Load Specifications
Bullet Manufacturer:Sierra
Bullet Weight:250 gr
Bullet Diameter:0.338"
Bullet Length:<<locked>>
Caliber:.338-06 A-Square load data
Case Length (l3):2.494"
Cartridge Length (C.O.L.):<<locked>>
Case Capacity:69 Grains of Water
Primer Size:Large Rifle (LR)
Barrel Length:24"
Max. allowed Pressure:63,091 psi
Recommended Twist Rate:1:14.0
Load data in caliber .338-06 A-Square with .338 | 250gr | Sierra GameKing bullet and 105 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.
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>> | 90% | 55,825 psi | 88% | 2297 fps | 100% |
| Accurate 2200 | <<locked>> | 82% | 55,912 psi | 89% | 2382 fps | 99.5% |
| Accurate 2230 | <<locked>> | 82% | 56,855 psi | 90% | 2395 fps | 99.7% |
| Accurate 2460 | <<locked>> | 86% | 54,114 psi | 86% | 2323 fps | 100% |
| Accurate 2495 | <<locked>> | 96% | 56,333 psi | 89% | 2352 fps | 100% |
| Accurate 2520 | <<locked>> | 90% | 55,651 psi | 88% | 2375 fps | 100% |
| Accurate 2700 | <<locked>> | 94% | 53,751 psi | 85% | 2306 fps | 95.8% |
| Accurate 4064 | <<locked>> | 98% | 55,825 psi | 88% | 2388 fps | 100% |
| Accurate 4350ᴾ | <<locked>> | 100% | 44,353 psi | 70% | 2313 fps | 97.9% |
| Accurate LT-30 | <<locked>> | 84% | 55,695 psi | 88% | 2251 fps | 100% |
| Accurate LT-32 | <<locked>> | 84% | 56,173 psi | 89% | 2270 fps | 100% |
| ADI AR 2206H | <<locked>> | 92% | 54,578 psi | 87% | 2382 fps | 99.8% |
| ADI AR 2208 | <<locked>> | 98% | 55,390 psi | 88% | 2375 fps | 99.6% |
| ADI AR 2219 | <<locked>> | 84% | 56,260 psi | 89% | 2356 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 90% | 54,070 psi | 86% | 2343 fps | 100% |
| Alliant AR-Comp | <<locked>> | 92% | 56,927 psi | 90% | 2356 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 86% | 55,506 psi | 88% | 2428 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 94% | 53,577 psi | 85% | 2474 fps | 99.5% |
| Alliant Reloder- TS 15.5 | <<locked>> | 98% | 54,302 psi | 86% | 2392 fps | 100% |
| Alliant Reloder-10x | <<locked>> | 86% | 55,550 psi | 88% | 2300 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 96% | 55,303 psi | 88% | 2411 fps | 99.7% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 44,599 psi | 71% | 2316 fps | 98% |
| Alliant Reloder-17ᴾ | <<locked>> | 100% | 51,445 psi | 82% | 2448 fps | 99.9% |
| Baschieri & Pellagri 106 | <<locked>> | 84% | 54,752 psi | 87% | 2254 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 92% | 53,882 psi | 85% | 2392 fps | 99.3% |
| Bofors RP3 | <<locked>> | 98% | 54,766 psi | 87% | 2405 fps | 100% |
| Bofors RP7ᴾ | <<locked>> | 100% | 52,359 psi | 83% | 2329 fps | 95.9% |
| Hodgdon Benchmark | <<locked>> | 90% | 56,376 psi | 89% | 2329 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 92% | 55,898 psi | 89% | 2411 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 88% | 54,230 psi | 86% | 2448 fps | 99.6% |
| Hodgdon H322 | <<locked>> | 86% | 54,868 psi | 87% | 2339 fps | 100% |
| Hodgdon H335 | <<locked>> | 86% | 55,651 psi | 88% | 2365 fps | 100% |
| Hodgdon H380 | <<locked>> | 98% | 56,347 psi | 89% | 2415 fps | 99.1% |
| Hodgdon H414ᴾ | <<locked>> | 100% | 48,051 psi | 76% | 2356 fps | 95.8% |
| Hodgdon H4895 | <<locked>> | 92% | 55,013 psi | 87% | 2388 fps | 99.9% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 40,843 psi | 65% | 2221 fps | 98.5% |
| Hodgdon LEVERevolution | <<locked>> | 96% | 56,942 psi | 90% | 2457 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 34,664 psi | 55% | 1381 fps | 100% |
| Hodgdon VARGET | <<locked>> | 94% | 56,304 psi | 89% | 2388 fps | 100% |
| IMR 3031 | <<locked>> | 92% | 54,172 psi | 86% | 2372 fps | 100% |
| IMR 4064 | <<locked>> | 96% | 54,940 psi | 87% | 2359 fps | 99.6% |
| IMR 4166 Enduron | <<locked>> | 94% | 55,970 psi | 89% | 2346 fps | 97.1% |
| IMR 4198 | <<locked>> | 86% | 56,231 psi | 89% | 2264 fps | 100% |
| IMR 4451 Enduronᴾ | <<locked>> | 100% | 54,389 psi | 86% | 2356 fps | 96.8% |
