Load Specifications
Bullet:.338 | 250gr | Barnes MRX BT
Bullet Manufacturer:Barnes
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:1:14.0
Load data in caliber .338 Win Mag. with .338 | 250gr | Barnes MRX BT bullet and 104 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Alliant Reloder-17, ReloadSwiss RS 60 and ReloadSwiss RS 70.
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% | 53,185 psi | 85% | 2379 fps | 100% |
| Accurate 2495 | <<locked>> | 88% | 55,230 psi | 89% | 2444 fps | 100% |
| Accurate 2520 | <<locked>> | 82% | 53,476 psi | 86% | 2464 fps | 100% |
| Accurate 2700 | <<locked>> | 88% | 54,418 psi | 87% | 2464 fps | 98.2% |
| Accurate 3100ᴾ | <<locked>> | 100% | 42,221 psi | 68% | 2379 fps | 97.7% |
| Accurate 4064 | <<locked>> | 90% | 55,390 psi | 89% | 2493 fps | 100% |
| Accurate 4350 | <<locked>> | 98% | 55,434 psi | 89% | 2582 fps | 100% |
| ADI AR 2206H | <<locked>> | 86% | 55,883 psi | 90% | 2526 fps | 100% |
| ADI AR 2208 | <<locked>> | 90% | 53,577 psi | 86% | 2484 fps | 100% |
| ADI AR 2209ᴾ | <<locked>> | 100% | 50,473 psi | 81% | 2520 fps | 96.7% |
| ADI Benchmark 8208 | <<locked>> | 84% | 54,882 psi | 88% | 2477 fps | 100% |
| Alliant AR-Comp | <<locked>> | 84% | 56,072 psi | 90% | 2448 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 88% | 55,782 psi | 89% | 2641 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 90% | 53,679 psi | 86% | 2503 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 88% | 54,027 psi | 87% | 2523 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 98% | 53,200 psi | 85% | 2589 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 94% | 54,375 psi | 87% | 2618 fps | 100% |
| Alliant Reloder-19ᴾ | <<locked>> | 100% | 49,240 psi | 79% | 2510 fps | 96.7% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 40,422 psi | 65% | 2408 fps | 99.8% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 35,621 psi | 57% | 2320 fps | 96.2% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 45,121 psi | 72% | 2559 fps | 99.4% |
| Baschieri & Pellagri 107 | <<locked>> | 86% | 55,724 psi | 89% | 2546 fps | 100% |
| Bofors RP3 | <<locked>> | 90% | 54,056 psi | 87% | 2516 fps | 100% |
| Bofors RP7 | <<locked>> | 94% | 54,056 psi | 87% | 2497 fps | 98.4% |
| Hodgdon Benchmark | <<locked>> | 82% | 53,287 psi | 85% | 2418 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 84% | 54,172 psi | 87% | 2507 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 82% | 56,376 psi | 90% | 2598 fps | 100% |
| Hodgdon H380 | <<locked>> | 90% | 54,897 psi | 88% | 2530 fps | 99.9% |
| Hodgdon H414 | <<locked>> | 96% | 54,621 psi | 88% | 2585 fps | 99% |
| Hodgdon H4350 | <<locked>> | 94% | 55,303 psi | 89% | 2549 fps | 98% |
| Hodgdon H4895 | <<locked>> | 84% | 53,026 psi | 85% | 2487 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 53,040 psi | 85% | 2520 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 88% | 56,115 psi | 90% | 2566 fps | 100% |
| Hodgdon Superformance | <<locked>> | 96% | 55,071 psi | 88% | 2621 fps | 98.8% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,534 psi | 57% | 1503 fps | 100% |
| Hodgdon VARGET | <<locked>> | 86% | 54,186 psi | 87% | 2490 fps | 100% |
| IMR 3031 | <<locked>> | 84% | 53,098 psi | 85% | 2467 fps | 100% |
| IMR 4064 | <<locked>> | 88% | 53,026 psi | 85% | 2467 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 88% | 56,347 psi | 90% | 2500 fps | 99% |
| IMR 4350 | <<locked>> | 98% | 54,621 psi | 88% | 2526 fps | 98.5% |
