Load Specifications
Bullet Manufacturer:Discreet Ballistics
Bullet Weight:280 gr
Bullet Diameter:0.338"
Bullet Length:<<locked>>
Caliber:.338 Weatherby RPM load data
Case Length (l3):2.55"
Cartridge Length (C.O.L.):<<locked>>
Case Capacity:81.6 Grains of Water
Primer Size:Large Rifle Magnum (LRM)
Barrel Length:24"
Max. allowed Pressure:65,000 psi
Recommended Twist Rate:1:14.0
Load data in caliber .338 Weatherby RPM with .338 | 280gr | Discreet Ballistics Selous Machined Expander bullet and 111 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Hodgdon Superformance, 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>> | 84% | 58,363 psi | 90% | 2257 fps | 100% |
| Accurate 2495 | <<locked>> | 88% | 57,203 psi | 88% | 2283 fps | 100% |
| Accurate 2520 | <<locked>> | 82% | 55,013 psi | 85% | 2300 fps | 100% |
| Accurate 2700 | <<locked>> | 88% | 55,883 psi | 86% | 2306 fps | 98.8% |
| Accurate 3100ᴾ | <<locked>> | 100% | 43,874 psi | 67% | 2241 fps | 98.5% |
| Accurate 4064 | <<locked>> | 90% | 57,246 psi | 88% | 2329 fps | 100% |
| Accurate 4350 | <<locked>> | 98% | 57,130 psi | 88% | 2421 fps | 100% |
| ADI AR 2206H | <<locked>> | 86% | 57,348 psi | 88% | 2359 fps | 100% |
| ADI AR 2208 | <<locked>> | 92% | 58,305 psi | 90% | 2362 fps | 100% |
| ADI AR 2209ᴾ | <<locked>> | 100% | 51,590 psi | 79% | 2365 fps | 97.5% |
| ADI Benchmark 8208 | <<locked>> | 84% | 56,275 psi | 87% | 2313 fps | 100% |
| Alliant AR-Comp | <<locked>> | 84% | 57,537 psi | 89% | 2280 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 88% | 56,985 psi | 88% | 2470 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 92% | 58,508 psi | 90% | 2379 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 88% | 55,579 psi | 86% | 2359 fps | 100% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 57,870 psi | 89% | 2464 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 94% | 55,796 psi | 86% | 2451 fps | 100% |
| Alliant Reloder-19ᴾ | <<locked>> | 100% | 50,444 psi | 78% | 2356 fps | 97.5% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 44,280 psi | 68% | 2306 fps | 96.3% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 41,698 psi | 64% | 2264 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 36,767 psi | 57% | 2192 fps | 97.4% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 46,528 psi | 72% | 2408 fps | 99.8% |
| Baschieri & Pellagri 107 | <<locked>> | 86% | 57,029 psi | 88% | 2379 fps | 100% |
| Bofors RP3 | <<locked>> | 90% | 55,724 psi | 86% | 2352 fps | 100% |
| Bofors RP5ᴾ | <<locked>> | 100% | 44,280 psi | 68% | 2306 fps | 96.3% |
| Bofors RP7 | <<locked>> | 94% | 55,332 psi | 85% | 2336 fps | 98.9% |
| Hodgdon Benchmark | <<locked>> | 84% | 57,769 psi | 89% | 2293 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 84% | 55,724 psi | 86% | 2343 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 82% | 57,812 psi | 89% | 2431 fps | 100% |
| Hodgdon H380 | <<locked>> | 90% | 56,550 psi | 87% | 2369 fps | 100% |
| Hodgdon H414 | <<locked>> | 96% | 56,072 psi | 86% | 2421 fps | 99.4% |
| Hodgdon H4350 | <<locked>> | 94% | 56,637 psi | 87% | 2388 fps | 98.7% |
