Load Specifications
Bullet:.338 | 250gr | Barnes TSX BT
Bullet Manufacturer:Barnes
Bullet Weight:250 gr
Bullet Diameter:0.338"
Bullet Length:<<locked>>
Caliber:.338 RCM load data
Case Length (l3):2"
Cartridge Length (C.O.L.):<<locked>>
Case Capacity:71 Grains of Water
Primer Size:Large Rifle (LR)
Barrel Length:24"
Max. allowed Pressure:62,366 psi
Recommended Twist Rate:1:12.5
Load data in caliber .338 RCM with .338 | 250gr | Barnes TSX BT bullet and 100 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, ReloadSwiss RS 52 and Hodgdon CFE223.
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>> | 90% | 54,853 psi | 88% | 2290 fps | 100% |
| Accurate 2200 | <<locked>> | 82% | 55,245 psi | 89% | 2375 fps | 99.5% |
| Accurate 2230 | <<locked>> | 82% | 56,260 psi | 90% | 2388 fps | 99.7% |
| Accurate 2460 | <<locked>> | 86% | 53,185 psi | 85% | 2316 fps | 100% |
| Accurate 2495 | <<locked>> | 96% | 55,347 psi | 89% | 2346 fps | 100% |
| Accurate 2520 | <<locked>> | 90% | 54,781 psi | 88% | 2369 fps | 100% |
| Accurate 4064 | <<locked>> | 98% | 54,592 psi | 88% | 2379 fps | 100% |
| Accurate 4350ᴾ | <<locked>> | 100% | 43,294 psi | 69% | 2300 fps | 97.7% |
| Accurate LT-30 | <<locked>> | 84% | 55,071 psi | 88% | 2244 fps | 100% |
| Accurate LT-32 | <<locked>> | 84% | 55,535 psi | 89% | 2267 fps | 100% |
| ADI AR 2206H | <<locked>> | 92% | 53,795 psi | 86% | 2375 fps | 99.8% |
| ADI AR 2208 | <<locked>> | 98% | 54,650 psi | 88% | 2369 fps | 99.5% |
| ADI AR 2219 | <<locked>> | 84% | 55,651 psi | 89% | 2352 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 90% | 53,272 psi | 85% | 2336 fps | 100% |
| Alliant AR-Comp | <<locked>> | 92% | 56,246 psi | 90% | 2352 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 86% | 54,795 psi | 88% | 2425 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 94% | 52,953 psi | 85% | 2467 fps | 99.4% |
| Alliant Reloder- TS 15.5 | <<locked>> | 98% | 53,534 psi | 86% | 2385 fps | 100% |
| Alliant Reloder-10x | <<locked>> | 86% | 54,897 psi | 88% | 2297 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 96% | 54,520 psi | 87% | 2405 fps | 99.6% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 44,019 psi | 71% | 2310 fps | 97.9% |
| Alliant Reloder-17ᴾ | <<locked>> | 100% | 50,546 psi | 81% | 2438 fps | 99.8% |
| Baschieri & Pellagri 106 | <<locked>> | 84% | 54,041 psi | 87% | 2247 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 92% | 53,171 psi | 85% | 2385 fps | 99.2% |
| Bofors RP3 | <<locked>> | 98% | 53,925 psi | 86% | 2402 fps | 100% |
| Bofors RP7ᴾ | <<locked>> | 100% | 51,692 psi | 83% | 2323 fps | 95.7% |
| Hodgdon Benchmark | <<locked>> | 90% | 55,550 psi | 89% | 2323 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 92% | 55,071 psi | 88% | 2405 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 88% | 53,403 psi | 86% | 2444 fps | 99.6% |
| Hodgdon H322 | <<locked>> | 86% | 53,867 psi | 86% | 2333 fps | 100% |
| Hodgdon H335 | <<locked>> | 86% | 54,810 psi | 88% | 2359 fps | 100% |
| Hodgdon H380 | <<locked>> | 98% | 55,593 psi | 89% | 2411 fps | 99% |
| Hodgdon H4895 | <<locked>> | 92% | 54,230 psi | 87% | 2382 fps | 99.9% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 40,234 psi | 65% | 2215 fps | 98.4% |
| Hodgdon LEVERevolution | <<locked>> | 96% | 56,188 psi | 90% | 2454 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 34,708 psi | 56% | 1381 fps | 100% |
