Load Specifications
Load data in caliber .338 Win Mag. with .338 | 300gr | Woodleigh RN SN bullet and 95 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Alliant Reloder-26, ReloadSwiss RS 70 and Hodgdon Superformance.
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 2495 | <<locked>> | 82% | 55,114 psi | 88% | 2205 fps | 100% |
| Accurate 2700 | <<locked>> | 84% | 56,144 psi | 90% | 2274 fps | 99.7% |
| Accurate 3100ᴾ | <<locked>> | 100% | 53,200 psi | 85% | 2320 fps | 100% |
| Accurate 4064 | <<locked>> | 84% | 55,550 psi | 89% | 2251 fps | 100% |
| Accurate 4350 | <<locked>> | 92% | 55,680 psi | 89% | 2352 fps | 100% |
| Accurate MAGPROᴾ | <<locked>> | 100% | 55,187 psi | 88% | 2448 fps | 97.9% |
| ADI AR 2208 | <<locked>> | 86% | 55,347 psi | 89% | 2280 fps | 100% |
| ADI AR 2209 | <<locked>> | 96% | 52,939 psi | 85% | 2352 fps | 99.1% |
| ADI AR 2213ᴾ | <<locked>> | 100% | 54,012 psi | 87% | 2395 fps | 98.4% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 34,780 psi | 56% | 2129 fps | 96.8% |
| Alliant Power Pro 2000-MR | <<locked>> | 82% | 54,592 psi | 88% | 2388 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 86% | 56,260 psi | 90% | 2300 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 82% | 53,171 psi | 85% | 2280 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 94% | 56,405 psi | 90% | 2395 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 88% | 53,925 psi | 86% | 2372 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 98% | 55,811 psi | 89% | 2388 fps | 99.4% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 52,808 psi | 85% | 2395 fps | 99.3% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 50,067 psi | 80% | 2333 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 43,642 psi | 70% | 2287 fps | 99.9% |
| Alliant Reloder-26 | <<locked>> | 98% | 53,098 psi | 85% | 2448 fps | 100% |
| Bofors RP15ᴾ | <<locked>> | 100% | 48,559 psi | 78% | 2336 fps | 98.7% |
| Bofors RP3 | <<locked>> | 84% | 53,548 psi | 86% | 2274 fps | 100% |
| Bofors RP30ᴾ | <<locked>> | 100% | 39,436 psi | 63% | 2221 fps | 96% |
| Bofors RP5ᴾ | <<locked>> | 100% | 52,808 psi | 85% | 2395 fps | 99.3% |
| Bofors RP7 | <<locked>> | 90% | 56,217 psi | 90% | 2310 fps | 99.8% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 43,395 psi | 70% | 2234 fps | 96.9% |
| Hodgdon H380 | <<locked>> | 84% | 53,896 psi | 86% | 2290 fps | 100% |
| Hodgdon H414 | <<locked>> | 90% | 54,389 psi | 87% | 2356 fps | 99.9% |
| Hodgdon H4350 | <<locked>> | 88% | 54,215 psi | 87% | 2320 fps | 99.4% |
| Hodgdon H4831 | <<locked>> | 98% | 54,244 psi | 87% | 2349 fps | 97.9% |
| Hodgdon H4831 SC | <<locked>> | 98% | 53,142 psi | 85% | 2336 fps | 97.7% |
| Hodgdon Hybrid 100V | <<locked>> | 94% | 53,243 psi | 85% | 2290 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 82% | 55,172 psi | 88% | 2316 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 42,699 psi | 68% | 2320 fps | 98.3% |
| Hodgdon Superformance | <<locked>> | 90% | 54,201 psi | 87% | 2392 fps | 99.8% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,521 psi | 59% | 1385 fps | 100% |
| Hodgdon VARGET | <<locked>> | 82% | 55,898 psi | 90% | 2280 fps | 100% |
