Load Specifications
Bullet:.338 | 250gr | Swift A-Frame
Bullet Manufacturer:Swift
Bullet Weight:250 gr
Bullet Diameter:0.338"
Bullet Length:<<locked>>
Caliber:.338 Win Mag. load data
Case Length (l3):2.5"
Cartridge Length (C.O.L.):<<locked>>
Case Capacity:86 Grains of Water
Primer Size:Large Rifle (LR)
Barrel Length:24"
Max. allowed Pressure:62,366 psi
Recommended Twist Rate:1:15.5
Load data in caliber .338 Win Mag. with .338 | 250gr | Swift A-Frame bullet and 106 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-17 and ReloadSwiss RS 60.
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.
A valid access license is required to use the Personalized Load Calculator.
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>> | 82% | 56,231 psi | 90% | 2418 fps | 100% |
| Accurate 2495 | <<locked>> | 86% | 55,288 psi | 89% | 2448 fps | 100% |
| Accurate 2700 | <<locked>> | 86% | 53,679 psi | 86% | 2461 fps | 98.3% |
| Accurate 3100ᴾ | <<locked>> | 100% | 45,687 psi | 73% | 2441 fps | 98.5% |
| Accurate 4064 | <<locked>> | 88% | 55,593 psi | 89% | 2497 fps | 100% |
| Accurate 4350 | <<locked>> | 96% | 55,419 psi | 89% | 2589 fps | 100% |
| ADI AR 2206H | <<locked>> | 84% | 55,114 psi | 88% | 2523 fps | 100% |
| ADI AR 2208 | <<locked>> | 90% | 56,188 psi | 90% | 2526 fps | 100% |
| ADI AR 2209ᴾ | <<locked>> | 100% | 53,127 psi | 85% | 2572 fps | 97.5% |
| ADI Benchmark 8208 | <<locked>> | 82% | 54,157 psi | 87% | 2474 fps | 100% |
| Alliant AR-Comp | <<locked>> | 82% | 55,593 psi | 89% | 2444 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 86% | 54,969 psi | 88% | 2638 fps | 100% |
| Alliant Power Pro Varmintᴾ | <<locked>> | 100% | 52,982 psi | 85% | 2572 fps | 97.6% |
| Alliant Reloder- TS 15.5 | <<locked>> | 88% | 53,258 psi | 85% | 2503 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 86% | 53,621 psi | 86% | 2523 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 98% | 56,275 psi | 90% | 2638 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 92% | 53,809 psi | 86% | 2618 fps | 100% |
| Alliant Reloder-19ᴾ | <<locked>> | 100% | 52,199 psi | 84% | 2562 fps | 97.5% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 45,774 psi | 73% | 2507 fps | 96.3% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 43,163 psi | 69% | 2464 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 37,942 psi | 61% | 2379 fps | 97.3% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 48,660 psi | 78% | 2625 fps | 99.9% |
| Baschieri & Pellagri 107 | <<locked>> | 84% | 55,027 psi | 88% | 2543 fps | 100% |
| Bofors RP3 | <<locked>> | 88% | 53,766 psi | 86% | 2516 fps | 100% |
| Bofors RP5ᴾ | <<locked>> | 100% | 45,774 psi | 73% | 2507 fps | 96.3% |
| Bofors RP7 | <<locked>> | 92% | 53,577 psi | 86% | 2500 fps | 98.5% |
| Hodgdon Benchmark | <<locked>> | 82% | 55,535 psi | 89% | 2454 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 82% | 53,519 psi | 86% | 2503 fps | 100% |
| Hodgdon H380 | <<locked>> | 88% | 54,578 psi | 88% | 2533 fps | 99.9% |
| Hodgdon H414 | <<locked>> | 94% | 54,360 psi | 87% | 2589 fps | 99.1% |
| Hodgdon H4350 | <<locked>> | 92% | 54,679 psi | 88% | 2549 fps | 98.1% |
| Hodgdon H4895 | <<locked>> | 84% | 55,738 psi | 89% | 2530 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 56,376 psi | 90% | 2566 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 86% | 55,535 psi | 89% | 2566 fps | 100% |
| Hodgdon Superformance | <<locked>> | 94% | 54,563 psi | 87% | 2625 fps | 98.9% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,042 psi | 58% | 1522 fps | 100% |
| Hodgdon VARGET | <<locked>> | 84% | 53,592 psi | 86% | 2490 fps | 100% |
