Load Specifications
Bullet:.338 | 275gr | Swift A-Frame
Bullet Manufacturer:Swift
Bullet Weight:275 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:1:14.5
Load data in caliber .338 RCM with .338 | 275gr | 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 60, Alliant Power Pro 2000-MR and ReloadSwiss RS 52.
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>> | 86% | 54,230 psi | 87% | 2178 fps | 100% |
| Accurate 2460 | <<locked>> | 84% | 55,985 psi | 90% | 2244 fps | 100% |
| Accurate 2495 | <<locked>> | 92% | 55,288 psi | 89% | 2238 fps | 100% |
| Accurate 2520 | <<locked>> | 86% | 54,099 psi | 87% | 2257 fps | 100% |
| Accurate 2700 | <<locked>> | 92% | 55,492 psi | 89% | 2247 fps | 97.6% |
| Accurate 4064 | <<locked>> | 94% | 54,940 psi | 88% | 2274 fps | 100% |
| Accurate 4350ᴾ | <<locked>> | 100% | 50,459 psi | 81% | 2306 fps | 99.6% |
| ADI AR 2206H | <<locked>> | 90% | 56,318 psi | 90% | 2306 fps | 100% |
| ADI AR 2208 | <<locked>> | 94% | 54,012 psi | 87% | 2267 fps | 99.9% |
| ADI Benchmark 8208 | <<locked>> | 88% | 55,666 psi | 89% | 2267 fps | 100% |
| Alliant AR-Comp | <<locked>> | 88% | 56,115 psi | 90% | 2238 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 82% | 54,186 psi | 87% | 2313 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 92% | 55,782 psi | 89% | 2411 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 94% | 53,417 psi | 86% | 2283 fps | 100% |
| Alliant Reloder-10x | <<locked>> | 82% | 53,911 psi | 86% | 2178 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 92% | 54,302 psi | 87% | 2303 fps | 100% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 49,574 psi | 79% | 2313 fps | 99.7% |
| Alliant Reloder-17 | <<locked>> | 98% | 53,693 psi | 86% | 2385 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 35,099 psi | 56% | 2103 fps | 98.5% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 38,653 psi | 62% | 2224 fps | 97.4% |
| Baschieri & Pellagri 106 | <<locked>> | 82% | 55,695 psi | 89% | 2169 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 90% | 56,115 psi | 90% | 2326 fps | 99.9% |
| Bofors RP3 | <<locked>> | 94% | 53,664 psi | 86% | 2297 fps | 100% |
| Bofors RP7 | <<locked>> | 98% | 54,549 psi | 87% | 2274 fps | 97.8% |
| Hodgdon Benchmark | <<locked>> | 86% | 54,447 psi | 87% | 2215 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 88% | 54,607 psi | 88% | 2297 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 84% | 52,968 psi | 85% | 2336 fps | 100% |
| Hodgdon H322 | <<locked>> | 82% | 52,953 psi | 85% | 2218 fps | 100% |
| Hodgdon H335 | <<locked>> | 82% | 53,882 psi | 86% | 2244 fps | 100% |
| Hodgdon H380 | <<locked>> | 94% | 55,187 psi | 88% | 2310 fps | 99.7% |
| Hodgdon H414ᴾ | <<locked>> | 100% | 53,882 psi | 86% | 2349 fps | 98.4% |
| Hodgdon H4350 | <<locked>> | 98% | 55,347 psi | 89% | 2320 fps | 97.4% |
| Hodgdon H4895 | <<locked>> | 88% | 53,606 psi | 86% | 2277 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 45,571 psi | 73% | 2211 fps | 99.9% |
| Hodgdon LEVERevolution | <<locked>> | 92% | 55,811 psi | 89% | 2346 fps | 100% |
| Hodgdon Superformanceᴾ | <<locked>> | 100% | 54,940 psi | 88% | 2385 fps | 98.1% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,288 psi | 57% | 1335 fps | 100% |
| Hodgdon VARGET | <<locked>> | 90% | 54,882 psi | 88% | 2277 fps | 100% |
| IMR 3031 | <<locked>> | 88% | 53,113 psi | 85% | 2254 fps | 100% |
| IMR 4064 | <<locked>> | 92% | 53,650 psi | 86% | 2254 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 90% | 53,911 psi | 86% | 2238 fps | 98.2% |