| IMR 4451 Enduron | <<locked>> | 94% | 56,043 psi | 90% | 2526 fps | 98.9% |
| IMR 4831ᴾ | <<locked>> | 100% | 55,970 psi | 90% | 2575 fps | 100% |
| IMR 4895 | <<locked>> | 88% | 55,419 psi | 89% | 2546 fps | 100% |
| IMR 8208 XBR | <<locked>> | 84% | 54,882 psi | 88% | 2477 fps | 100% |
| Lovex D073.6 | <<locked>> | 86% | 55,564 psi | 89% | 2500 fps | 100% |
| Lovex S060 | <<locked>> | 86% | 55,434 psi | 89% | 2461 fps | 100% |
| Lovex S062 | <<locked>> | 90% | 56,115 psi | 90% | 2503 fps | 100% |
| Lovex S065 | <<locked>> | 96% | 55,303 psi | 89% | 2516 fps | 99.6% |
| Lovex S070 | <<locked>> | 98% | 56,333 psi | 90% | 2552 fps | 99.2% |
| Norma 201 | <<locked>> | 86% | 54,520 psi | 87% | 2474 fps | 100% |
| Norma 202 | <<locked>> | 86% | 55,216 psi | 89% | 2470 fps | 100% |
| Norma 203B | <<locked>> | 88% | 53,243 psi | 85% | 2510 fps | 100% |
| Norma 204 | <<locked>> | 98% | 55,114 psi | 88% | 2572 fps | 97.5% |
| Norma MRPᴾ | <<locked>> | 100% | 45,266 psi | 73% | 2523 fps | 97.4% |
| Norma URP | <<locked>> | 98% | 54,534 psi | 87% | 2572 fps | 100% |
| Ramshot Big Game | <<locked>> | 88% | 53,853 psi | 86% | 2536 fps | 100% |
| Ramshot Hunter | <<locked>> | 98% | 53,258 psi | 85% | 2572 fps | 99.3% |
| Ramshot TAC | <<locked>> | 84% | 54,969 psi | 88% | 2503 fps | 99.7% |
| Ramshot Wild Boar | <<locked>> | 84% | 54,810 psi | 88% | 2516 fps | 100% |
| Ramshot X-Terminator | <<locked>> | 82% | 55,535 psi | 89% | 2480 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,187 psi | 58% | 1542 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 90% | 55,187 psi | 88% | 2516 fps | 99.3% |
| ReloadSwiss RS 52 | <<locked>> | 86% | 54,839 psi | 88% | 2585 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 92% | 54,085 psi | 87% | 2615 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 98% | 55,230 psi | 89% | 2608 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 98% | 54,607 psi | 88% | 2635 fps | 99.9% |
| Rottweil R 901 | <<locked>> | 84% | 55,187 psi | 88% | 2448 fps | 100% |
| Rottweil R 902 | <<locked>> | 88% | 55,114 psi | 88% | 2474 fps | 100% |
| Rottweil R 903 | <<locked>> | 92% | 53,882 psi | 86% | 2510 fps | 100% |
| Rottweil R 904ᴾ | <<locked>> | 100% | 52,170 psi | 84% | 2497 fps | 95.9% |
| Rottweil R 905ᴾ | <<locked>> | 100% | 47,906 psi | 77% | 2490 fps | 96.6% |
| Rottweil R 907 | <<locked>> | 94% | 54,056 psi | 87% | 2497 fps | 98.4% |
| Shooters World Long Rifle | <<locked>> | 96% | 55,303 psi | 89% | 2516 fps | 99.6% |
| Shooters World Match Rifle | <<locked>> | 86% | 55,564 psi | 89% | 2500 fps | 100% |
| Shooters World Precision | <<locked>> | 90% | 56,115 psi | 90% | 2503 fps | 100% |
| Shooters World SW4350 | <<locked>> | 98% | 56,333 psi | 90% | 2552 fps | 99.2% |
| SNPE Vectan SP 11 | <<locked>> | 92% | 55,738 psi | 89% | 2566 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 84% | 53,374 psi | 86% | 2484 fps | 99.8% |
| SNPE Vectan SP 9 | <<locked>> | 86% | 54,418 psi | 87% | 2503 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 86% | 55,970 psi | 90% | 2411 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 90% | 52,982 psi | 85% | 2375 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 96% | 55,521 psi | 89% | 2477 fps | 98.9% |
| SNPE Vectan Tubal 8000ᴾ | <<locked>> | 100% | 47,456 psi | 76% | 2487 fps | 96.5% |
| Somchem S321 | <<locked>> | 82% | 56,028 psi | 90% | 2507 fps | 100% |
| Somchem S335 | <<locked>> | 86% | 55,390 psi | 89% | 2411 fps | 100% |