| Hodgdon H4895 | <<locked>> | 86% | 57,928 psi | 89% | 2365 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 54,244 psi | 83% | 2356 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 88% | 57,377 psi | 88% | 2395 fps | 100% |
| Hodgdon Superformance | <<locked>> | 96% | 56,463 psi | 87% | 2461 fps | 99.3% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,853 psi | 55% | 1388 fps | 100% |
| Hodgdon VARGET | <<locked>> | 86% | 55,477 psi | 85% | 2326 fps | 100% |
| IMR 3031 | <<locked>> | 86% | 58,218 psi | 90% | 2339 fps | 100% |
| IMR 4064 | <<locked>> | 90% | 57,798 psi | 89% | 2346 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 88% | 57,479 psi | 88% | 2336 fps | 99.4% |
| IMR 4350 | <<locked>> | 98% | 55,738 psi | 86% | 2362 fps | 99% |
| IMR 4451 Enduron | <<locked>> | 94% | 57,232 psi | 88% | 2362 fps | 99.4% |
| IMR 4831ᴾ | <<locked>> | 100% | 57,392 psi | 88% | 2411 fps | 100% |
| IMR 4895 | <<locked>> | 88% | 57,000 psi | 88% | 2382 fps | 100% |
| IMR 4955 Enduronᴾ | <<locked>> | 100% | 51,430 psi | 79% | 2306 fps | 95.7% |
| IMR 8208 XBR | <<locked>> | 84% | 56,275 psi | 87% | 2313 fps | 100% |
| Lovex D073.6 | <<locked>> | 86% | 57,464 psi | 88% | 2336 fps | 100% |
| Lovex S060 | <<locked>> | 86% | 56,652 psi | 87% | 2293 fps | 100% |
| Lovex S062 | <<locked>> | 90% | 57,653 psi | 89% | 2339 fps | 100% |
| Lovex S065 | <<locked>> | 96% | 56,652 psi | 87% | 2356 fps | 99.9% |
| Lovex S070 | <<locked>> | 98% | 57,827 psi | 89% | 2392 fps | 99.6% |
| Lovex S071ᴾ | <<locked>> | 100% | 36,492 psi | 56% | 2119 fps | 96.8% |
| Norma 201 | <<locked>> | 86% | 55,883 psi | 86% | 2306 fps | 100% |
| Norma 202 | <<locked>> | 86% | 56,521 psi | 87% | 2303 fps | 100% |
| Norma 203B | <<locked>> | 90% | 58,276 psi | 90% | 2388 fps | 100% |
| Norma 204 | <<locked>> | 98% | 56,231 psi | 87% | 2408 fps | 98.2% |
| Norma MRPᴾ | <<locked>> | 100% | 46,398 psi | 71% | 2372 fps | 98.2% |
| Norma URP | <<locked>> | 98% | 56,014 psi | 86% | 2411 fps | 100% |
| Ramshot Big Game | <<locked>> | 88% | 55,071 psi | 85% | 2369 fps | 100% |
| Ramshot Hunterᴾ | <<locked>> | 100% | 58,262 psi | 90% | 2457 fps | 99.9% |
| Ramshot TAC | <<locked>> | 84% | 56,188 psi | 86% | 2339 fps | 99.9% |
| Ramshot Wild Boar | <<locked>> | 84% | 55,956 psi | 86% | 2352 fps | 100% |
| Ramshot X-Terminator | <<locked>> | 82% | 56,884 psi | 88% | 2320 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,434 psi | 56% | 1421 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 90% | 56,666 psi | 87% | 2356 fps | 99.7% |
| ReloadSwiss RS 52 | <<locked>> | 86% | 56,318 psi | 87% | 2418 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 92% | 55,419 psi | 85% | 2444 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 98% | 56,579 psi | 87% | 2441 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 98% | 55,956 psi | 86% | 2470 fps | 100% |
| Rottweil R 901 | <<locked>> | 84% | 56,942 psi | 88% | 2283 fps | 100% |
| Rottweil R 902 | <<locked>> | 88% | 56,608 psi | 87% | 2310 fps | 100% |
| Rottweil R 903 | <<locked>> | 92% | 55,564 psi | 85% | 2346 fps | 100% |
| Rottweil R 904ᴾ | <<locked>> | 100% | 53,447 psi | 82% | 2343 fps | 96.8% |