| IMR 4198 | <<locked>> | 82% | 54,186 psi | 87% | 2139 fps | 100% |
| IMR 4350ᴾ | <<locked>> | 100% | 51,010 psi | 82% | 2254 fps | 97.3% |
| IMR 4451 Enduron | <<locked>> | 98% | 56,405 psi | 90% | 2300 fps | 98.4% |
| IMR 4831ᴾ | <<locked>> | 100% | 48,066 psi | 77% | 2260 fps | 99.5% |
| IMR 4895 | <<locked>> | 92% | 55,651 psi | 89% | 2329 fps | 100% |
| IMR 8208 XBR | <<locked>> | 88% | 55,666 psi | 89% | 2267 fps | 100% |
| Lovex D073.5 | <<locked>> | 84% | 55,869 psi | 90% | 2257 fps | 100% |
| Lovex D073.6 | <<locked>> | 90% | 55,999 psi | 90% | 2287 fps | 100% |
| Lovex S060 | <<locked>> | 88% | 53,026 psi | 85% | 2208 fps | 100% |
| Lovex S062 | <<locked>> | 92% | 53,200 psi | 85% | 2251 fps | 100% |
| Lovex S065ᴾ | <<locked>> | 100% | 55,259 psi | 89% | 2290 fps | 99.3% |
| Lovex S070ᴾ | <<locked>> | 100% | 52,707 psi | 85% | 2280 fps | 98.3% |
| Norma 201 | <<locked>> | 90% | 55,187 psi | 88% | 2260 fps | 100% |
| Norma 202 | <<locked>> | 90% | 55,753 psi | 89% | 2260 fps | 100% |
| Norma 203B | <<locked>> | 92% | 53,461 psi | 86% | 2293 fps | 100% |
| Norma 204ᴾ | <<locked>> | 100% | 51,126 psi | 82% | 2287 fps | 95.9% |
| Norma URPᴾ | <<locked>> | 100% | 50,212 psi | 81% | 2300 fps | 99.6% |
| Ramshot Big Game | <<locked>> | 92% | 53,635 psi | 86% | 2316 fps | 100% |
| Ramshot Hunterᴾ | <<locked>> | 100% | 49,008 psi | 79% | 2293 fps | 98.3% |
| Ramshot TAC | <<locked>> | 88% | 55,999 psi | 90% | 2290 fps | 99.4% |
| Ramshot Wild Boar | <<locked>> | 88% | 55,201 psi | 89% | 2303 fps | 100% |
| Ramshot X-Terminator | <<locked>> | 84% | 53,374 psi | 86% | 2234 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 35,607 psi | 57% | 1368 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 84% | 55,477 psi | 89% | 2251 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 94% | 55,651 psi | 89% | 2297 fps | 98.9% |
| ReloadSwiss RS 52 | <<locked>> | 90% | 54,520 psi | 87% | 2359 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 96% | 53,563 psi | 86% | 2385 fps | 100% |
| ReloadSwiss RS 62ᴾ | <<locked>> | 100% | 49,908 psi | 80% | 2326 fps | 99.5% |
| ReloadSwiss RS 70ᴾ | <<locked>> | 100% | 50,531 psi | 81% | 2346 fps | 99.3% |
| Rottweil R 901 | <<locked>> | 88% | 56,376 psi | 90% | 2241 fps | 100% |
| Rottweil R 902 | <<locked>> | 92% | 55,767 psi | 89% | 2260 fps | 100% |
| Rottweil R 903 | <<locked>> | 96% | 53,534 psi | 86% | 2287 fps | 100% |
| Rottweil R 907 | <<locked>> | 98% | 54,549 psi | 87% | 2274 fps | 97.8% |
| Shooters World Long Rifleᴾ | <<locked>> | 100% | 55,259 psi | 89% | 2290 fps | 99.3% |
| Shooters World Match Rifle | <<locked>> | 90% | 55,999 psi | 90% | 2287 fps | 100% |
| Shooters World Precision | <<locked>> | 92% | 53,200 psi | 85% | 2251 fps | 100% |
| Shooters World SW4350ᴾ | <<locked>> | 100% | 52,707 psi | 85% | 2280 fps | 98.3% |
| Shooters World Tactical Rifle | <<locked>> | 82% | 54,810 psi | 88% | 2228 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 96% | 55,361 psi | 89% | 2343 fps | 100% |
| SNPE Vectan SP 3 | <<locked>> | 82% | 54,882 psi | 88% | 2195 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 88% | 54,085 psi | 87% | 2270 fps | 99.5% |
| SNPE Vectan SP 9 | <<locked>> | 90% | 54,853 psi | 88% | 2290 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 88% | 53,867 psi | 86% | 2172 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 94% | 53,679 psi | 86% | 2172 fps | 100% |
| SNPE Vectan Tubal 7000ᴾ | <<locked>> | 100% | 56,144 psi | 90% | 2257 fps | 98.4% |