| Somchem S341 | <<locked>> | 84% | 53,142 psi | 85% | 2474 fps | 100% |
| Somchem S355 | <<locked>> | 92% | 54,157 psi | 87% | 2507 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 52,663 psi | 84% | 2575 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 48,515 psi | 78% | 2474 fps | 97.5% |
| Vihtavuori N130 | <<locked>> | 82% | 55,927 psi | 90% | 2375 fps | 100% |
| Vihtavuori N133 | <<locked>> | 86% | 56,318 psi | 90% | 2395 fps | 100% |
| Vihtavuori N135 | <<locked>> | 88% | 55,027 psi | 88% | 2434 fps | 100% |
| Vihtavuori N140 | <<locked>> | 88% | 55,738 psi | 89% | 2454 fps | 100% |
| Vihtavuori N150 | <<locked>> | 94% | 55,695 psi | 89% | 2487 fps | 100% |
| Vihtavuori N160 | <<locked>> | 96% | 53,548 psi | 86% | 2523 fps | 99.9% |
| Vihtavuori N530 | <<locked>> | 84% | 55,347 psi | 89% | 2477 fps | 100% |
| Vihtavuori N540 | <<locked>> | 88% | 53,824 psi | 86% | 2454 fps | 100% |
| Vihtavuori N550 | <<locked>> | 98% | 55,956 psi | 90% | 2575 fps | 100% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 44,469 psi | 71% | 2474 fps | 99.7% |
| Winchester 6.5 StaBALL | <<locked>> | 96% | 53,534 psi | 86% | 2503 fps | 100% |
| Winchester 748 | <<locked>> | 84% | 55,535 psi | 89% | 2523 fps | 100% |
| Winchester 760 | <<locked>> | 96% | 54,897 psi | 88% | 2589 fps | 99% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 36,071 psi | 58% | 2428 fps | 99.9% |
| Winchester StaBALL Match | <<locked>> | 86% | 54,201 psi | 87% | 2510 fps | 100% |
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% | 50,096 psi | 80% | 2339 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 42,293 psi | 68% | 2277 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 49,908 psi | 80% | 2418 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 41,989 psi | 67% | 2270 fps | 95.6% |
| Accurate 3100 | <<locked>> | 94% | 34,301 psi | 55% | 2234 fps | 95.4% |
| Accurate 4064 | <<locked>> | 80% | 40,074 psi | 64% | 2280 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 29,501 psi | 47% | 2136 fps | 95.5% |
| ADI AR 2206H | <<locked>> | 80% | 46,296 psi | 74% | 2388 fps | 99.9% |
| ADI AR 2208 | <<locked>> | 80% | 39,262 psi | 63% | 2257 fps | 98.8% |
| ADI AR 2209 | <<locked>> | 96% | 44,164 psi | 71% | 2418 fps | 95.1% |
| ADI Benchmark 8208 | <<locked>> | 80% | 48,443 psi | 78% | 2392 fps | 100% |
| Alliant AR-Comp | <<locked>> | 80% | 49,226 psi | 79% | 2369 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 42,221 psi | 68% | 2431 fps | 99.4% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 38,986 psi | 63% | 2277 fps | 99.7% |
| Alliant Reloder-15 | <<locked>> | 80% | 41,916 psi | 67% | 2336 fps | 99.3% |
| Alliant Reloder-16 | <<locked>> | 80% | 30,226 psi | 48% | 2152 fps | 95.7% |
| Alliant Reloder-17 | 55.1 gr | 80% | 33,533 psi | 54% | 2260 fps | 98.7% |
| Alliant Reloder-19 | <<locked>> | 96% | 43,439 psi | 70% | 2411 fps | 95.1% |
| Alliant Reloder-23 | <<locked>> | 86% | 26,078 psi | 42% | 2073 fps | 95.3% |
| Alliant Reloder-25 | <<locked>> | 98% | 33,475 psi | 54% | 2270 fps | 95.2% |
| Alliant Reloder-26 | <<locked>> | 90% | 31,734 psi | 51% | 2277 fps | 95.6% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 45,614 psi | 73% | 2398 fps | 99.5% |
| Bofors RP3 | <<locked>> | 80% | 38,464 psi | 62% | 2280 fps | 99.7% |
| Bofors RP7 | <<locked>> | 84% | 39,566 psi | 63% | 2260 fps | 95.2% |