| Rottweil R 905ᴾ | <<locked>> | 100% | 49,414 psi | 76% | 2343 fps | 97.5% |
| Rottweil R 907 | <<locked>> | 94% | 55,332 psi | 85% | 2336 fps | 98.9% |
| Shooters World Long Rifle | <<locked>> | 96% | 56,652 psi | 87% | 2356 fps | 99.9% |
| Shooters World Match Rifle | <<locked>> | 86% | 57,464 psi | 88% | 2336 fps | 100% |
| Shooters World Precision | <<locked>> | 90% | 57,653 psi | 89% | 2339 fps | 100% |
| Shooters World SW4350 | <<locked>> | 98% | 57,827 psi | 89% | 2392 fps | 99.6% |
| SNPE Vectan SP 11 | <<locked>> | 92% | 57,145 psi | 88% | 2402 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 86% | 58,508 psi | 90% | 2365 fps | 100% |
| SNPE Vectan SP 9 | <<locked>> | 86% | 55,724 psi | 86% | 2339 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 86% | 57,566 psi | 89% | 2251 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 92% | 57,725 psi | 89% | 2251 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 96% | 56,884 psi | 88% | 2320 fps | 99.3% |
| SNPE Vectan Tubal 8000ᴾ | <<locked>> | 100% | 48,979 psi | 75% | 2339 fps | 97.4% |
| Somchem S321 | <<locked>> | 82% | 57,334 psi | 88% | 2339 fps | 100% |
| Somchem S335 | <<locked>> | 86% | 56,623 psi | 87% | 2247 fps | 100% |
| Somchem S341 | <<locked>> | 86% | 58,146 psi | 89% | 2356 fps | 100% |
| Somchem S355 | <<locked>> | 92% | 55,796 psi | 86% | 2343 fps | 100% |
| Somchem S361ᴾ | <<locked>> | 100% | 54,926 psi | 85% | 2336 fps | 96.1% |
| Somchem S365ᴾ | <<locked>> | 100% | 54,085 psi | 83% | 2408 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 50,096 psi | 77% | 2326 fps | 98.3% |
| Vihtavuori N130 | <<locked>> | 82% | 57,203 psi | 88% | 2211 fps | 100% |
| Vihtavuori N133 | <<locked>> | 86% | 57,856 psi | 89% | 2231 fps | 100% |
| Vihtavuori N135 | <<locked>> | 88% | 56,579 psi | 87% | 2270 fps | 100% |
| Vihtavuori N140 | <<locked>> | 88% | 57,087 psi | 88% | 2287 fps | 100% |
| Vihtavuori N150 | <<locked>> | 94% | 57,203 psi | 88% | 2323 fps | 100% |
| Vihtavuori N160 | <<locked>> | 98% | 58,494 psi | 90% | 2402 fps | 100% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 43,105 psi | 66% | 2211 fps | 96.4% |
| Vihtavuori N530 | <<locked>> | 84% | 56,637 psi | 87% | 2310 fps | 100% |
| Vihtavuori N540 | <<locked>> | 90% | 58,769 psi | 90% | 2329 fps | 100% |
| Vihtavuori N550 | <<locked>> | 98% | 57,334 psi | 88% | 2411 fps | 100% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 46,079 psi | 71% | 2323 fps | 99.9% |
| Winchester 6.5 StaBALL | <<locked>> | 98% | 58,421 psi | 90% | 2382 fps | 100% |
| Winchester 748 | <<locked>> | 84% | 56,753 psi | 87% | 2352 fps | 100% |
| Winchester 760 | <<locked>> | 96% | 56,318 psi | 87% | 2425 fps | 99.5% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 37,347 psi | 57% | 2293 fps | 100% |
| Winchester StaBALL Match | <<locked>> | 86% | 55,535 psi | 85% | 2346 fps | 100% |
| Winchester Supreme 780ᴾ | <<locked>> | 100% | 46,905 psi | 72% | 2270 fps | 96.5% |
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% | 51,735 psi | 80% | 2185 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 44,382 psi | 68% | 2133 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 51,648 psi | 79% | 2260 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 43,294 psi | 67% | 2129 fps | 96.6% |
