Load Specifications
Bullet:.338 | 275gr | Speer SSP
Bullet Manufacturer:Speer
Bullet Weight:275 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:1:16.0
Load data in caliber .338 Win Mag. with .338 | 275gr | Speer SSP 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, ReloadSwiss RS 60 and Hodgdon H414.
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 2495 | <<locked>> | 84% | 55,767 psi | 89% | 2326 fps | 100% |
| Accurate 2700 | <<locked>> | 84% | 53,650 psi | 86% | 2349 fps | 99% |
| Accurate 3100ᴾ | <<locked>> | 100% | 49,937 psi | 80% | 2388 fps | 99.6% |
| Accurate 4064 | <<locked>> | 86% | 55,941 psi | 90% | 2372 fps | 100% |
| Accurate 4350 | <<locked>> | 94% | 56,362 psi | 90% | 2474 fps | 100% |
| Accurate MAGPROᴾ | <<locked>> | 100% | 51,532 psi | 83% | 2503 fps | 96.2% |
| ADI AR 2206H | <<locked>> | 82% | 55,259 psi | 89% | 2398 fps | 100% |
| ADI AR 2208 | <<locked>> | 88% | 56,304 psi | 90% | 2405 fps | 100% |
| ADI AR 2209 | <<locked>> | 98% | 53,621 psi | 86% | 2467 fps | 98.6% |
| ADI AR 2213ᴾ | <<locked>> | 100% | 51,169 psi | 82% | 2461 fps | 97% |
| Alliant Power Pro 2000-MR | <<locked>> | 84% | 55,245 psi | 89% | 2513 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 86% | 53,432 psi | 86% | 2382 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 84% | 53,737 psi | 86% | 2402 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 94% | 53,490 psi | 86% | 2477 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 90% | 54,433 psi | 87% | 2497 fps | 100% |
| Alliant Reloder-19ᴾ | <<locked>> | 100% | 56,246 psi | 90% | 2503 fps | 99% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 49,676 psi | 80% | 2461 fps | 98.2% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 46,891 psi | 75% | 2402 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 41,002 psi | 66% | 2343 fps | 99.2% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 53,243 psi | 85% | 2569 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 82% | 54,998 psi | 88% | 2421 fps | 100% |
| Bofors RP15ᴾ | <<locked>> | 100% | 45,774 psi | 73% | 2395 fps | 97.3% |
| Bofors RP3 | <<locked>> | 86% | 54,128 psi | 87% | 2398 fps | 100% |
| Bofors RP5ᴾ | <<locked>> | 100% | 49,676 psi | 80% | 2461 fps | 98.2% |
| Bofors RP7 | <<locked>> | 90% | 53,606 psi | 86% | 2385 fps | 99.2% |
| Hodgdon H380 | <<locked>> | 86% | 54,563 psi | 87% | 2411 fps | 100% |
| Hodgdon H414 | <<locked>> | 92% | 54,795 psi | 88% | 2474 fps | 99.7% |
| Hodgdon H4350 | <<locked>> | 90% | 54,984 psi | 88% | 2438 fps | 99% |
| Hodgdon H4831ᴾ | <<locked>> | 100% | 55,027 psi | 88% | 2464 fps | 97.1% |
| Hodgdon H4831 SCᴾ | <<locked>> | 100% | 53,693 psi | 86% | 2448 fps | 96.9% |
| Hodgdon H4895 | <<locked>> | 82% | 55,883 psi | 90% | 2405 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 96% | 53,650 psi | 86% | 2408 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 84% | 55,695 psi | 89% | 2441 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 40,292 psi | 65% | 2365 fps | 96.4% |
| Hodgdon Superformance | <<locked>> | 92% | 54,679 psi | 88% | 2510 fps | 99.5% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,376 psi | 58% | 1450 fps | 100% |
| Hodgdon VARGET | <<locked>> | 82% | 53,417 psi | 86% | 2365 fps | 100% |
| IMR 3031 | <<locked>> | 82% | 56,434 psi | 90% | 2379 fps | 100% |
| IMR 4064 | <<locked>> | 86% | 55,898 psi | 90% | 2388 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 84% | 55,158 psi | 88% | 2379 fps | 99.6% |
| IMR 4350 | <<locked>> | 94% | 54,273 psi | 87% | 2415 fps | 99.3% |