| Hodgdon VARGET | <<locked>> | 94% | 55,869 psi | 90% | 2388 fps | 100% |
| IMR 3031 | <<locked>> | 92% | 53,127 psi | 85% | 2365 fps | 100% |
| IMR 4064 | <<locked>> | 96% | 54,157 psi | 87% | 2352 fps | 99.6% |
| IMR 4166 Enduron | <<locked>> | 94% | 55,259 psi | 89% | 2339 fps | 97% |
| IMR 4198 | <<locked>> | 86% | 55,463 psi | 89% | 2257 fps | 100% |
| IMR 4451 Enduronᴾ | <<locked>> | 100% | 53,751 psi | 86% | 2352 fps | 96.7% |
| IMR 4831ᴾ | <<locked>> | 100% | 41,727 psi | 67% | 2260 fps | 97.4% |
| IMR 4895 | <<locked>> | 96% | 55,869 psi | 90% | 2431 fps | 99.9% |
| IMR 8208 XBR | <<locked>> | 90% | 53,272 psi | 85% | 2336 fps | 100% |
| Lovex D073.5 | <<locked>> | 86% | 53,113 psi | 85% | 2326 fps | 100% |
| Lovex D073.6 | <<locked>> | 94% | 55,912 psi | 90% | 2392 fps | 100% |
| Lovex S060 | <<locked>> | 92% | 54,143 psi | 87% | 2313 fps | 99.7% |
| Lovex S062 | <<locked>> | 96% | 53,432 psi | 86% | 2352 fps | 100% |
| Lovex S065ᴾ | <<locked>> | 100% | 49,110 psi | 79% | 2300 fps | 97.3% |
| Norma 200 | <<locked>> | 82% | 55,013 psi | 88% | 2274 fps | 100% |
| Norma 201 | <<locked>> | 94% | 55,927 psi | 90% | 2369 fps | 100% |
| Norma 202 | <<locked>> | 94% | 56,072 psi | 90% | 2369 fps | 100% |
| Norma 203B | <<locked>> | 96% | 53,577 psi | 86% | 2395 fps | 99.8% |
| Norma URPᴾ | <<locked>> | 100% | 43,932 psi | 70% | 2303 fps | 97.7% |
| Ramshot Big Game | <<locked>> | 96% | 54,056 psi | 87% | 2418 fps | 99.7% |
| Ramshot TAC | <<locked>> | 90% | 53,563 psi | 86% | 2349 fps | 98.2% |
| Ramshot Wild Boar | <<locked>> | 92% | 56,304 psi | 90% | 2411 fps | 99.9% |
| Ramshot X-Terminator | <<locked>> | 88% | 54,650 psi | 88% | 2343 fps | 99.7% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 34,925 psi | 56% | 1414 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 86% | 52,953 psi | 85% | 2323 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 98% | 56,362 psi | 90% | 2392 fps | 97.8% |
| ReloadSwiss RS 52 | <<locked>> | 94% | 54,128 psi | 87% | 2457 fps | 99.6% |
| ReloadSwiss RS 60ᴾ | <<locked>> | 100% | 54,027 psi | 87% | 2490 fps | 100% |
| ReloadSwiss RS 62ᴾ | <<locked>> | 100% | 43,250 psi | 69% | 2320 fps | 97.3% |
| ReloadSwiss RS 70ᴾ | <<locked>> | 100% | 44,831 psi | 72% | 2336 fps | 96.7% |
| Rottweil R 901 | <<locked>> | 90% | 53,693 psi | 86% | 2313 fps | 100% |
| Rottweil R 902 | <<locked>> | 96% | 56,173 psi | 90% | 2365 fps | 100% |
| Rottweil R 903ᴾ | <<locked>> | 100% | 53,505 psi | 86% | 2388 fps | 99.9% |
| Rottweil R 907ᴾ | <<locked>> | 100% | 51,692 psi | 83% | 2323 fps | 95.7% |
| Shooters World Long Rifleᴾ | <<locked>> | 100% | 49,110 psi | 79% | 2300 fps | 97.3% |
| Shooters World Match Rifle | <<locked>> | 94% | 55,912 psi | 90% | 2392 fps | 100% |
| Shooters World Precision | <<locked>> | 96% | 53,432 psi | 86% | 2352 fps | 100% |
| Shooters World Tactical Rifle | <<locked>> | 84% | 52,866 psi | 85% | 2297 fps | 99.9% |
| SNPE Vectan BA6 1/2 | <<locked>> | 82% | 55,956 psi | 90% | 2031 fps | 100% |
| SNPE Vectan SP 10 | <<locked>> | 84% | 55,854 psi | 90% | 2362 fps | 100% |
| SNPE Vectan SP 11ᴾ | <<locked>> | 100% | 55,521 psi | 89% | 2444 fps | 99.8% |
| SNPE Vectan SP 3 | <<locked>> | 86% | 55,869 psi | 90% | 2310 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 92% | 55,187 psi | 88% | 2375 fps | 98.8% |
| SNPE Vectan SP 9 | <<locked>> | 94% | 55,317 psi | 89% | 2392 fps | 99.8% |