| Accurate 3100 | <<locked>> | 90% | 31,415 psi | 48% | 2021 fps | 95.1% |
| Accurate 4064 | <<locked>> | 80% | 42,032 psi | 65% | 2139 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 31,140 psi | 48% | 2018 fps | 96.9% |
| ADI AR 2206H | <<locked>> | 80% | 47,688 psi | 73% | 2234 fps | 100% |
| ADI AR 2208 | <<locked>> | 80% | 40,422 psi | 62% | 2116 fps | 99.4% |
| ADI AR 2209 | <<locked>> | 94% | 42,699 psi | 66% | 2228 fps | 95.4% |
| ADI Benchmark 8208 | <<locked>> | 80% | 49,777 psi | 77% | 2234 fps | 100% |
| Alliant AR-Comp | <<locked>> | 80% | 50,705 psi | 78% | 2208 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 43,482 psi | 67% | 2280 fps | 99.8% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 40,451 psi | 62% | 2139 fps | 99.9% |
| Alliant Reloder-15 | <<locked>> | 80% | 43,366 psi | 67% | 2192 fps | 99.8% |
| Alliant Reloder-16 | <<locked>> | 80% | 31,386 psi | 48% | 2028 fps | 97.1% |
| Alliant Reloder-17 | 50.6 gr | 80% | 34,838 psi | 54% | 2129 fps | 99.4% |
| Alliant Reloder-19 | <<locked>> | 94% | 41,974 psi | 65% | 2221 fps | 95.5% |
| Alliant Reloder-22 | <<locked>> | 98% | 41,582 psi | 64% | 2260 fps | 95.5% |
| Alliant Reloder-23 | <<locked>> | 82% | 24,207 psi | 37% | 1877 fps | 95.1% |
| Alliant Reloder-25 | <<locked>> | 96% | 32,605 psi | 50% | 2096 fps | 95.7% |
| Alliant Reloder-26 | <<locked>> | 86% | 28,950 psi | 45% | 2054 fps | 95% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 46,775 psi | 72% | 2247 fps | 99.8% |
| Bofors RP3 | <<locked>> | 80% | 40,205 psi | 62% | 2142 fps | 100% |
| Bofors RP5 | <<locked>> | 98% | 41,582 psi | 64% | 2260 fps | 95.5% |
| Bofors RP7 | <<locked>> | 82% | 38,319 psi | 59% | 2077 fps | 95.5% |
| Hodgdon Benchmark | <<locked>> | 80% | 51,184 psi | 79% | 2215 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 48,733 psi | 75% | 2257 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 80% | 53,983 psi | 83% | 2385 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 40,857 psi | 63% | 2149 fps | 98.8% |
| Hodgdon H414 | <<locked>> | 82% | 35,433 psi | 55% | 2100 fps | 95.4% |
| Hodgdon H4350 | <<locked>> | 84% | 41,365 psi | 64% | 2165 fps | 95.7% |
| Hodgdon H4895 | <<locked>> | 80% | 48,211 psi | 74% | 2244 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 28,892 psi | 44% | 1949 fps | 97.8% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 44,150 psi | 68% | 2228 fps | 100% |
| Hodgdon Superformance | 56.2 gr | 84% | 37,173 psi | 57% | 2159 fps | 95.3% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,890 psi | 41% | 1240 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 46,035 psi | 71% | 2201 fps | 100% |
| IMR 3031 | <<locked>> | 80% | 48,066 psi | 74% | 2224 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 42,482 psi | 65% | 2139 fps | 99.7% |
| IMR 4166 Enduron | <<locked>> | 80% | 44,846 psi | 69% | 2162 fps | 97.7% |
| IMR 4350 | <<locked>> | 86% | 38,566 psi | 59% | 2106 fps | 95.6% |
| IMR 4451 Enduron | <<locked>> | 80% | 37,536 psi | 58% | 2064 fps | 95.8% |