| Hodgdon Benchmark | <<locked>> | 80% | 50,096 psi | 80% | 2375 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 47,311 psi | 76% | 2415 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 80% | 52,591 psi | 84% | 2549 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 39,392 psi | 63% | 2287 fps | 98% |
| Hodgdon H414 | <<locked>> | 84% | 36,535 psi | 59% | 2283 fps | 95% |
| Hodgdon H4350 | <<locked>> | 86% | 42,786 psi | 69% | 2356 fps | 95.4% |
| Hodgdon H4895 | <<locked>> | 80% | 46,760 psi | 75% | 2398 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 27,673 psi | 44% | 2064 fps | 96.5% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 42,772 psi | 69% | 2379 fps | 100% |
| Hodgdon Superformance | <<locked>> | 86% | 38,624 psi | 62% | 2346 fps | 95% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,484 psi | 42% | 1342 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 44,817 psi | 72% | 2356 fps | 99.9% |
| IMR 3031 | <<locked>> | 80% | 46,688 psi | 75% | 2382 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 41,249 psi | 66% | 2287 fps | 99.3% |
| IMR 4166 Enduron | <<locked>> | 80% | 43,772 psi | 70% | 2310 fps | 96.9% |
| IMR 4350 | <<locked>> | 88% | 39,784 psi | 64% | 2290 fps | 95.3% |
| IMR 4451 Enduron | <<locked>> | 82% | 38,653 psi | 62% | 2244 fps | 95.4% |
| IMR 4831 | <<locked>> | 80% | 28,805 psi | 46% | 2100 fps | 95.2% |
| IMR 4895 | <<locked>> | 80% | 42,975 psi | 69% | 2362 fps | 99.7% |
| IMR 8208 XBR | <<locked>> | 80% | 48,443 psi | 78% | 2392 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 45,513 psi | 73% | 2365 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 46,050 psi | 74% | 2326 fps | 99.9% |
| Lovex S062 | <<locked>> | 80% | 41,046 psi | 66% | 2287 fps | 99.9% |
| Lovex S065 | <<locked>> | 80% | 33,634 psi | 54% | 2149 fps | 95.4% |
| Lovex S070 | <<locked>> | 84% | 36,230 psi | 58% | 2224 fps | 95.1% |
| Norma 201 | <<locked>> | 80% | 45,063 psi | 72% | 2339 fps | 100% |
| Norma 202 | <<locked>> | 80% | 45,600 psi | 73% | 2343 fps | 100% |
| Norma 203B | <<locked>> | 80% | 41,263 psi | 66% | 2326 fps | 99.5% |
| Norma 204 | <<locked>> | 92% | 44,904 psi | 72% | 2415 fps | 95.3% |
| Norma MRP | <<locked>> | 96% | 39,392 psi | 63% | 2411 fps | 95.6% |
| Norma URP | <<locked>> | 80% | 30,110 psi | 48% | 2139 fps | 95.5% |
| Ramshot Big Game | <<locked>> | 80% | 40,930 psi | 66% | 2339 fps | 99.4% |
| Ramshot Hunter | <<locked>> | 86% | 35,897 psi | 58% | 2277 fps | 95.7% |
| Ramshot TAC | <<locked>> | 80% | 48,254 psi | 77% | 2408 fps | 99% |
| Ramshot Wild Boar | <<locked>> | 80% | 47,964 psi | 77% | 2421 fps | 100% |
| Ramshot X-Terminator | <<locked>> | 80% | 52,054 psi | 83% | 2434 fps | 100% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,934 psi | 43% | 1378 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 39,856 psi | 64% | 2277 fps | 96.6% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 44,454 psi | 71% | 2431 fps | 99.6% |
| ReloadSwiss RS 60 | 55.1 gr | 80% | 35,766 psi | 57% | 2316 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 82% | 31,546 psi | 51% | 2205 fps | 95.9% |
| ReloadSwiss RS 70 | 58.8 gr | 84% | 33,808 psi | 54% | 2260 fps | 95.9% |
| Rottweil R 901 | <<locked>> | 80% | 48,936 psi | 78% | 2365 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 42,975 psi | 69% | 2300 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 36,274 psi | 58% | 2234 fps | 99.2% |
| Rottweil R 904 | <<locked>> | 98% | 48,892 psi | 78% | 2448 fps | 95.1% |