| SNPE Vectan Tubal 3000 | <<locked>> | 92% | 54,998 psi | 88% | 2280 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 98% | 54,041 psi | 87% | 2274 fps | 100% |
| SNPE Vectan Tubal 7000ᴾ | <<locked>> | 100% | 49,182 psi | 79% | 2260 fps | 95.9% |
| Somchem S321 | <<locked>> | 88% | 54,447 psi | 87% | 2372 fps | 100% |
| Somchem S335 | <<locked>> | 92% | 53,809 psi | 86% | 2280 fps | 100% |
| Somchem S341 | <<locked>> | 92% | 54,404 psi | 87% | 2365 fps | 99.7% |
| Somchem S355ᴾ | <<locked>> | 100% | 54,070 psi | 87% | 2385 fps | 99.9% |
| Somchem S365ᴾ | <<locked>> | 100% | 39,160 psi | 63% | 2260 fps | 99.4% |
| Vihtavuori N130 | <<locked>> | 88% | 54,940 psi | 88% | 2254 fps | 100% |
| Vihtavuori N133 | <<locked>> | 92% | 54,868 psi | 88% | 2267 fps | 100% |
| Vihtavuori N135 | <<locked>> | 96% | 55,129 psi | 88% | 2333 fps | 100% |
| Vihtavuori N140 | <<locked>> | 94% | 53,287 psi | 85% | 2316 fps | 100% |
| Vihtavuori N150ᴾ | <<locked>> | 100% | 52,417 psi | 84% | 2333 fps | 100% |
| Vihtavuori N160ᴾ | <<locked>> | 100% | 46,224 psi | 74% | 2300 fps | 97.9% |
| Vihtavuori N530 | <<locked>> | 90% | 53,751 psi | 86% | 2336 fps | 100% |
| Vihtavuori N540 | <<locked>> | 96% | 54,781 psi | 88% | 2356 fps | 100% |
| Vihtavuori N550ᴾ | <<locked>> | 100% | 45,092 psi | 72% | 2306 fps | 97.6% |
| Winchester 6.5 StaBALLᴾ | <<locked>> | 100% | 47,616 psi | 76% | 2293 fps | 99.5% |
| Winchester 748 | <<locked>> | 92% | 56,362 psi | 90% | 2418 fps | 100% |
| Winchester StaBALL Match | <<locked>> | 94% | 55,129 psi | 88% | 2402 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% | 40,451 psi | 65% | 2106 fps | 100% |
| Accurate 2200 | <<locked>> | 80% | 51,837 psi | 83% | 2329 fps | 99.2% |
| Accurate 2230 | <<locked>> | 80% | 52,417 psi | 84% | 2343 fps | 99.4% |
| Accurate 2460 | <<locked>> | 80% | 43,816 psi | 70% | 2195 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 32,938 psi | 53% | 2037 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 38,856 psi | 62% | 2152 fps | 99.7% |
| Accurate 4064 | <<locked>> | 80% | 31,154 psi | 50% | 2028 fps | 99.3% |
| Accurate 4350 | <<locked>> | 94% | 35,244 psi | 57% | 2165 fps | 95.6% |
| Accurate LT-30 | <<locked>> | 80% | 48,994 psi | 79% | 2172 fps | 100% |
| Accurate LT-32 | <<locked>> | 80% | 49,356 psi | 79% | 2192 fps | 100% |
| ADI AR 2206H | <<locked>> | 80% | 37,159 psi | 60% | 2119 fps | 97.4% |
| ADI AR 2208 | <<locked>> | 82% | 33,765 psi | 54% | 2037 fps | 95.5% |
| ADI AR 2219 | <<locked>> | 80% | 48,617 psi | 78% | 2267 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 80% | 39,146 psi | 63% | 2129 fps | 98.8% |
| Alliant AR-Comp | <<locked>> | 80% | 37,739 psi | 61% | 2126 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 80% | 45,194 psi | 72% | 2290 fps | 99.4% |
| Alliant Power Pro 2000-MR | 44 gr | 82% | 35,665 psi | 57% | 2172 fps | 95.6% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 30,487 psi | 49% | 2011 fps | 96.3% |
| Alliant Reloder-10x | <<locked>> | 80% | 45,963 psi | 74% | 2185 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 33,156 psi | 53% | 2060 fps | 95.5% |
| Alliant Reloder-16 | <<locked>> | 94% | 36,927 psi | 59% | 2178 fps | 95.8% |
| Alliant Reloder-17 | <<locked>> | 86% | 32,140 psi | 52% | 2106 fps | 95.9% |
| Baschieri & Pellagri 106 | <<locked>> | 80% | 47,529 psi | 76% | 2172 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 35,795 psi | 57% | 2113 fps | 95.7% |