| IMR 4451 Enduron | <<locked>> | 90% | 55,288 psi | 89% | 2408 fps | 99.6% |
| IMR 4831 | <<locked>> | 94% | 52,953 psi | 85% | 2421 fps | 100% |
| IMR 4895 | <<locked>> | 84% | 55,085 psi | 88% | 2425 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 98% | 53,301 psi | 85% | 2408 fps | 97% |
| IMR 7828 SSCᴾ | <<locked>> | 100% | 48,718 psi | 78% | 2434 fps | 96.6% |
| Lovex D073.6 | <<locked>> | 82% | 55,564 psi | 89% | 2375 fps | 100% |
| Lovex S060 | <<locked>> | 82% | 54,317 psi | 87% | 2333 fps | 100% |
| Lovex S062 | <<locked>> | 86% | 55,941 psi | 90% | 2382 fps | 100% |
| Lovex S065 | <<locked>> | 92% | 55,317 psi | 89% | 2408 fps | 100% |
| Lovex S070 | <<locked>> | 92% | 52,968 psi | 85% | 2398 fps | 99.5% |
| Lovex S071ᴾ | <<locked>> | 100% | 41,553 psi | 67% | 2260 fps | 98.6% |
| Norma 201 | <<locked>> | 82% | 54,085 psi | 87% | 2349 fps | 100% |
| Norma 202 | <<locked>> | 82% | 54,694 psi | 88% | 2346 fps | 100% |
| Norma 203B | <<locked>> | 84% | 53,026 psi | 85% | 2388 fps | 100% |
| Norma 204 | <<locked>> | 94% | 54,810 psi | 88% | 2461 fps | 98.6% |
| Norma MRPᴾ | <<locked>> | 100% | 52,547 psi | 84% | 2530 fps | 99.5% |
| Norma URP | <<locked>> | 94% | 54,998 psi | 88% | 2461 fps | 100% |
| Ramshot Big Game | <<locked>> | 84% | 53,461 psi | 86% | 2411 fps | 100% |
| Ramshot Grandᴾ | <<locked>> | 100% | 48,602 psi | 78% | 2444 fps | 96.9% |
| Ramshot Hunter | <<locked>> | 94% | 53,563 psi | 86% | 2464 fps | 99.9% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 43,178 psi | 69% | 2339 fps | 97.3% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,927 psi | 59% | 1486 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 86% | 54,592 psi | 88% | 2402 fps | 99.8% |
| ReloadSwiss RS 52 | <<locked>> | 82% | 54,607 psi | 88% | 2457 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 88% | 54,085 psi | 87% | 2487 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 94% | 55,898 psi | 90% | 2497 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 94% | 54,534 psi | 87% | 2523 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 39,726 psi | 64% | 2356 fps | 97.3% |
| Rottweil R 902 | <<locked>> | 84% | 54,665 psi | 88% | 2349 fps | 100% |
| Rottweil R 903 | <<locked>> | 88% | 54,244 psi | 87% | 2392 fps | 100% |
| Rottweil R 904 | <<locked>> | 98% | 55,376 psi | 89% | 2438 fps | 97.9% |
| Rottweil R 905ᴾ | <<locked>> | 100% | 55,463 psi | 89% | 2490 fps | 99% |
| Rottweil R 907 | <<locked>> | 90% | 53,606 psi | 86% | 2385 fps | 99.2% |
| Shooters World Long Rifle | <<locked>> | 92% | 55,317 psi | 89% | 2408 fps | 100% |
| Shooters World Match Rifle | <<locked>> | 82% | 55,564 psi | 89% | 2375 fps | 100% |
| Shooters World Precision | <<locked>> | 86% | 55,941 psi | 90% | 2382 fps | 100% |
| Shooters World SW4350 | <<locked>> | 92% | 52,968 psi | 85% | 2398 fps | 99.5% |
| SNPE Vectan SP 11 | <<locked>> | 88% | 55,796 psi | 89% | 2448 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 82% | 56,260 psi | 90% | 2408 fps | 100% |
| SNPE Vectan SP 9 | <<locked>> | 82% | 53,635 psi | 86% | 2379 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 82% | 55,071 psi | 88% | 2287 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 88% | 55,593 psi | 89% | 2290 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 92% | 54,955 psi | 88% | 2365 fps | 99.6% |
| SNPE Vectan Tubal 8000ᴾ | <<locked>> | 100% | 54,969 psi | 88% | 2487 fps | 98.9% |
| Somchem S335 | <<locked>> | 82% | 54,650 psi | 88% | 2287 fps | 100% |
| Somchem S341 | <<locked>> | 82% | 55,970 psi | 90% | 2395 fps | 100% |