| Rottweil R 905 | <<locked>> | 96% | 41,974 psi | 67% | 2392 fps | 95% |
| Rottweil R 907 | <<locked>> | 84% | 39,566 psi | 63% | 2260 fps | 95.2% |
| Shooters World Long Rifle | <<locked>> | 80% | 33,634 psi | 54% | 2149 fps | 95.4% |
| Shooters World Match Rifle | <<locked>> | 80% | 45,513 psi | 73% | 2365 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 41,046 psi | 66% | 2287 fps | 99.9% |
| Shooters World SW4350 | <<locked>> | 84% | 36,230 psi | 58% | 2224 fps | 95.1% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 37,449 psi | 60% | 2283 fps | 98.9% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 46,514 psi | 75% | 2382 fps | 99.1% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 44,759 psi | 72% | 2365 fps | 99.8% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 46,514 psi | 75% | 2290 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 38,783 psi | 62% | 2175 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 84% | 37,478 psi | 60% | 2195 fps | 95.2% |
| SNPE Vectan Tubal 8000 | <<locked>> | 98% | 44,396 psi | 71% | 2438 fps | 95.7% |
| Somchem S321 | <<locked>> | 80% | 52,417 psi | 84% | 2461 fps | 100% |
| Somchem S335 | <<locked>> | 80% | 46,035 psi | 74% | 2290 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 46,441 psi | 74% | 2379 fps | 99.9% |
| Somchem S355 | <<locked>> | 80% | 37,043 psi | 59% | 2238 fps | 99.2% |
| Somchem S365 | <<locked>> | 80% | 26,890 psi | 43% | 2100 fps | 97.7% |
| Somchem S385 | <<locked>> | 94% | 39,697 psi | 64% | 2326 fps | 95.3% |
| Vihtavuori N130 | <<locked>> | 80% | 52,504 psi | 84% | 2336 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 46,978 psi | 75% | 2280 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 42,656 psi | 68% | 2274 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 43,236 psi | 69% | 2287 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 35,317 psi | 57% | 2182 fps | 99.6% |
| Vihtavuori N160 | <<locked>> | 80% | 31,488 psi | 50% | 2146 fps | 96% |
| Vihtavuori N530 | <<locked>> | 80% | 48,414 psi | 78% | 2385 fps | 100% |
| Vihtavuori N540 | <<locked>> | 80% | 41,524 psi | 67% | 2280 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 30,850 psi | 49% | 2142 fps | 95.5% |
| Vihtavuori N555 | <<locked>> | 86% | 27,891 psi | 45% | 2136 fps | 95.5% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 31,212 psi | 50% | 2126 fps | 98% |
| Winchester 748 | <<locked>> | 80% | 48,370 psi | 78% | 2428 fps | 100% |
| Winchester 760 | <<locked>> | 84% | 36,738 psi | 59% | 2287 fps | 95.1% |
| Winchester StaBALL HD | <<locked>> | 90% | 25,976 psi | 42% | 2139 fps | 95.8% |
| Winchester StaBALL Match | <<locked>> | 80% | 44,208 psi | 71% | 2365 fps | 99.9% |
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 104 powders for .338 Win Mag. loaded with the .338 | 250gr | Barnes MRX BT. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 2,641 fps; across all powders the maximum-charge window runs from 1,503 fps to 2,641 fps. Accurate 3100 gives the best case fill at 100 %, and 104 of the 104 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 250.0 gr projectile in 0.338" calls for a 1:14.0 twist; slower twists will usually not stabilise this weight. Accurate 3100, ADI AR 2209, Alliant Reloder-19 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 Reloder-17, ReloadSwiss RS 60, ReloadSwiss RS 70 rank at the top here: for .338 Win Mag. with the .338 | 250gr | Barnes MRX 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.