2703 fps | 99.9% |
| Ramshot Big Game | <<locked>> | 90% | 55,970 psi | 90% | 2674 fps | 100% |
| Ramshot Hunterᴾ | <<locked>> | 100% | 55,259 psi | 89% | 2707 fps | 99.1% |
| Ramshot TAC | <<locked>> | 84% | 53,679 psi | 86% | 2589 fps | 99.2% |
| Ramshot Wild Boar | <<locked>> | 84% | 53,403 psi | 86% | 2605 fps | 100% |
| Ramshot X-Terminator | <<locked>> | 82% | 54,404 psi | 87% | 2572 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,027 psi | 58% | 1614 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 90% | 53,998 psi | 87% | 2605 fps | 98.6% |
| ReloadSwiss RS 52 | <<locked>> | 86% | 53,200 psi | 85% | 2674 fps | 99.9% |
| ReloadSwiss RS 60 | <<locked>> | 94% | 56,072 psi | 90% | 2753 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 98% | 53,417 psi | 86% | 2690 fps | 99.7% |
| ReloadSwiss RS 70 | <<locked>> | 98% | 52,997 psi | 85% | 2717 fps | 99.5% |
| Rottweil R 901 | <<locked>> | 84% | 54,491 psi | 87% | 2546 fps | 100% |
| Rottweil R 902 | <<locked>> | 88% | 53,954 psi | 87% | 2566 fps | 100% |
| Rottweil R 903 | <<locked>> | 94% | 56,217 psi | 90% | 2648 fps | 100% |
| Rottweil R 907 | <<locked>> | 96% | 56,275 psi | 90% | 2628 fps | 98% |
| Shooters World Long Rifle | <<locked>> | 96% | 54,114 psi | 87% | 2602 fps | 99.1% |
| Shooters World Match Rifle | <<locked>> | 86% | 54,259 psi | 87% | 2592 fps | 100% |
| Shooters World Precision | <<locked>> | 90% | 54,897 psi | 88% | 2595 fps | 100% |
| Shooters World SW4350 | <<locked>> | 98% | 54,897 psi | 88% | 2635 fps | 98.5% |
| SNPE Vectan SP 11 | <<locked>> | 92% | 54,157 psi | 87% | 2654 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 86% | 55,912 psi | 90% | 2621 fps | 99.6% |
| SNPE Vectan SP 9 | <<locked>> | 88% | 56,362 psi | 90% | 2638 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 86% | 54,824 psi | 88% | 2503 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 92% | 54,984 psi | 88% | 2507 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 96% | 54,244 psi | 87% | 2559 fps | 98.1% |
| Somchem S321 | <<locked>> | 82% | 54,781 psi | 88% | 2602 fps | 100% |
| Somchem S335 | <<locked>> | 86% | 54,273 psi | 87% | 2507 fps | 100% |
| Somchem S341 | <<locked>> | 86% | 55,492 psi | 89% | 2612 fps | 100% |
| Somchem S355 | <<locked>> | 94% | 56,391 psi | 90% | 2641 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 50,705 psi | 81% | 2657 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 47,195 psi | 76% | 2549 fps | 96.3% |
| Unknown powder | <<locked>> | 96% | 54,027 psi | 87% | 2664 fps | 99.5% |
| Vihtavuori N130 | <<locked>> | 82% | 54,694 psi | 88% | 2470 fps | 100% |
| Vihtavuori N133 | <<locked>> | 86% | 55,100 psi | 88% | 2490 fps | 100% |
| Vihtavuori N135 | <<locked>> | 88% | 53,664 psi | 86% | 2530 fps | 100% |
| Vihtavuori N140 | <<locked>> | 88% | 54,505 psi | 87% | 2546 fps | 100% |
| Vihtavuori N150 | <<locked>> | 94% | 54,433 psi | 87% | 2579 fps | 100% |
| Vihtavuori N160 | <<locked>> | 98% | 55,361 psi | 89% | 2654 fps | 99.8% |
| Vihtavuori N530 | <<locked>> | 84% | 53,954 psi | 87% | 2569 fps | 100% |
| Vihtavuori N540 | <<locked>> | 90% | 56,043 psi | 90% | 2589 fps | 100% |
| Vihtavuori N550 | <<locked>> | 98% | 54,476 psi | 87% | 2661 fps | 99.7% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 43,279 psi | 69% | 2556 fps | 99.1% |
| Winchester 6.5 StaBALL | <<locked>> | 98% | 55,593 psi | 89% | 2635 fps | 100% |
| Winchester 748 | <<locked>> | 82% | 54,563 psi | 87% | 2621 fps | 100% |
| Winchester 760 | <<locked>> | 94% | 54,723 psi | 88% | 2690 fps | 98.4% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 35,288 psi | 57% | 2490 fps | 99.2% |
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 2015 | <<locked>> | 80% | 49,153 psi | 79% | 2434 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 41,930 psi | 67% | 2372 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 47,471 psi | 76% | 2500 fps | 100% |
| Accurate 2700 | <<locked>> | 86% | 44,788 psi | 72% | 2405 fps | 95.3% |
| Accurate 3100 | <<locked>> | 98% | 38,305 psi | 61% | 2402 fps | 95.7% |