| Somchem S355 | <<locked>> | 88% | 54,201 psi | 87% | 2388 fps | 100% |
| Somchem S361 | <<locked>> | 96% | 53,505 psi | 86% | 2392 fps | 96.7% |
| Somchem S365 | <<locked>> | 96% | 53,911 psi | 86% | 2464 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 55,999 psi | 90% | 2467 fps | 99.4% |
| Vihtavuori N133 | <<locked>> | 82% | 55,535 psi | 89% | 2270 fps | 100% |
| Vihtavuori N135 | <<locked>> | 84% | 55,013 psi | 88% | 2313 fps | 100% |
| Vihtavuori N140 | <<locked>> | 84% | 55,129 psi | 88% | 2326 fps | 100% |
| Vihtavuori N150 | <<locked>> | 90% | 55,463 psi | 89% | 2365 fps | 100% |
| Vihtavuori N160 | <<locked>> | 92% | 53,664 psi | 86% | 2411 fps | 100% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 48,428 psi | 78% | 2356 fps | 98.2% |
| Vihtavuori N540 | <<locked>> | 84% | 53,374 psi | 86% | 2329 fps | 100% |
| Vihtavuori N550 | <<locked>> | 94% | 56,086 psi | 90% | 2461 fps | 100% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 52,605 psi | 84% | 2467 fps | 100% |
| Vihtavuori N560ᴾ | <<locked>> | 100% | 53,113 psi | 85% | 2523 fps | 97.2% |
| Winchester 6.5 StaBALL | <<locked>> | 92% | 53,011 psi | 85% | 2385 fps | 100% |
| Winchester 760 | <<locked>> | 92% | 55,071 psi | 88% | 2477 fps | 99.7% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 42,221 psi | 68% | 2454 fps | 100% |
| Winchester StaBALL Match | <<locked>> | 82% | 53,635 psi | 86% | 2385 fps | 100% |
| Winchester Supreme 780ᴾ | <<locked>> | 100% | 52,489 psi | 84% | 2418 fps | 98.3% |
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 2495 | <<locked>> | 80% | 49,197 psi | 79% | 2247 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 47,152 psi | 76% | 2257 fps | 98.1% |
| Accurate 3100 | <<locked>> | 86% | 31,314 psi | 50% | 2067 fps | 95.7% |
| Accurate 4064 | <<locked>> | 80% | 46,586 psi | 75% | 2257 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 34,983 psi | 56% | 2149 fps | 98.6% |
| Accurate MAGPRO | <<locked>> | 98% | 48,167 psi | 77% | 2454 fps | 95.4% |
| ADI AR 2206H | <<locked>> | 80% | 51,793 psi | 83% | 2356 fps | 100% |
| ADI AR 2208 | <<locked>> | 80% | 44,237 psi | 71% | 2238 fps | 99.9% |
| ADI AR 2209 | <<locked>> | 88% | 38,986 psi | 63% | 2228 fps | 95.2% |
| ADI AR 2213 | <<locked>> | 96% | 44,962 psi | 72% | 2359 fps | 95.4% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 48,037 psi | 77% | 2415 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 44,512 psi | 71% | 2257 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 47,369 psi | 76% | 2313 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 34,490 psi | 55% | 2159 fps | 98.7% |
| Alliant Reloder-17 | <<locked>> | 80% | 38,827 psi | 62% | 2264 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 88% | 38,566 psi | 62% | 2224 fps | 95.2% |
| Alliant Reloder-22 | <<locked>> | 92% | 38,421 psi | 62% | 2264 fps | 95.4% |
| Alliant Reloder-23 | <<locked>> | 80% | 25,280 psi | 41% | 1962 fps | 96.7% |
| Alliant Reloder-25 | <<locked>> | 90% | 30,197 psi | 48% | 2100 fps | 95.5% |
| Alliant Reloder-26 | <<locked>> | 82% | 28,384 psi | 46% | 2096 fps | 95.7% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 51,372 psi | 82% | 2372 fps | 100% |
| Bofors RP15 | <<locked>> | 94% | 37,913 psi | 61% | 2254 fps | 95% |
| Bofors RP3 | <<locked>> | 80% | 44,483 psi | 71% | 2267 fps | 100% |
| Bofors RP5 | <<locked>> | 92% | 38,421 psi | 62% | 2264 fps | 95.4% |
| Bofors RP7 | <<locked>> | 80% | 39,407 psi | 63% | 2159 fps | 96.6% |
| Hodgdon H380 | <<locked>> | 80% | 44,976 psi | 72% | 2277 fps | 99.7% |
| Hodgdon H414 | 55.2 gr | 80% | 36,956 psi | 59% | 2188 fps | 96.6% |