| IMR 3031 | <<locked>> | 84% | 56,173 psi | 90% | 2507 fps | 100% |
| IMR 4064 | <<locked>> | 88% | 55,782 psi | 89% | 2510 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 86% | 55,448 psi | 89% | 2497 fps | 99.1% |
| IMR 4350 | <<locked>> | 96% | 53,896 psi | 86% | 2523 fps | 98.6% |
| IMR 4451 Enduron | <<locked>> | 92% | 55,303 psi | 89% | 2523 fps | 99% |
| IMR 4831 | <<locked>> | 98% | 55,767 psi | 89% | 2579 fps | 100% |
| IMR 4895 | <<locked>> | 86% | 55,013 psi | 88% | 2546 fps | 100% |
| IMR 4955 Enduronᴾ | <<locked>> | 100% | 52,924 psi | 85% | 2510 fps | 95.7% |
| IMR 8208 XBR | <<locked>> | 82% | 54,157 psi | 87% | 2474 fps | 100% |
| Lovex D073.6 | <<locked>> | 84% | 55,317 psi | 89% | 2500 fps | 100% |
| Lovex S060 | <<locked>> | 84% | 54,520 psi | 87% | 2454 fps | 100% |
| Lovex S062 | <<locked>> | 88% | 55,666 psi | 89% | 2503 fps | 100% |
| Lovex S065 | <<locked>> | 94% | 54,868 psi | 88% | 2520 fps | 99.7% |
| Lovex S070 | <<locked>> | 96% | 56,043 psi | 90% | 2556 fps | 99.3% |
| Lovex S071ᴾ | <<locked>> | 100% | 38,043 psi | 61% | 2306 fps | 96.8% |
| Norma 201 | <<locked>> | 84% | 54,027 psi | 87% | 2474 fps | 100% |
| Norma 202 | <<locked>> | 84% | 54,592 psi | 88% | 2470 fps | 100% |
| Norma 203B | <<locked>> | 88% | 56,405 psi | 90% | 2556 fps | 100% |
| Norma 204 | <<locked>> | 96% | 54,476 psi | 87% | 2572 fps | 97.7% |
| Norma MRPᴾ | <<locked>> | 100% | 48,428 psi | 78% | 2585 fps | 98.3% |
| Norma URP | <<locked>> | 96% | 54,317 psi | 87% | 2575 fps | 100% |
| Ramshot Big Game | <<locked>> | 86% | 53,258 psi | 85% | 2533 fps | 100% |
| Ramshot Hunter | <<locked>> | 96% | 52,924 psi | 85% | 2575 fps | 99.4% |
| Ramshot TAC | <<locked>> | 82% | 54,012 psi | 87% | 2497 fps | 99.7% |
| Ramshot Wild Boar | <<locked>> | 82% | 53,969 psi | 87% | 2513 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,521 psi | 59% | 1558 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 88% | 54,650 psi | 88% | 2516 fps | 99.4% |
| ReloadSwiss RS 52 | <<locked>> | 84% | 54,186 psi | 87% | 2582 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 90% | 53,592 psi | 86% | 2612 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 96% | 54,984 psi | 88% | 2612 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 96% | 53,954 psi | 87% | 2635 fps | 99.9% |
| Rottweil R 901 | <<locked>> | 82% | 55,071 psi | 88% | 2451 fps | 100% |
| Rottweil R 902 | <<locked>> | 86% | 54,592 psi | 88% | 2470 fps | 100% |
| Rottweil R 903 | <<locked>> | 90% | 53,592 psi | 86% | 2510 fps | 100% |
| Rottweil R 904ᴾ | <<locked>> | 100% | 54,940 psi | 88% | 2546 fps | 96.7% |
| Rottweil R 905ᴾ | <<locked>> | 100% | 51,155 psi | 82% | 2549 fps | 97.5% |
| Rottweil R 907 | <<locked>> | 92% | 53,577 psi | 86% | 2500 fps | 98.5% |
| Shooters World Long Rifle | <<locked>> | 94% | 54,868 psi | 88% | 2520 fps | 99.7% |
| Shooters World Match Rifle | <<locked>> | 84% | 55,317 psi | 89% | 2500 fps | 100% |
| Shooters World Precision | <<locked>> | 88% | 55,666 psi | 89% | 2503 fps | 100% |
| Shooters World SW4350 | <<locked>> | 96% | 56,043 psi | 90% | 2556 fps | 99.3% |
| SNPE Vectan SP 11 | <<locked>> | 90% | 55,259 psi | 89% | 2566 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 84% | 56,405 psi | 90% | 2530 fps | 99.9% |
| SNPE Vectan SP 9 | <<locked>> | 84% | 53,606 psi | 86% | 2500 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 84% | 55,143 psi | 88% | 2408 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 90% | 55,695 psi | 89% | 2411 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 94% | 55,056 psi | 88% | 2480 fps | 99% |