| Accurate 4064 | <<locked>> | 80% | 39,653 psi | 64% | 2369 fps | 100% |
| Accurate 4350 | <<locked>> | 82% | 31,096 psi | 50% | 2257 fps | 95.1% |
| ADI AR 2206H | <<locked>> | 80% | 45,397 psi | 73% | 2474 fps | 99.6% |
| ADI AR 2208 | <<locked>> | 80% | 38,580 psi | 62% | 2336 fps | 98% |
| ADI Benchmark 8208 | <<locked>> | 80% | 47,485 psi | 76% | 2480 fps | 100% |
| Alliant AR-Comp | <<locked>> | 80% | 47,834 psi | 77% | 2457 fps | 100% |
| Alliant Power Pro 2000-MR | 57.2 gr | 80% | 41,307 psi | 66% | 2510 fps | 98.6% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 38,276 psi | 61% | 2359 fps | 99.2% |
| Alliant Reloder-15 | <<locked>> | 80% | 41,118 psi | 66% | 2418 fps | 98.7% |
| Alliant Reloder-16 | <<locked>> | 82% | 31,705 psi | 51% | 2274 fps | 95.2% |
| Alliant Reloder-17 | 56.3 gr | 80% | 32,982 psi | 53% | 2333 fps | 97.6% |
| Alliant Reloder-23 | <<locked>> | 90% | 29,008 psi | 47% | 2234 fps | 95.7% |
| Alliant Reloder-26 | <<locked>> | 94% | 35,679 psi | 57% | 2457 fps | 96.1% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 44,411 psi | 71% | 2477 fps | 98.8% |
| Bofors RP3 | <<locked>> | 80% | 37,811 psi | 61% | 2362 fps | 99.2% |
| Bofors RP7 | <<locked>> | 88% | 43,918 psi | 70% | 2431 fps | 95.4% |
| Hodgdon Benchmark | <<locked>> | 80% | 48,994 psi | 79% | 2464 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 46,369 psi | 74% | 2503 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 80% | 51,126 psi | 82% | 2638 fps | 99.8% |
| Hodgdon H322 | <<locked>> | 80% | 50,415 psi | 81% | 2507 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 38,653 psi | 62% | 2365 fps | 97% |
| Hodgdon H414 | <<locked>> | 86% | 41,684 psi | 67% | 2474 fps | 95.6% |
| Hodgdon H4350 | <<locked>> | 92% | 46,151 psi | 74% | 2507 fps | 95.2% |
| Hodgdon H4895 | <<locked>> | 80% | 45,861 psi | 74% | 2487 fps | 99.8% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 27,253 psi | 44% | 2133 fps | 95.2% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 39,262 psi | 63% | 2415 fps | 99.4% |
| Hodgdon Superformance | 66.9 gr | 90% | 43,250 psi | 69% | 2526 fps | 95.4% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,571 psi | 43% | 1407 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 40,683 psi | 65% | 2382 fps | 99.3% |
| IMR 3031 | <<locked>> | 80% | 41,872 psi | 67% | 2415 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 37,884 psi | 61% | 2316 fps | 98.1% |
| IMR 4166 Enduron | <<locked>> | 84% | 42,366 psi | 68% | 2375 fps | 95.6% |
| IMR 4350 | <<locked>> | 92% | 44,135 psi | 71% | 2461 fps | 95.5% |
| IMR 4451 Enduron | <<locked>> | 86% | 42,975 psi | 69% | 2415 fps | 95.7% |
| IMR 4831 | <<locked>> | 86% | 31,125 psi | 50% | 2244 fps | 95.1% |
| IMR 4895 | <<locked>> | 80% | 42,134 psi | 68% | 2448 fps | 99.3% |
| IMR 8208 XBR | <<locked>> | 80% | 47,485 psi | 76% | 2480 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 44,541 psi | 71% | 2454 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 45,281 psi | 73% | 2415 fps | 99.6% |
| Lovex S062 | <<locked>> | 80% | 40,480 psi | 65% | 2372 fps | 99.6% |
| Lovex S065 | <<locked>> | 82% | 35,375 psi | 57% | 2274 fps | 95% |
| Lovex S070 | <<locked>> | 88% | 40,364 psi | 65% | 2395 fps | 95.4% |
| Norma 201 | <<locked>> | 80% | 44,454 psi | 71% | 2428 fps | 99.9% |
| Norma 202 | <<locked>> | 80% | 44,759 psi | 72% | 2434 fps | 100% |
| Norma 203B | <<locked>> | 80% | 40,509 psi | 65% | 2408 fps | 99% |
| Norma 204 | <<locked>> | 96% | 50,082 psi | 80% | 2595 fps | 95.6% |
| Norma MRP | <<locked>> | 98% | 41,133 psi | 66% | 2536 fps | 95% |
| Norma URP | <<locked>> | 82% | 31,560 psi | 51% | 2260 fps | 95% |
| Ramshot Big Game | <<locked>> | 80% | 39,972 psi | 64% | 2421 fps | 98.8% |
| Ramshot Hunter | <<locked>> | 88% | 37,333 psi | 60% | 2395 fps | 95.1% |
| Ramshot TAC | <<locked>> | 80% | 47,326 psi | 76% | 2490 fps | 98.3% |
| Ramshot Wild Boar | <<locked>> | 80% | 46,746 psi | 75% | 2507 fps | 99.7% |