| Hodgdon H4350 | <<locked>> | 80% | 40,089 psi | 64% | 2205 fps | 96.1% |
| Hodgdon H4831 | <<locked>> | 96% | 48,066 psi | 77% | 2365 fps | 95.6% |
| Hodgdon H4831 SC | <<locked>> | 96% | 47,108 psi | 76% | 2349 fps | 95.4% |
| Hodgdon H4895 | <<locked>> | 80% | 52,388 psi | 84% | 2362 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 32,082 psi | 51% | 2070 fps | 99.1% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 48,820 psi | 78% | 2352 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 98% | 37,782 psi | 61% | 2310 fps | 95.3% |
| Hodgdon Superformance | <<locked>> | 80% | 35,940 psi | 58% | 2198 fps | 95.7% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,064 psi | 43% | 1293 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 50,256 psi | 81% | 2323 fps | 100% |
| IMR 3031 | <<locked>> | 80% | 52,953 psi | 85% | 2339 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 46,514 psi | 75% | 2264 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 80% | 48,733 psi | 78% | 2290 fps | 98.9% |
| IMR 4350 | <<locked>> | 80% | 35,157 psi | 56% | 2100 fps | 95.3% |
| IMR 4451 Enduron | <<locked>> | 80% | 40,901 psi | 66% | 2188 fps | 97.4% |
| IMR 4831 | <<locked>> | 80% | 33,866 psi | 54% | 2113 fps | 98.3% |
| IMR 4895 | <<locked>> | 80% | 48,588 psi | 78% | 2336 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 94% | 47,094 psi | 76% | 2316 fps | 95.6% |
| IMR 7828 SSC | <<locked>> | 98% | 45,556 psi | 73% | 2382 fps | 95.7% |
| Lovex D073.6 | <<locked>> | 80% | 52,011 psi | 83% | 2333 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 51,169 psi | 82% | 2293 fps | 100% |
| Lovex S062 | <<locked>> | 80% | 46,659 psi | 75% | 2260 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 38,493 psi | 62% | 2149 fps | 98.2% |
| Lovex S070 | <<locked>> | 80% | 36,724 psi | 59% | 2133 fps | 96.7% |
| Lovex S071 | <<locked>> | 90% | 30,400 psi | 49% | 2047 fps | 95.4% |
| Norma 201 | <<locked>> | 80% | 50,894 psi | 82% | 2310 fps | 100% |
| Norma 202 | <<locked>> | 80% | 51,474 psi | 83% | 2306 fps | 100% |
| Norma 203B | <<locked>> | 80% | 46,746 psi | 75% | 2300 fps | 100% |
| Norma 204 | <<locked>> | 84% | 39,378 psi | 63% | 2221 fps | 95.3% |
| Norma MRP | <<locked>> | 88% | 35,186 psi | 56% | 2228 fps | 95.8% |
| Norma URP | <<locked>> | 80% | 35,128 psi | 56% | 2149 fps | 98.5% |
| Ramshot Big Game | <<locked>> | 80% | 46,731 psi | 75% | 2323 fps | 100% |
| Ramshot Grand | <<locked>> | 96% | 42,525 psi | 68% | 2339 fps | 95.1% |
| Ramshot Hunter | <<locked>> | 80% | 33,939 psi | 54% | 2136 fps | 96.5% |
| Ramshot Magnum | <<locked>> | 96% | 37,608 psi | 60% | 2238 fps | 95.6% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,630 psi | 44% | 1325 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 45,063 psi | 72% | 2264 fps | 98.8% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 51,039 psi | 82% | 2411 fps | 100% |
| ReloadSwiss RS 60 | 56.5 gr | 80% | 41,278 psi | 66% | 2306 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 34,621 psi | 56% | 2165 fps | 98.2% |
| ReloadSwiss RS 70 | 57.3 gr | 80% | 33,866 psi | 54% | 2169 fps | 97.6% |
| ReloadSwiss RS 76 | <<locked>> | 96% | 34,693 psi | 56% | 2241 fps | 95.1% |
| Rottweil R 902 | <<locked>> | 80% | 48,414 psi | 78% | 2267 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 42,047 psi | 67% | 2224 fps | 100% |
| Rottweil R 904 | <<locked>> | 90% | 43,105 psi | 69% | 2257 fps | 95.2% |
| Rottweil R 905 | <<locked>> | 88% | 37,536 psi | 60% | 2208 fps | 95.2% |