| SNPE Vectan Tubal 8000ᴾ | <<locked>> | 100% | 50,662 psi | 81% | 2543 fps | 97.4% |
| Somchem S335 | <<locked>> | 84% | 54,737 psi | 88% | 2411 fps | 100% |
| Somchem S341 | <<locked>> | 84% | 56,057 psi | 90% | 2516 fps | 100% |
| Somchem S355 | <<locked>> | 90% | 53,998 psi | 87% | 2510 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 56,173 psi | 90% | 2618 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 51,750 psi | 83% | 2526 fps | 98.2% |
| Vihtavuori N133 | <<locked>> | 84% | 55,550 psi | 89% | 2392 fps | 100% |
| Vihtavuori N135 | <<locked>> | 86% | 54,578 psi | 88% | 2434 fps | 100% |
| Vihtavuori N140 | <<locked>> | 86% | 55,187 psi | 88% | 2451 fps | 100% |
| Vihtavuori N150 | <<locked>> | 92% | 55,288 psi | 89% | 2487 fps | 100% |
| Vihtavuori N160 | <<locked>> | 94% | 53,084 psi | 85% | 2523 fps | 99.9% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 44,701 psi | 72% | 2408 fps | 96.4% |
| Vihtavuori N530 | <<locked>> | 82% | 54,549 psi | 87% | 2474 fps | 100% |
| Vihtavuori N540 | <<locked>> | 86% | 53,301 psi | 85% | 2454 fps | 100% |
| Vihtavuori N550 | <<locked>> | 96% | 55,651 psi | 89% | 2579 fps | 100% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 48,138 psi | 77% | 2530 fps | 100% |
| Winchester 6.5 StaBALL | <<locked>> | 96% | 56,391 psi | 90% | 2546 fps | 100% |
| Winchester 748 | <<locked>> | 82% | 54,766 psi | 88% | 2520 fps | 100% |
| Winchester 760 | <<locked>> | 94% | 54,621 psi | 88% | 2592 fps | 99.1% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 38,754 psi | 62% | 2493 fps | 100% |
| Winchester StaBALL Match | <<locked>> | 84% | 53,432 psi | 86% | 2507 fps | 100% |
| Winchester Supreme 780ᴾ | <<locked>> | 100% | 48,718 psi | 78% | 2474 fps | 96.6% |
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 2015 | <<locked>> | 80% | 52,910 psi | 85% | 2379 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 45,614 psi | 73% | 2323 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 44,295 psi | 71% | 2316 fps | 96.5% |
| Accurate 3100 | <<locked>> | 92% | 34,969 psi | 56% | 2247 fps | 95.8% |
| Accurate 4064 | <<locked>> | 80% | 43,134 psi | 69% | 2326 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 32,111 psi | 51% | 2195 fps | 96.7% |
| ADI AR 2206H | <<locked>> | 80% | 48,718 psi | 78% | 2431 fps | 100% |
| ADI AR 2208 | <<locked>> | 80% | 41,437 psi | 66% | 2300 fps | 99.3% |
| ADI AR 2209 | <<locked>> | 94% | 43,990 psi | 71% | 2421 fps | 95.3% |
| ADI Benchmark 8208 | <<locked>> | 80% | 50,792 psi | 81% | 2428 fps | 100% |
| Alliant AR-Comp | <<locked>> | 80% | 52,156 psi | 84% | 2405 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 44,846 psi | 72% | 2484 fps | 99.7% |
| Alliant Power Pro Varmint | <<locked>> | 94% | 43,758 psi | 70% | 2421 fps | 95.5% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 41,408 psi | 66% | 2323 fps | 99.9% |
| Alliant Reloder-15 | <<locked>> | 80% | 44,353 psi | 71% | 2382 fps | 99.7% |
| Alliant Reloder-16 | <<locked>> | 80% | 32,198 psi | 52% | 2205 fps | 96.8% |
| Alliant Reloder-17 | 57 gr | 80% | 35,940 psi | 58% | 2316 fps | 99.3% |
| Alliant Reloder-19 | <<locked>> | 94% | 43,236 psi | 69% | 2415 fps | 95.4% |
| Alliant Reloder-22 | <<locked>> | 98% | 43,076 psi | 69% | 2457 fps | 95.5% |
| Alliant Reloder-23 | <<locked>> | 84% | 26,455 psi | 42% | 2087 fps | 95.8% |
| Alliant Reloder-25 | <<locked>> | 96% | 33,591 psi | 54% | 2277 fps | 95.5% |
| Alliant Reloder-26 | <<locked>> | 88% | 31,966 psi | 51% | 2287 fps | 96% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 48,225 psi | 77% | 2448 fps | 99.8% |