| Somchem S321 | <<locked>> | 84% | 53,156 psi | 85% | 2257 fps | 100% |
| Somchem S335 | <<locked>> | 90% | 56,217 psi | 90% | 2208 fps | 100% |
| Somchem S341 | <<locked>> | 88% | 53,708 psi | 86% | 2264 fps | 100% |
| Somchem S355 | <<locked>> | 96% | 54,201 psi | 87% | 2287 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 44,846 psi | 72% | 2260 fps | 100% |
| Vihtavuori N130 | <<locked>> | 84% | 53,693 psi | 86% | 2139 fps | 100% |
| Vihtavuori N133 | <<locked>> | 88% | 53,998 psi | 87% | 2159 fps | 100% |
| Vihtavuori N135 | <<locked>> | 92% | 55,158 psi | 88% | 2224 fps | 100% |
| Vihtavuori N140 | <<locked>> | 92% | 55,941 psi | 90% | 2241 fps | 100% |
| Vihtavuori N150 | <<locked>> | 98% | 55,419 psi | 89% | 2267 fps | 100% |
| Vihtavuori N160ᴾ | <<locked>> | 100% | 52,591 psi | 84% | 2293 fps | 99.7% |
| Vihtavuori N530 | <<locked>> | 88% | 56,275 psi | 90% | 2267 fps | 100% |
| Vihtavuori N540 | <<locked>> | 92% | 54,056 psi | 87% | 2244 fps | 100% |
| Vihtavuori N550ᴾ | <<locked>> | 100% | 51,750 psi | 83% | 2303 fps | 99.5% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 37,550 psi | 60% | 2162 fps | 98.4% |
| Winchester 6.5 StaBALLᴾ | <<locked>> | 100% | 53,345 psi | 86% | 2280 fps | 100% |
| Winchester 748 | <<locked>> | 88% | 55,564 psi | 89% | 2306 fps | 100% |
| Winchester 760ᴾ | <<locked>> | 100% | 54,157 psi | 87% | 2356 fps | 98.4% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 31,198 psi | 50% | 2093 fps | 98% |
| Winchester StaBALL Match | <<locked>> | 90% | 54,520 psi | 87% | 2297 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% | 45,194 psi | 72% | 2073 fps | 100% |
| Accurate 2460 | <<locked>> | 80% | 49,124 psi | 79% | 2165 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 37,666 psi | 60% | 2018 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 44,251 psi | 71% | 2139 fps | 100% |
| Accurate 2700 | <<locked>> | 84% | 42,801 psi | 69% | 2073 fps | 95% |
| Accurate 4064 | <<locked>> | 80% | 35,650 psi | 57% | 2014 fps | 100% |
| Accurate 4350 | <<locked>> | 84% | 29,312 psi | 47% | 1955 fps | 95% |
| ADI AR 2206H | <<locked>> | 80% | 41,408 psi | 66% | 2103 fps | 99.3% |
| ADI AR 2208 | <<locked>> | 80% | 35,360 psi | 57% | 1988 fps | 97.5% |
| ADI Benchmark 8208 | <<locked>> | 80% | 43,453 psi | 70% | 2110 fps | 99.9% |
| Alliant AR-Comp | <<locked>> | 80% | 43,395 psi | 70% | 2096 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 80% | 50,604 psi | 81% | 2267 fps | 100% |
| Alliant Power Pro 2000-MR | 44.4 gr | 80% | 37,289 psi | 60% | 2126 fps | 97.9% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 34,606 psi | 55% | 2005 fps | 98.8% |
| Alliant Reloder-10x | <<locked>> | 80% | 51,024 psi | 82% | 2146 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 37,260 psi | 60% | 2054 fps | 98.2% |
| Alliant Reloder-16 | <<locked>> | 84% | 30,719 psi | 49% | 1972 fps | 95.2% |
| Alliant Reloder-17 | <<locked>> | 80% | 29,907 psi | 48% | 1982 fps | 96.9% |
| Alliant Reloder-23 | <<locked>> | 92% | 27,702 psi | 44% | 1936 fps | 95.5% |
| Alliant Reloder-26 | <<locked>> | 96% | 33,663 psi | 54% | 2123 fps | 95.5% |
| Baschieri & Pellagri 106 | <<locked>> | 80% | 52,388 psi | 84% | 2133 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 40,350 psi | 65% | 2110 fps | 98.3% |
| Bofors RP3 | <<locked>> | 80% | 34,113 psi | 55% | 2011 fps | 98.8% |
| Bofors RP7 | <<locked>> | 90% | 42,699 psi | 68% | 2110 fps | 95.3% |