| Bofors RP3 | <<locked>> | 80% | 29,733 psi | 48% | 2008 fps | 96.2% |
| Bofors RP7 | <<locked>> | 98% | 48,559 psi | 78% | 2277 fps | 95% |
| Hodgdon Benchmark | <<locked>> | 80% | 41,089 psi | 66% | 2123 fps | 99.4% |
| Hodgdon BL-C2 | <<locked>> | 80% | 36,970 psi | 59% | 2142 fps | 98.9% |
| Hodgdon CFE223 | 43.9 gr | 80% | 40,553 psi | 65% | 2247 fps | 97.7% |
| Hodgdon H322 | <<locked>> | 80% | 44,411 psi | 71% | 2211 fps | 100% |
| Hodgdon H335 | <<locked>> | 80% | 44,991 psi | 72% | 2231 fps | 100% |
| Hodgdon H380 | <<locked>> | 86% | 37,608 psi | 60% | 2142 fps | 95.5% |
| Hodgdon H4895 | <<locked>> | 80% | 37,434 psi | 60% | 2129 fps | 98% |
| Hodgdon Hybrid 100V | <<locked>> | 92% | 31,546 psi | 51% | 2047 fps | 95.8% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 33,402 psi | 54% | 2100 fps | 97.3% |
| Hodgdon TrailBoss | <<locked>> | 80% | 25,788 psi | 41% | 1234 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 35,911 psi | 58% | 2087 fps | 97.5% |
| IMR 3031 | <<locked>> | 80% | 36,143 psi | 58% | 2129 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 33,199 psi | 53% | 2021 fps | 95.6% |
| IMR 4166 Enduron | <<locked>> | 88% | 45,788 psi | 73% | 2208 fps | 95% |
| IMR 4198 | <<locked>> | 80% | 46,630 psi | 75% | 2156 fps | 100% |
| IMR 4451 Enduron | <<locked>> | 96% | 47,645 psi | 76% | 2267 fps | 95.4% |
| IMR 4831 | <<locked>> | 94% | 34,519 psi | 55% | 2129 fps | 95.3% |
| IMR 4895 | <<locked>> | 80% | 33,881 psi | 54% | 2087 fps | 96.5% |
| IMR 8208 XBR | <<locked>> | 80% | 39,146 psi | 63% | 2129 fps | 98.8% |
| Lovex D073.5 | <<locked>> | 80% | 43,468 psi | 70% | 2198 fps | 99.8% |
| Lovex D073.6 | <<locked>> | 80% | 35,259 psi | 57% | 2103 fps | 99.3% |
| Lovex S060 | <<locked>> | 80% | 38,043 psi | 61% | 2073 fps | 97.5% |
| Lovex S062 | <<locked>> | 80% | 32,866 psi | 53% | 2028 fps | 97.5% |
| Lovex S065 | <<locked>> | 94% | 41,162 psi | 66% | 2178 fps | 95.5% |
| Norma 200 | <<locked>> | 80% | 51,706 psi | 83% | 2234 fps | 100% |
| Norma 201 | <<locked>> | 80% | 36,448 psi | 58% | 2083 fps | 98.4% |
| Norma 202 | <<locked>> | 80% | 36,361 psi | 58% | 2093 fps | 99.7% |
| Norma 203B | <<locked>> | 80% | 32,561 psi | 52% | 2054 fps | 96% |
| Norma URP | <<locked>> | 94% | 36,419 psi | 58% | 2169 fps | 95.6% |
| Ramshot Big Game | <<locked>> | 80% | 31,937 psi | 51% | 2054 fps | 95.3% |
| Ramshot TAC | <<locked>> | 80% | 38,856 psi | 62% | 2126 fps | 95% |
| Ramshot Wild Boar | <<locked>> | 80% | 37,840 psi | 61% | 2142 fps | 97.5% |
| Ramshot X-Terminator | <<locked>> | 80% | 42,337 psi | 68% | 2169 fps | 98.3% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 25,846 psi | 41% | 1260 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 43,700 psi | 70% | 2198 fps | 99.9% |
| ReloadSwiss RS 50 | <<locked>> | 90% | 43,584 psi | 70% | 2218 fps | 95.3% |
| ReloadSwiss RS 52 | 41.6 gr | 80% | 33,968 psi | 54% | 2133 fps | 95.8% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 28,239 psi | 45% | 2018 fps | 96.8% |
| ReloadSwiss RS 62 | <<locked>> | 94% | 35,650 psi | 57% | 2182 fps | 95% |
| ReloadSwiss RS 70 | <<locked>> | 98% | 41,858 psi | 67% | 2287 fps | 95.8% |
| Rottweil R 901 | <<locked>> | 80% | 40,030 psi | 64% | 2119 fps | 99.9% |
| Rottweil R 902 | <<locked>> | 80% | 34,621 psi | 56% | 2041 fps | 97.9% |