| Bofors RP3 | <<locked>> | 80% | 41,365 psi | 66% | 2333 fps | 99.9% |
| Bofors RP5 | <<locked>> | 98% | 43,076 psi | 69% | 2457 fps | 95.5% |
| Bofors RP7 | <<locked>> | 82% | 39,479 psi | 63% | 2264 fps | 95.4% |
| Hodgdon Benchmark | <<locked>> | 80% | 52,373 psi | 84% | 2411 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 50,212 psi | 81% | 2461 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 41,989 psi | 67% | 2339 fps | 98.7% |
| Hodgdon H414 | <<locked>> | 82% | 36,550 psi | 59% | 2287 fps | 95.2% |
| Hodgdon H4350 | <<locked>> | 84% | 42,627 psi | 68% | 2359 fps | 95.6% |
| Hodgdon H4895 | <<locked>> | 80% | 49,255 psi | 79% | 2441 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 29,776 psi | 48% | 2119 fps | 97.6% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 45,397 psi | 73% | 2425 fps | 100% |
| Hodgdon Superformance | <<locked>> | 84% | 38,247 psi | 61% | 2346 fps | 95.1% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,861 psi | 43% | 1358 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 47,065 psi | 75% | 2395 fps | 100% |
| IMR 3031 | <<locked>> | 80% | 49,487 psi | 79% | 2421 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 43,540 psi | 70% | 2329 fps | 99.6% |
| IMR 4166 Enduron | <<locked>> | 80% | 46,021 psi | 74% | 2356 fps | 97.7% |
| IMR 4350 | <<locked>> | 86% | 39,697 psi | 64% | 2293 fps | 95.5% |
| IMR 4451 Enduron | <<locked>> | 80% | 38,464 psi | 62% | 2244 fps | 95.6% |
| IMR 4831 | <<locked>> | 80% | 31,256 psi | 50% | 2159 fps | 96.4% |
| IMR 4895 | <<locked>> | 80% | 45,484 psi | 73% | 2408 fps | 99.9% |
| IMR 4955 Enduron | <<locked>> | 98% | 49,864 psi | 80% | 2464 fps | 95% |
| IMR 8208 XBR | <<locked>> | 80% | 50,792 psi | 81% | 2428 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 48,486 psi | 78% | 2411 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 48,254 psi | 77% | 2369 fps | 100% |
| Lovex S062 | <<locked>> | 80% | 43,569 psi | 70% | 2329 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 35,882 psi | 58% | 2201 fps | 96.4% |
| Lovex S070 | <<locked>> | 82% | 36,376 psi | 58% | 2228 fps | 95.3% |
| Lovex S071 | <<locked>> | 96% | 33,446 psi | 54% | 2215 fps | 95.3% |
| Norma 201 | <<locked>> | 80% | 47,674 psi | 76% | 2382 fps | 100% |
| Norma 202 | <<locked>> | 80% | 48,153 psi | 77% | 2385 fps | 100% |
| Norma 203B | <<locked>> | 80% | 43,743 psi | 70% | 2372 fps | 99.8% |
| Norma 204 | <<locked>> | 90% | 44,614 psi | 72% | 2418 fps | 95.5% |
| Norma MRP | <<locked>> | 92% | 37,057 psi | 59% | 2369 fps | 95% |
| Norma URP | <<locked>> | 80% | 32,329 psi | 52% | 2195 fps | 96.6% |
| Ramshot Big Game | <<locked>> | 80% | 43,613 psi | 70% | 2388 fps | 99.8% |
| Ramshot Hunter | <<locked>> | 82% | 33,620 psi | 54% | 2228 fps | 95% |
| Ramshot TAC | <<locked>> | 80% | 50,734 psi | 81% | 2451 fps | 99.4% |
| Ramshot Wild Boar | <<locked>> | 80% | 50,415 psi | 81% | 2464 fps | 100% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,369 psi | 44% | 1391 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 42,192 psi | 68% | 2323 fps | 97.4% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 47,326 psi | 76% | 2480 fps | 99.9% |
| ReloadSwiss RS 60 | 57 gr | 80% | 38,247 psi | 61% | 2369 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 31,734 psi | 51% | 2208 fps | 96.2% |
| ReloadSwiss RS 70 | 57.9 gr | 80% | 31,633 psi | 51% | 2211 fps | 95.2% |
| Rottweil R 901 | <<locked>> | 80% | 51,880 psi | 83% | 2408 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 45,556 psi | 73% | 2343 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 38,914 psi | 62% | 2283 fps | 99.7% |