| Hodgdon Benchmark | <<locked>> | 80% | 45,469 psi | 73% | 2100 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 41,727 psi | 67% | 2129 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 80% | 46,021 psi | 74% | 2244 fps | 99.6% |
| Hodgdon H322 | <<locked>> | 80% | 49,792 psi | 80% | 2182 fps | 100% |
| Hodgdon H335 | <<locked>> | 80% | 50,459 psi | 81% | 2205 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 34,969 psi | 56% | 2008 fps | 96.3% |
| Hodgdon H414 | <<locked>> | 90% | 39,131 psi | 63% | 2133 fps | 95.2% |
| Hodgdon H4350 | <<locked>> | 92% | 45,759 psi | 73% | 2192 fps | 95.4% |
| Hodgdon H4895 | <<locked>> | 80% | 41,727 psi | 67% | 2113 fps | 99.6% |
| Hodgdon Hybrid 100V | <<locked>> | 82% | 26,353 psi | 42% | 1850 fps | 95.2% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 37,637 psi | 60% | 2093 fps | 99.4% |
| Hodgdon Superformance | <<locked>> | 92% | 41,640 psi | 67% | 2188 fps | 95% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,324 psi | 42% | 1191 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 40,219 psi | 64% | 2077 fps | 99.4% |
| IMR 3031 | <<locked>> | 80% | 41,147 psi | 66% | 2106 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 37,072 psi | 59% | 2014 fps | 98.2% |
| IMR 4166 Enduron | <<locked>> | 80% | 39,523 psi | 63% | 2028 fps | 95% |
| IMR 4198 | <<locked>> | 80% | 51,271 psi | 82% | 2110 fps | 100% |
| IMR 4350 | <<locked>> | 94% | 42,235 psi | 68% | 2126 fps | 95.2% |
| IMR 4451 Enduron | <<locked>> | 88% | 41,698 psi | 67% | 2093 fps | 95.6% |
| IMR 4831 | <<locked>> | 86% | 30,835 psi | 49% | 1972 fps | 95.6% |
| IMR 4895 | <<locked>> | 80% | 38,087 psi | 61% | 2077 fps | 98.8% |
| IMR 8208 XBR | <<locked>> | 80% | 43,453 psi | 70% | 2110 fps | 99.9% |
| Lovex D073.5 | <<locked>> | 80% | 49,008 psi | 79% | 2175 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 40,176 psi | 64% | 2090 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 41,945 psi | 67% | 2054 fps | 99.3% |
| Lovex S062 | <<locked>> | 80% | 36,912 psi | 59% | 2018 fps | 99.4% |
| Lovex S065 | <<locked>> | 86% | 36,390 psi | 58% | 2014 fps | 95.7% |
| Lovex S070 | <<locked>> | 90% | 38,696 psi | 62% | 2073 fps | 95.2% |
| Norma 201 | <<locked>> | 80% | 40,625 psi | 65% | 2067 fps | 99.8% |
| Norma 202 | <<locked>> | 80% | 40,727 psi | 65% | 2070 fps | 100% |
| Norma 203B | <<locked>> | 80% | 36,651 psi | 59% | 2044 fps | 98.5% |
| Norma 204 | <<locked>> | 98% | 48,124 psi | 77% | 2244 fps | 95.2% |
| Norma URP | <<locked>> | 84% | 30,255 psi | 49% | 1962 fps | 95% |
| Ramshot Big Game | <<locked>> | 80% | 35,926 psi | 58% | 2054 fps | 98.2% |
| Ramshot Hunter | <<locked>> | 90% | 35,926 psi | 58% | 2080 fps | 95% |
| Ramshot TAC | <<locked>> | 80% | 43,294 psi | 69% | 2116 fps | 97.7% |
| Ramshot Wild Boar | <<locked>> | 80% | 42,612 psi | 68% | 2133 fps | 99.4% |
| Ramshot X-Terminator | <<locked>> | 80% | 46,833 psi | 75% | 2149 fps | 99.7% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,455 psi | 42% | 1217 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 48,646 psi | 78% | 2172 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 82% | 37,971 psi | 61% | 2041 fps | 95.4% |
| ReloadSwiss RS 52 | 43.1 gr | 80% | 38,696 psi | 62% | 2136 fps | 98.6% |
| ReloadSwiss RS 60 | 43.8 gr | 80% | 31,821 psi | 51% | 2034 fps | 99.5% |
| ReloadSwiss RS 62 | <<locked>> | 86% | 31,444 psi | 50% | 2014 fps | 95.3% |
| ReloadSwiss RS 70 | <<locked>> | 88% | 34,200 psi | 55% | 2067 fps | 95.1% |
| Rottweil R 901 | <<locked>> | 80% | 44,512 psi | 71% | 2093 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 38,696 psi | 62% | 2028 fps | 99.6% |