| Rottweil R 907 | <<locked>> | 80% | 39,407 psi | 63% | 2159 fps | 96.6% |
| Shooters World Long Rifle | <<locked>> | 80% | 38,493 psi | 62% | 2149 fps | 98.2% |
| Shooters World Match Rifle | <<locked>> | 80% | 52,011 psi | 83% | 2333 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 46,659 psi | 75% | 2260 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 36,724 psi | 59% | 2133 fps | 96.7% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 42,946 psi | 69% | 2270 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 52,765 psi | 85% | 2362 fps | 100% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 50,299 psi | 81% | 2333 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 51,721 psi | 83% | 2247 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 43,613 psi | 70% | 2142 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 37,637 psi | 60% | 2100 fps | 96.7% |
| SNPE Vectan Tubal 8000 | <<locked>> | 88% | 37,188 psi | 60% | 2205 fps | 95% |
| Somchem S335 | <<locked>> | 80% | 51,517 psi | 83% | 2251 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 52,243 psi | 84% | 2349 fps | 100% |
| Somchem S355 | <<locked>> | 80% | 42,496 psi | 68% | 2224 fps | 100% |
| Somchem S361 | <<locked>> | 92% | 47,050 psi | 75% | 2300 fps | 95.3% |
| Somchem S365 | <<locked>> | 80% | 31,488 psi | 50% | 2110 fps | 99.8% |
| Somchem S385 | <<locked>> | 86% | 35,708 psi | 57% | 2149 fps | 95.5% |
| Vihtavuori N133 | <<locked>> | 80% | 52,228 psi | 84% | 2231 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 48,530 psi | 78% | 2234 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 48,849 psi | 78% | 2251 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 40,538 psi | 65% | 2165 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 36,361 psi | 58% | 2142 fps | 98.7% |
| Vihtavuori N165 | <<locked>> | 92% | 37,405 psi | 60% | 2175 fps | 95.5% |
| Vihtavuori N540 | <<locked>> | 80% | 46,949 psi | 75% | 2247 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 35,839 psi | 57% | 2149 fps | 98.4% |
| Vihtavuori N555 | <<locked>> | 80% | 27,456 psi | 44% | 2021 fps | 96.7% |
| Vihtavuori N560 | <<locked>> | 96% | 46,514 psi | 75% | 2418 fps | 95.7% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 35,534 psi | 57% | 2119 fps | 99.8% |
| Winchester 760 | <<locked>> | 80% | 37,130 psi | 60% | 2192 fps | 96.7% |
| Winchester StaBALL HD | <<locked>> | 82% | 23,685 psi | 38% | 1985 fps | 96.3% |
| Winchester StaBALL Match | <<locked>> | 80% | 50,256 psi | 81% | 2343 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 92% | 40,001 psi | 64% | 2224 fps | 95.6% |
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 112 powders for .338 Win Mag. loaded with the .338 | 275gr | Speer SSP. Alliant Reloder-26 delivers the highest muzzle velocity at 2,569 fps; across all powders the maximum-charge window runs from 1,450 fps to 2,569 fps. Accurate 3100 gives the best case fill at 100 %, and 112 of the 112 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (430 MPa), the top charges use 53–90 %, leaving at least 10 % headroom. The 275.0 gr projectile in 0.338" calls for a 1:16.0 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, ReloadSwiss RS 60, Hodgdon H414 rank at the top here: for .338 Win Mag. with the .338 | 275gr | Speer SSP they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, ADI AR 2217, ADI AR 2225, Baschieri & Pellagri 109 burn incompletely and react more sensitively to barrel length and temperature. Always begin at the start load and work up in small increments while checking case and primer for pressure signs.