| Rottweil R 903 | <<locked>> | 80% | 27,978 psi | 45% | 1962 fps | 95% |
| Rottweil R 907 | <<locked>> | 98% | 48,559 psi | 78% | 2277 fps | 95% |
| Shooters World Long Rifle | <<locked>> | 94% | 41,162 psi | 66% | 2178 fps | 95.5% |
| Shooters World Match Rifle | <<locked>> | 80% | 35,259 psi | 57% | 2103 fps | 99.3% |
| Shooters World Precision | <<locked>> | 80% | 32,866 psi | 53% | 2028 fps | 97.5% |
| Shooters World Tactical Rifle | <<locked>> | 80% | 46,354 psi | 74% | 2211 fps | 99.5% |
| SNPE Vectan BA6 1/2 | <<locked>> | 80% | 52,924 psi | 85% | 1998 fps | 100% |
| SNPE Vectan SP 10 | <<locked>> | 80% | 48,863 psi | 78% | 2277 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 82% | 31,241 psi | 50% | 2044 fps | 95.1% |
| SNPE Vectan SP 3 | <<locked>> | 80% | 46,644 psi | 75% | 2201 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 36,767 psi | 59% | 2100 fps | 95% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 35,665 psi | 57% | 2093 fps | 96.9% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 38,203 psi | 61% | 2054 fps | 99.8% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 31,285 psi | 50% | 1946 fps | 99.5% |
| SNPE Vectan Tubal 7000 | <<locked>> | 98% | 45,977 psi | 74% | 2218 fps | 95.2% |
| Somchem S321 | <<locked>> | 80% | 41,611 psi | 67% | 2192 fps | 99.4% |
| Somchem S335 | <<locked>> | 80% | 37,594 psi | 60% | 2057 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 36,376 psi | 58% | 2100 fps | 97% |
| Somchem S355 | <<locked>> | 80% | 29,240 psi | 47% | 1972 fps | 95.3% |
| Somchem S365 | <<locked>> | 88% | 26,919 psi | 43% | 1991 fps | 95.2% |
| Vihtavuori N130 | <<locked>> | 80% | 43,337 psi | 69% | 2110 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 38,276 psi | 61% | 2054 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 33,489 psi | 54% | 2037 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 34,316 psi | 55% | 2041 fps | 99.7% |
| Vihtavuori N150 | <<locked>> | 80% | 27,601 psi | 44% | 1923 fps | 96.2% |
| Vihtavuori N160 | <<locked>> | 92% | 35,955 psi | 58% | 2126 fps | 95.3% |
| Vihtavuori N530 | <<locked>> | 80% | 38,914 psi | 62% | 2123 fps | 98.8% |
| Vihtavuori N540 | <<locked>> | 80% | 32,880 psi | 53% | 2031 fps | 99.2% |
| Vihtavuori N550 | <<locked>> | 94% | 37,217 psi | 60% | 2172 fps | 95.6% |
| Winchester 6.5 StaBALL | <<locked>> | 86% | 30,342 psi | 49% | 1985 fps | 95.2% |
| Winchester 748 | <<locked>> | 80% | 37,608 psi | 60% | 2156 fps | 99.2% |
| Winchester StaBALL Match | <<locked>> | 80% | 34,534 psi | 55% | 2090 fps | 97.3% |
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 100 powders for .338 RCM loaded with the .338 | 250gr | Barnes TSX BT. ReloadSwiss RS 60 delivers the highest muzzle velocity at 2,490 fps; across all powders the maximum-charge window runs from 1,381 fps to 2,490 fps. Accurate 4350 gives the best case fill at 100 %, and 100 of the 100 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (430 MPa), the top charges use 56–90 %, leaving at least 10 % headroom. The 250.0 gr projectile in 0.338" calls for a 1:12.5 twist; slower twists will usually not stabilise this weight. Accurate 4350, Alliant Reloder-16, Alliant Reloder-17 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, ReloadSwiss RS 52, Hodgdon CFE223 rank at the top here: for .338 RCM with the .338 | 250gr | Barnes TSX 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.