| IMR 4064 | <<locked>> | 84% | 54,824 psi | 88% | 2264 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 82% | 54,056 psi | 87% | 2257 fps | 99.8% |
| IMR 4350 | <<locked>> | 92% | 53,664 psi | 86% | 2300 fps | 99.7% |
| IMR 4451 Enduron | <<locked>> | 88% | 54,505 psi | 87% | 2290 fps | 99.8% |
| IMR 4831 | <<locked>> | 94% | 56,231 psi | 90% | 2346 fps | 100% |
| IMR 4895 | <<locked>> | 82% | 54,563 psi | 87% | 2300 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 98% | 55,883 psi | 90% | 2336 fps | 98.2% |
| IMR 7828 SSCᴾ | <<locked>> | 100% | 51,576 psi | 83% | 2375 fps | 98.1% |
| Lovex S062 | <<locked>> | 84% | 55,274 psi | 89% | 2260 fps | 100% |
| Lovex S065 | <<locked>> | 90% | 54,491 psi | 87% | 2287 fps | 100% |
| Lovex S070 | <<locked>> | 92% | 55,796 psi | 89% | 2323 fps | 100% |
| Lovex S071ᴾ | <<locked>> | 100% | 44,324 psi | 71% | 2201 fps | 99.5% |
| Norma 203B | <<locked>> | 84% | 55,782 psi | 89% | 2310 fps | 100% |
| Norma 204 | <<locked>> | 92% | 54,128 psi | 87% | 2346 fps | 99.1% |
| Norma MRPᴾ | <<locked>> | 100% | 56,130 psi | 90% | 2464 fps | 100% |
| Norma URP | <<locked>> | 92% | 54,563 psi | 87% | 2339 fps | 100% |
| Ramshot Big Game | <<locked>> | 84% | 56,420 psi | 90% | 2333 fps | 100% |
| Ramshot Grandᴾ | <<locked>> | 100% | 51,750 psi | 83% | 2388 fps | 98.5% |
| Ramshot Hunter | <<locked>> | 92% | 53,113 psi | 85% | 2346 fps | 100% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 46,093 psi | 74% | 2290 fps | 98.8% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,144 psi | 60% | 1414 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 84% | 53,737 psi | 86% | 2280 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 86% | 53,737 psi | 86% | 2362 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 92% | 55,376 psi | 89% | 2372 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 92% | 53,925 psi | 86% | 2402 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 42,206 psi | 68% | 2310 fps | 99% |
| Rottweil R 902 | <<locked>> | 82% | 53,795 psi | 86% | 2228 fps | 100% |
| Rottweil R 903 | <<locked>> | 86% | 53,679 psi | 86% | 2274 fps | 100% |
| Rottweil R 904 | <<locked>> | 96% | 54,839 psi | 88% | 2326 fps | 98.5% |
| Rottweil R 905 | <<locked>> | 98% | 55,042 psi | 88% | 2375 fps | 99.4% |
| Rottweil R 907 | <<locked>> | 90% | 56,217 psi | 90% | 2310 fps | 99.8% |
| Shooters World Long Rifle | <<locked>> | 90% | 54,491 psi | 87% | 2287 fps | 100% |
| Shooters World Precision | <<locked>> | 84% | 55,274 psi | 89% | 2260 fps | 100% |
| Shooters World SW4350 | <<locked>> | 92% | 55,796 psi | 89% | 2323 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 86% | 54,897 psi | 88% | 2320 fps | 100% |
| SNPE Vectan SP 9 | <<locked>> | 82% | 56,086 psi | 90% | 2293 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 86% | 54,723 psi | 88% | 2169 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 90% | 54,259 psi | 87% | 2251 fps | 99.8% |
| SNPE Vectan Tubal 8000 | <<locked>> | 98% | 54,563 psi | 87% | 2372 fps | 99.4% |
| Somchem S355 | <<locked>> | 86% | 53,722 psi | 86% | 2267 fps | 100% |
| Somchem S361 | <<locked>> | 96% | 56,362 psi | 90% | 2323 fps | 98.1% |