| Rottweil R 903 | <<locked>> | 80% | 32,140 psi | 52% | 1965 fps | 98% |
| Rottweil R 907 | <<locked>> | 90% | 42,699 psi | 68% | 2110 fps | 95.3% |
| Shooters World Long Rifle | <<locked>> | 86% | 36,390 psi | 58% | 2014 fps | 95.7% |
| Shooters World Match Rifle | <<locked>> | 80% | 40,176 psi | 64% | 2090 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 36,912 psi | 59% | 2018 fps | 99.4% |
| Shooters World SW4350 | <<locked>> | 90% | 38,696 psi | 62% | 2073 fps | 95.2% |
| Shooters World Tactical Rifle | <<locked>> | 80% | 51,300 psi | 82% | 2185 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 33,098 psi | 53% | 2005 fps | 97.5% |
| SNPE Vectan SP 3 | <<locked>> | 80% | 51,532 psi | 83% | 2159 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 41,495 psi | 67% | 2096 fps | 97.9% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 39,972 psi | 64% | 2083 fps | 99% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 42,119 psi | 68% | 2024 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 34,795 psi | 56% | 1923 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 90% | 40,219 psi | 64% | 2047 fps | 95.4% |
| Somchem S321 | <<locked>> | 80% | 46,717 psi | 75% | 2175 fps | 100% |
| Somchem S335 | <<locked>> | 80% | 41,713 psi | 67% | 2031 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 41,118 psi | 66% | 2093 fps | 99.1% |
| Somchem S355 | <<locked>> | 80% | 33,054 psi | 53% | 1969 fps | 98.1% |
| Somchem S365 | <<locked>> | 80% | 23,975 psi | 38% | 1837 fps | 95.6% |
| Vihtavuori N130 | <<locked>> | 80% | 47,616 psi | 76% | 2070 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 42,337 psi | 68% | 2018 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 37,826 psi | 61% | 2011 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 38,725 psi | 62% | 2024 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 31,459 psi | 50% | 1923 fps | 98.7% |
| Vihtavuori N160 | <<locked>> | 84% | 31,676 psi | 51% | 1962 fps | 95.5% |
| Vihtavuori N530 | <<locked>> | 80% | 43,540 psi | 70% | 2106 fps | 99.9% |
| Vihtavuori N540 | <<locked>> | 80% | 37,043 psi | 59% | 2014 fps | 100% |
| Vihtavuori N550 | <<locked>> | 84% | 31,067 psi | 50% | 1969 fps | 95.1% |
| Vihtavuori N555 | <<locked>> | 92% | 29,225 psi | 47% | 1995 fps | 95.6% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 27,978 psi | 45% | 1864 fps | 96.1% |
| Winchester 748 | <<locked>> | 80% | 42,786 psi | 69% | 2146 fps | 100% |
| Winchester 760 | <<locked>> | 90% | 39,131 psi | 63% | 2133 fps | 95.2% |
| Winchester StaBALL HD | <<locked>> | 96% | 27,688 psi | 44% | 1995 fps | 95.8% |
| Winchester StaBALL Match | <<locked>> | 80% | 39,218 psi | 63% | 2087 fps | 99.3% |
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 106 powders for .338 RCM loaded with the .338 | 275gr | Swift A-Frame. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 2,411 fps; across all powders the maximum-charge window runs from 1,335 fps to 2,411 fps. Accurate 4350 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 50–90 %, leaving at least 10 % headroom. The 275.0 gr projectile in 0.338" calls for a 1:14.5 twist; slower twists will usually not stabilise this weight. Accurate 4350, Alliant Reloder-16, Alliant Reloder-23 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 60, Alliant Power Pro 2000-MR, ReloadSwiss RS 52 rank at the top here: for .338 RCM with the .338 | 275gr | 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.