| Ramshot X-Terminator | <<locked>> | 80% | 51,082 psi | 82% | 2526 fps | 99.9% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,832 psi | 43% | 1440 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 39,044 psi | 63% | 2349 fps | 95.4% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 43,221 psi | 69% | 2513 fps | 99% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 35,114 psi | 56% | 2395 fps | 99.8% |
| ReloadSwiss RS 62 | <<locked>> | 84% | 32,982 psi | 53% | 2323 fps | 95.4% |
| ReloadSwiss RS 70 | <<locked>> | 86% | 35,389 psi | 57% | 2379 fps | 95.3% |
| Rottweil R 901 | <<locked>> | 80% | 48,501 psi | 78% | 2461 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 42,235 psi | 68% | 2382 fps | 99.8% |
| Rottweil R 903 | <<locked>> | 80% | 35,752 psi | 57% | 2313 fps | 98.6% |
| Rottweil R 907 | <<locked>> | 88% | 43,918 psi | 70% | 2431 fps | 95.4% |
| Shooters World Long Rifle | <<locked>> | 82% | 35,375 psi | 57% | 2274 fps | 95% |
| Shooters World Match Rifle | <<locked>> | 80% | 44,541 psi | 71% | 2454 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 40,480 psi | 65% | 2372 fps | 99.6% |
| Shooters World SW4350 | <<locked>> | 88% | 40,364 psi | 65% | 2395 fps | 95.4% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 36,550 psi | 59% | 2359 fps | 98.1% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 45,687 psi | 73% | 2467 fps | 98.4% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 43,787 psi | 70% | 2448 fps | 99.4% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 45,643 psi | 73% | 2379 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 38,029 psi | 61% | 2260 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 88% | 41,858 psi | 67% | 2365 fps | 95.6% |
| Somchem S321 | <<locked>> | 80% | 51,155 psi | 82% | 2549 fps | 100% |
| Somchem S335 | <<locked>> | 80% | 45,339 psi | 73% | 2382 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 45,194 psi | 72% | 2461 fps | 99.5% |
| Somchem S355 | <<locked>> | 80% | 36,535 psi | 59% | 2316 fps | 98.5% |
| Somchem S365 | <<locked>> | 80% | 26,571 psi | 43% | 2169 fps | 96.5% |
| Somchem S385 | <<locked>> | 98% | 44,164 psi | 71% | 2500 fps | 95.5% |
| Unknown powder | <<locked>> | 82% | 34,330 psi | 55% | 2313 fps | 95.3% |
| Vihtavuori N130 | <<locked>> | 80% | 51,459 psi | 83% | 2428 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 46,006 psi | 74% | 2372 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 41,785 psi | 67% | 2362 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 42,409 psi | 68% | 2375 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 34,737 psi | 56% | 2260 fps | 99.1% |
| Vihtavuori N160 | <<locked>> | 82% | 32,953 psi | 53% | 2264 fps | 95.5% |
| Vihtavuori N530 | <<locked>> | 80% | 47,413 psi | 76% | 2474 fps | 100% |
| Vihtavuori N540 | <<locked>> | 80% | 40,727 psi | 65% | 2365 fps | 100% |
| Vihtavuori N550 | <<locked>> | 82% | 32,401 psi | 52% | 2264 fps | 95.1% |
| Vihtavuori N555 | <<locked>> | 88% | 29,312 psi | 47% | 2257 fps | 95% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 30,661 psi | 49% | 2192 fps | 96.9% |
| Winchester 748 | <<locked>> | 80% | 50,821 psi | 81% | 2572 fps | 100% |
| Winchester 760 | <<locked>> | 86% | 41,684 psi | 67% | 2474 fps | 95.6% |
| Winchester StaBALL HD | <<locked>> | 92% | 27,311 psi | 44% | 2251 fps | 95% |
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 99 powders for .338 Win Mag. loaded with the .338 | 230gr | Nosler CT FailSafe. Alliant Reloder-17 delivers the highest muzzle velocity at 2,756 fps; across all powders the maximum-charge window runs from 1,575 fps to 2,756 fps. Accurate 3100 gives the best case fill at 100 %, and 99 of the 99 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (430 MPa), the top charges use 57–90 %, leaving at least 10 % headroom. The 230.0 gr projectile in 0.338" calls for a 1:14.5 twist; slower twists will usually not stabilise this weight. Accurate 3100, Alliant Reloder-16, Alliant Reloder-23 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. Alliant Power Pro 2000-MR, Hodgdon Superformance, Alliant Reloder-17 rank at the top here: for .338 Win Mag. with the .338 | 230gr | Nosler CT FailSafe 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.