| Rottweil R 904 | <<locked>> | 96% | 48,617 psi | 78% | 2451 fps | 95.4% |
| Rottweil R 905 | <<locked>> | 94% | 41,916 psi | 67% | 2398 fps | 95.3% |
| Rottweil R 907 | <<locked>> | 82% | 39,479 psi | 63% | 2264 fps | 95.4% |
| Shooters World Long Rifle | <<locked>> | 80% | 35,882 psi | 58% | 2201 fps | 96.4% |
| Shooters World Match Rifle | <<locked>> | 80% | 48,486 psi | 78% | 2411 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 43,569 psi | 70% | 2329 fps | 100% |
| Shooters World SW4350 | <<locked>> | 82% | 36,376 psi | 58% | 2228 fps | 95.3% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 39,900 psi | 64% | 2329 fps | 99.4% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 49,342 psi | 79% | 2431 fps | 99.6% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 47,195 psi | 76% | 2408 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 48,965 psi | 79% | 2329 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 41,060 psi | 66% | 2218 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 82% | 37,449 psi | 60% | 2198 fps | 95.5% |
| SNPE Vectan Tubal 8000 | <<locked>> | 94% | 41,553 psi | 67% | 2392 fps | 95.1% |
| Somchem S335 | <<locked>> | 80% | 48,457 psi | 78% | 2329 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 49,066 psi | 79% | 2425 fps | 100% |
| Somchem S355 | <<locked>> | 80% | 39,523 psi | 63% | 2283 fps | 99.6% |
| Somchem S365 | <<locked>> | 80% | 29,008 psi | 47% | 2156 fps | 98.7% |
| Somchem S385 | <<locked>> | 92% | 39,929 psi | 64% | 2336 fps | 95.6% |
| Vihtavuori N133 | <<locked>> | 80% | 49,414 psi | 79% | 2316 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 45,469 psi | 73% | 2316 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 45,658 psi | 73% | 2326 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 37,637 psi | 60% | 2228 fps | 99.9% |
| Vihtavuori N160 | <<locked>> | 80% | 33,692 psi | 54% | 2195 fps | 97% |
| Vihtavuori N165 | <<locked>> | 98% | 41,829 psi | 67% | 2359 fps | 95.6% |
| Vihtavuori N530 | <<locked>> | 80% | 51,053 psi | 82% | 2428 fps | 100% |
| Vihtavuori N540 | <<locked>> | 80% | 44,019 psi | 71% | 2323 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 33,214 psi | 53% | 2198 fps | 96.6% |
| Vihtavuori N555 | <<locked>> | 82% | 26,760 psi | 43% | 2103 fps | 95% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 33,286 psi | 53% | 2175 fps | 98.8% |
| Winchester 748 | <<locked>> | 80% | 51,285 psi | 82% | 2474 fps | 100% |
| Winchester 760 | <<locked>> | 82% | 36,738 psi | 59% | 2290 fps | 95.3% |
| Winchester StaBALL HD | <<locked>> | 86% | 24,787 psi | 40% | 2100 fps | 95.1% |
| Winchester StaBALL Match | <<locked>> | 80% | 46,963 psi | 75% | 2415 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 98% | 45,484 psi | 73% | 2421 fps | 95.8% |
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 106 powders for .338 Win Mag. loaded with the .338 | 250gr | Swift A-Frame. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 2,638 fps; across all powders the maximum-charge window runs from 1,522 fps to 2,638 fps. Accurate 3100 gives the best case fill at 100 %, and 106 of the 106 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (430 MPa), the top charges use 58–90 %, leaving at least 10 % headroom. The 250.0 gr projectile in 0.338" calls for a 1:15.5 twist; slower twists will usually not stabilise this weight. Accurate 3100, ADI AR 2209, Alliant Power Pro Varmint 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-17, ReloadSwiss RS 60 rank at the top here: for .338 Win Mag. with the .338 | 250gr | Swift A-Frame 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.