| Somchem S365 | <<locked>> | 94% | 53,563 psi | 86% | 2339 fps | 100% |
| Somchem S385 | <<locked>> | 98% | 55,666 psi | 89% | 2356 fps | 99.8% |
| Vihtavuori N135 | <<locked>> | 82% | 54,186 psi | 87% | 2188 fps | 100% |
| Vihtavuori N140 | <<locked>> | 82% | 54,404 psi | 87% | 2205 fps | 100% |
| Vihtavuori N150 | <<locked>> | 88% | 54,795 psi | 88% | 2247 fps | 100% |
| Vihtavuori N160 | <<locked>> | 90% | 53,098 psi | 85% | 2290 fps | 100% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 51,314 psi | 82% | 2290 fps | 99.2% |
| Vihtavuori N540 | <<locked>> | 84% | 55,825 psi | 90% | 2244 fps | 100% |
| Vihtavuori N550 | <<locked>> | 92% | 55,695 psi | 89% | 2343 fps | 100% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 55,999 psi | 90% | 2392 fps | 100% |
| Vihtavuori N560 | <<locked>> | 98% | 52,779 psi | 85% | 2408 fps | 98% |
| Vihtavuori N565ᴾ | <<locked>> | 100% | 44,802 psi | 72% | 2290 fps | 96.7% |
| Winchester 6.5 StaBALL | <<locked>> | 92% | 56,115 psi | 90% | 2306 fps | 100% |
| Winchester 760 | <<locked>> | 90% | 54,389 psi | 87% | 2356 fps | 99.9% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 45,121 psi | 72% | 2392 fps | 100% |
| Winchester StaBALL Match | <<locked>> | 82% | 56,289 psi | 90% | 2303 fps | 100% |
| Winchester Supreme 780ᴾ | <<locked>> | 100% | 55,724 psi | 89% | 2352 fps | 99.3% |
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% | 51,706 psi | 83% | 2165 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 49,255 psi | 79% | 2185 fps | 99.1% |
| Accurate 3100 | <<locked>> | 80% | 27,340 psi | 44% | 1886 fps | 95.1% |
| Accurate 4064 | <<locked>> | 80% | 49,008 psi | 79% | 2175 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 37,246 psi | 60% | 2090 fps | 99.5% |
| Accurate MAGPRO | <<locked>> | 94% | 44,846 psi | 72% | 2297 fps | 95.7% |
| ADI AR 2208 | <<locked>> | 80% | 46,238 psi | 74% | 2162 fps | 100% |
| ADI AR 2209 | <<locked>> | 84% | 36,260 psi | 58% | 2080 fps | 95.4% |
| ADI AR 2213 | <<locked>> | 92% | 41,684 psi | 67% | 2205 fps | 95.6% |
| ADI AR 2225 | <<locked>> | 98% | 32,735 psi | 52% | 2083 fps | 95.8% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 50,937 psi | 82% | 2343 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 46,775 psi | 75% | 2182 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 49,748 psi | 80% | 2234 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 36,506 psi | 59% | 2100 fps | 99.6% |
| Alliant Reloder-17 | <<locked>> | 80% | 41,060 psi | 66% | 2195 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 84% | 36,013 psi | 58% | 2077 fps | 95.5% |
| Alliant Reloder-22 | <<locked>> | 88% | 35,766 psi | 57% | 2116 fps | 95.6% |
| Alliant Reloder-23 | <<locked>> | 80% | 26,745 psi | 43% | 1916 fps | 98.4% |
| Alliant Reloder-25 | <<locked>> | 86% | 28,326 psi | 45% | 1969 fps | 95.9% |
| Alliant Reloder-26 | 56.7 gr | 80% | 28,297 psi | 45% | 2008 fps | 97% |
| Bofors RP15 | <<locked>> | 90% | 35,491 psi | 57% | 2110 fps | 95.3% |
| Bofors RP3 | <<locked>> | 80% | 46,920 psi | 75% | 2192 fps | 100% |
| Bofors RP30 | <<locked>> | 98% | 37,043 psi | 59% | 2175 fps | 95.1% |