| IMR 4831 | <<locked>> | 80% | 30,168 psi | 46% | 1985 fps | 96.6% |
| IMR 4895 | <<locked>> | 80% | 44,454 psi | 68% | 2215 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 98% | 48,370 psi | 74% | 2264 fps | 95% |
| IMR 8208 XBR | <<locked>> | 80% | 49,777 psi | 77% | 2234 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 47,021 psi | 72% | 2211 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 47,224 psi | 73% | 2172 fps | 100% |
| Lovex S062 | <<locked>> | 80% | 42,482 psi | 65% | 2139 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 35,041 psi | 54% | 2024 fps | 96.6% |
| Lovex S070 | <<locked>> | 82% | 35,317 psi | 54% | 2047 fps | 95.5% |
| Lovex S071 | <<locked>> | 96% | 32,285 psi | 50% | 2041 fps | 95.4% |
| Norma 201 | <<locked>> | 80% | 46,615 psi | 72% | 2188 fps | 100% |
| Norma 202 | <<locked>> | 80% | 47,123 psi | 72% | 2192 fps | 100% |
| Norma 203B | <<locked>> | 80% | 42,743 psi | 66% | 2182 fps | 99.9% |
| Norma 204 | <<locked>> | 90% | 43,337 psi | 67% | 2224 fps | 95.6% |
| Norma MRP | <<locked>> | 92% | 35,752 psi | 55% | 2178 fps | 95.1% |
| Norma URP | <<locked>> | 80% | 31,357 psi | 48% | 2018 fps | 96.8% |
| Ramshot Big Game | <<locked>> | 80% | 42,221 psi | 65% | 2195 fps | 99.8% |
| Ramshot Hunter | <<locked>> | 82% | 32,648 psi | 50% | 2051 fps | 95.2% |
| Ramshot TAC | <<locked>> | 80% | 49,385 psi | 76% | 2251 fps | 99.5% |
| Ramshot Wild Boar | <<locked>> | 80% | 49,298 psi | 76% | 2267 fps | 100% |
| Ramshot X-Terminator | <<locked>> | 80% | 53,316 psi | 82% | 2274 fps | 100% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,267 psi | 42% | 1270 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 41,133 psi | 63% | 2136 fps | 97.5% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 45,832 psi | 71% | 2277 fps | 99.9% |
| ReloadSwiss RS 60 | 50.6 gr | 80% | 37,043 psi | 57% | 2175 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 30,792 psi | 47% | 2034 fps | 96.4% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 30,705 psi | 47% | 2034 fps | 95.3% |
| Rottweil R 901 | <<locked>> | 80% | 50,676 psi | 78% | 2208 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 44,382 psi | 68% | 2152 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 37,797 psi | 58% | 2100 fps | 99.7% |
| Rottweil R 904 | <<locked>> | 96% | 47,094 psi | 72% | 2251 fps | 95.4% |
| Rottweil R 905 | <<locked>> | 94% | 40,683 psi | 63% | 2205 fps | 95.4% |
| Rottweil R 907 | <<locked>> | 82% | 38,319 psi | 59% | 2077 fps | 95.5% |
| Shooters World Long Rifle | <<locked>> | 80% | 35,041 psi | 54% | 2024 fps | 96.6% |
| Shooters World Match Rifle | <<locked>> | 80% | 47,021 psi | 72% | 2211 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 42,482 psi | 65% | 2139 fps | 100% |
| Shooters World SW4350 | <<locked>> | 82% | 35,317 psi | 54% | 2047 fps | 95.5% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 38,682 psi | 60% | 2142 fps | 99.5% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 48,066 psi | 74% | 2234 fps | 99.6% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 45,934 psi | 71% | 2211 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 47,761 psi | 73% | 2136 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 39,972 psi | 61% | 2034 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 82% | 36,521 psi | 56% | 2021 fps | 95.7% |