| Bofors RP5 | <<locked>> | 88% | 35,766 psi | 57% | 2116 fps | 95.6% |
| Bofors RP7 | <<locked>> | 80% | 41,510 psi | 67% | 2100 fps | 98% |
| Hodgdon H1000 | <<locked>> | 96% | 38,014 psi | 61% | 2136 fps | 95.1% |
| Hodgdon H380 | <<locked>> | 80% | 47,340 psi | 76% | 2205 fps | 100% |
| Hodgdon H414 | <<locked>> | 80% | 39,175 psi | 63% | 2129 fps | 98.1% |
| Hodgdon H4350 | <<locked>> | 80% | 42,192 psi | 68% | 2142 fps | 97.6% |
| Hodgdon H4831 | <<locked>> | 90% | 41,829 psi | 67% | 2165 fps | 95% |
| Hodgdon H4831 SC | <<locked>> | 92% | 43,714 psi | 70% | 2198 fps | 95.6% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 33,982 psi | 54% | 2011 fps | 99.8% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 51,590 psi | 83% | 2274 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 94% | 35,389 psi | 57% | 2169 fps | 95.8% |
| Hodgdon Superformance | 58.5 gr | 80% | 38,029 psi | 61% | 2142 fps | 97.5% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,398 psi | 44% | 1234 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 52,576 psi | 84% | 2241 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 48,631 psi | 78% | 2185 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 80% | 50,894 psi | 82% | 2215 fps | 99.6% |
| IMR 4350 | <<locked>> | 80% | 36,999 psi | 59% | 2044 fps | 96.9% |
| IMR 4451 Enduron | <<locked>> | 80% | 42,786 psi | 69% | 2123 fps | 98.6% |
| IMR 4831 | <<locked>> | 80% | 35,926 psi | 58% | 2054 fps | 99.3% |
| IMR 4895 | <<locked>> | 80% | 51,039 psi | 82% | 2257 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 88% | 41,234 psi | 66% | 2123 fps | 95.1% |
| IMR 7828 SSC | <<locked>> | 92% | 39,769 psi | 64% | 2185 fps | 95.1% |
| Lovex S062 | <<locked>> | 80% | 48,878 psi | 78% | 2182 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 40,364 psi | 65% | 2083 fps | 99.1% |
| Lovex S070 | <<locked>> | 80% | 38,653 psi | 62% | 2073 fps | 98.1% |
| Lovex S071 | <<locked>> | 86% | 28,616 psi | 46% | 1916 fps | 95.7% |
| Norma 203B | <<locked>> | 80% | 49,110 psi | 79% | 2224 fps | 100% |
| Norma 204 | <<locked>> | 80% | 36,448 psi | 58% | 2067 fps | 95.4% |
| Norma MRP | <<locked>> | 82% | 30,632 psi | 49% | 2031 fps | 95% |
| Norma URP | <<locked>> | 80% | 37,231 psi | 60% | 2087 fps | 99.4% |
| Ramshot Big Game | <<locked>> | 80% | 49,443 psi | 79% | 2247 fps | 100% |
| Ramshot Grand | <<locked>> | 92% | 39,363 psi | 63% | 2188 fps | 95.4% |
| Ramshot Hunter | <<locked>> | 80% | 35,984 psi | 58% | 2083 fps | 98.1% |
| Ramshot Magnum | <<locked>> | 92% | 34,751 psi | 56% | 2090 fps | 95.8% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,833 psi | 45% | 1263 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 47,384 psi | 76% | 2195 fps | 99.6% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 43,613 psi | 70% | 2234 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 37,014 psi | 59% | 2110 fps | 99.3% |
| ReloadSwiss RS 70 | 56.2 gr | 80% | 35,911 psi | 58% | 2119 fps | 99% |
| ReloadSwiss RS 76 | <<locked>> | 92% | 32,314 psi | 52% | 2100 fps | 95.5% |
| Rottweil R 902 | <<locked>> | 80% | 50,604 psi | 81% | 2188 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 44,353 psi | 71% | 2152 fps | 100% |