| SNPE Vectan Tubal 8000 | <<locked>> | 94% | 40,321 psi | 62% | 2201 fps | 95.2% |
| Somchem S321 | <<locked>> | 80% | 53,693 psi | 83% | 2300 fps | 100% |
| Somchem S335 | <<locked>> | 80% | 47,471 psi | 73% | 2139 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 47,601 psi | 73% | 2224 fps | 100% |
| Somchem S355 | <<locked>> | 80% | 38,522 psi | 59% | 2100 fps | 99.7% |
| Somchem S361 | <<locked>> | 98% | 51,648 psi | 79% | 2293 fps | 95.4% |
| Somchem S365 | <<locked>> | 80% | 28,195 psi | 43% | 1985 fps | 98.8% |
| Somchem S385 | <<locked>> | 92% | 38,653 psi | 59% | 2146 fps | 95.7% |
| Vihtavuori N130 | <<locked>> | 80% | 53,751 psi | 83% | 2172 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 48,211 psi | 74% | 2126 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 44,164 psi | 68% | 2123 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 44,512 psi | 68% | 2136 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 36,608 psi | 56% | 2047 fps | 99.9% |
| Vihtavuori N160 | <<locked>> | 80% | 32,837 psi | 51% | 2021 fps | 97.2% |
| Vihtavuori N165 | <<locked>> | 98% | 40,480 psi | 62% | 2169 fps | 95.6% |
| Vihtavuori N530 | <<locked>> | 80% | 49,893 psi | 77% | 2231 fps | 100% |
| Vihtavuori N540 | <<locked>> | 80% | 42,888 psi | 66% | 2136 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 32,213 psi | 50% | 2021 fps | 96.8% |
| Vihtavuori N555 | <<locked>> | 82% | 25,860 psi | 40% | 1936 fps | 95.3% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 32,271 psi | 50% | 1998 fps | 98.9% |
| Winchester 748 | <<locked>> | 80% | 49,806 psi | 77% | 2270 fps | 100% |
| Winchester 760 | <<locked>> | 82% | 35,621 psi | 55% | 2106 fps | 95.5% |
| Winchester StaBALL HD | <<locked>> | 86% | 24,091 psi | 37% | 1936 fps | 95.4% |
| Winchester StaBALL Match | <<locked>> | 80% | 45,643 psi | 70% | 2218 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 98% | 43,903 psi | 68% | 2224 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 124 powders for .338 Weatherby RPM loaded with the .338 | 280gr | Discreet Ballistics Selous Machined Expander. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 2,470 fps; across all powders the maximum-charge window runs from 1,388 fps to 2,470 fps. Accurate 3100 gives the best case fill at 100 %, and 124 of the 124 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (448 MPa), the top charges use 54–90 %, leaving at least 10 % headroom. The 280.0 gr projectile in 0.338" calls for a 1:14.0 twist; slower twists will usually not stabilise this weight. Accurate 3100, Accurate MAGPRO, ADI AR 2209 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. Hodgdon Superformance, Alliant Reloder-17, ReloadSwiss RS 60 rank at the top here: for .338 Weatherby RPM with the .338 | 280gr | Discreet Ballistics Selous Machined Expander they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, Accurate MAGPRO, ADI AR 2213, Hodgdon H1000 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.