| Rottweil R 904 | <<locked>> | 86% | 40,132 psi | 64% | 2106 fps | 95.4% |
| Rottweil R 905 | <<locked>> | 84% | 34,998 psi | 56% | 2064 fps | 95.4% |
| Rottweil R 907 | <<locked>> | 80% | 41,510 psi | 67% | 2100 fps | 98% |
| Shooters World Long Rifle | <<locked>> | 80% | 40,364 psi | 65% | 2083 fps | 99.1% |
| Shooters World Precision | <<locked>> | 80% | 48,878 psi | 78% | 2182 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 38,653 psi | 62% | 2073 fps | 98.1% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 45,411 psi | 73% | 2198 fps | 100% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 52,823 psi | 85% | 2254 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 45,687 psi | 73% | 2064 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 39,363 psi | 63% | 2037 fps | 98% |
| SNPE Vectan Tubal 8000 | <<locked>> | 84% | 34,708 psi | 56% | 2060 fps | 95.3% |
| Somchem S355 | <<locked>> | 80% | 44,643 psi | 72% | 2149 fps | 100% |
| Somchem S361 | <<locked>> | 88% | 43,482 psi | 70% | 2146 fps | 95.4% |
| Somchem S365 | <<locked>> | 80% | 33,533 psi | 54% | 2054 fps | 100% |
| Somchem S385 | <<locked>> | 82% | 33,257 psi | 53% | 2005 fps | 95.7% |
| Vihtavuori N135 | <<locked>> | 80% | 51,097 psi | 82% | 2152 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 51,140 psi | 82% | 2169 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 42,641 psi | 68% | 2093 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 38,479 psi | 62% | 2080 fps | 99.5% |
| Vihtavuori N165 | <<locked>> | 86% | 32,779 psi | 53% | 1991 fps | 95% |
| Vihtavuori N540 | <<locked>> | 80% | 49,240 psi | 79% | 2169 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 37,985 psi | 61% | 2090 fps | 99.4% |
| Vihtavuori N555 | <<locked>> | 80% | 29,399 psi | 47% | 1975 fps | 98.4% |
| Vihtavuori N560 | <<locked>> | 90% | 40,538 psi | 65% | 2215 fps | 95% |
| Vihtavuori N565 | <<locked>> | 96% | 39,204 psi | 63% | 2195 fps | 95.1% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 37,405 psi | 60% | 2057 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 39,392 psi | 63% | 2133 fps | 98.2% |
| Winchester StaBALL HD | <<locked>> | 80% | 23,598 psi | 38% | 1906 fps | 97.8% |
| Winchester StaBALL Match | <<locked>> | 80% | 52,678 psi | 84% | 2260 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 86% | 34,751 psi | 56% | 2034 fps | 95% |
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 Win Mag. loaded with the .338 | 300gr | Woodleigh RN SN. Norma MRP delivers the highest muzzle velocity at 2,464 fps; across all powders the maximum-charge window runs from 1,385 fps to 2,464 fps. Accurate 3100 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 49–90 %, leaving at least 10 % headroom. The 300.0 gr projectile in 0.338" calls for a 1:15.5 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. Alliant Reloder-26, ReloadSwiss RS 70, Hodgdon Superformance rank at the top here: for .338 Win Mag. with the .338 | 300gr | Woodleigh RN SN they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, ADI AR 2217, Norma 217, ReloadSwiss RS 80 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.