| IMR 4831ᴾ | <<locked>> | 100% | 42,409 psi | 67% | 2264 fps | 97.5% |
| IMR 4895 | <<locked>> | 96% | 56,681 psi | 90% | 2438 fps | 99.9% |
| IMR 8208 XBR | <<locked>> | 90% | 54,070 psi | 86% | 2343 fps | 100% |
| Lovex D073.5 | <<locked>> | 86% | 53,925 psi | 85% | 2333 fps | 100% |
| Lovex D073.6 | <<locked>> | 92% | 53,374 psi | 85% | 2359 fps | 100% |
| Lovex S060 | <<locked>> | 92% | 54,955 psi | 87% | 2320 fps | 99.8% |
| Lovex S062 | <<locked>> | 96% | 54,259 psi | 86% | 2359 fps | 100% |
| Lovex S065ᴾ | <<locked>> | 100% | 49,763 psi | 79% | 2306 fps | 97.4% |
| Lovex S070ᴾ | <<locked>> | 100% | 47,239 psi | 75% | 2287 fps | 95.8% |
| Norma 200 | <<locked>> | 82% | 55,767 psi | 88% | 2277 fps | 100% |
| Norma 201 | <<locked>> | 94% | 56,782 psi | 90% | 2375 fps | 100% |
| Norma 202 | <<locked>> | 94% | 56,884 psi | 90% | 2375 fps | 100% |
| Norma 203B | <<locked>> | 96% | 54,433 psi | 86% | 2402 fps | 99.8% |
| Norma URPᴾ | <<locked>> | 100% | 44,570 psi | 71% | 2306 fps | 97.8% |
| Ramshot Big Game | <<locked>> | 96% | 54,708 psi | 87% | 2425 fps | 99.8% |
| Ramshot TAC | <<locked>> | 90% | 54,549 psi | 86% | 2359 fps | 98.3% |
| Ramshot Wild Boar | <<locked>> | 92% | 57,000 psi | 90% | 2418 fps | 99.9% |
| Ramshot X-Terminator | <<locked>> | 88% | 55,390 psi | 88% | 2349 fps | 99.7% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 34,882 psi | 55% | 1414 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 86% | 53,838 psi | 85% | 2329 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 96% | 53,621 psi | 85% | 2356 fps | 97.4% |
| ReloadSwiss RS 52 | <<locked>> | 94% | 55,303 psi | 88% | 2467 fps | 99.7% |
| ReloadSwiss RS 60ᴾ | <<locked>> | 100% | 54,940 psi | 87% | 2497 fps | 100% |
| ReloadSwiss RS 62ᴾ | <<locked>> | 100% | 44,106 psi | 70% | 2329 fps | 97.5% |
| ReloadSwiss RS 70ᴾ | <<locked>> | 100% | 45,498 psi | 72% | 2346 fps | 96.9% |
| Rottweil R 901 | <<locked>> | 90% | 54,665 psi | 87% | 2323 fps | 100% |
| Rottweil R 902 | <<locked>> | 96% | 57,058 psi | 90% | 2372 fps | 100% |
| Rottweil R 903ᴾ | <<locked>> | 100% | 54,244 psi | 86% | 2392 fps | 99.9% |
| Rottweil R 907ᴾ | <<locked>> | 100% | 52,359 psi | 83% | 2329 fps | 95.9% |
| Shooters World Long Rifleᴾ | <<locked>> | 100% | 49,763 psi | 79% | 2306 fps | 97.4% |
| Shooters World Match Rifle | <<locked>> | 92% | 53,374 psi | 85% | 2359 fps | 100% |
| Shooters World Precision | <<locked>> | 96% | 54,259 psi | 86% | 2359 fps | 100% |
| Shooters World SW4350ᴾ | <<locked>> | 100% | 47,239 psi | 75% | 2287 fps | 95.8% |
| Shooters World Tactical Rifle | <<locked>> | 84% | 53,679 psi | 85% | 2303 fps | 99.9% |
| SNPE Vectan BA6 1/2 | <<locked>> | 82% | 56,449 psi | 89% | 2034 fps | 100% |
| SNPE Vectan SP 10 | <<locked>> | 84% | 56,420 psi | 89% | 2365 fps | 100% |
| SNPE Vectan SP 11ᴾ | <<locked>> | 100% | 56,202 psi | 89% | 2448 fps | 99.9% |
| SNPE Vectan SP 3 | <<locked>> | 86% | 56,594 psi | 90% | 2316 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 92% | 55,956 psi | 89% | 2382 fps | 98.9% |
| SNPE Vectan SP 9 | <<locked>> | 94% | 56,391 psi | 89% | 2402 fps | 99.9% |
| SNPE Vectan Tubal 3000 | <<locked>> | 92% | 55,550 psi | 88% | 2283 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 98% | 54,882 psi | 87% | 2280 fps | 100% |
| SNPE Vectan Tubal 7000ᴾ | <<locked>> | 100% | 50,198 psi | 80% | 2270 fps | 96.1% |
| Somchem S321 | <<locked>> | 88% | 55,230 psi | 88% | 2375 fps | 100% |
| Somchem S335 | <<locked>> | 92% | 54,650 psi | 87% | 2287 fps | 100% |
| Somchem S341 | <<locked>> | 92% | 55,172 psi | 87% | 2372 fps | 99.8% |
| Somchem S355ᴾ | <<locked>> | 100% | 54,882 psi | 87% | 2392 fps | 99.9% |
| Somchem S365ᴾ | <<locked>> | 100% | 39,711 psi | 63% | 2267 fps | 99.4% |
| Vihtavuori N130 | <<locked>> | 88% | 55,579 psi | 88% | 2257 fps | 100% |
| Vihtavuori N133 | <<locked>> | 92% | 55,463 psi | 88% | 2270 fps | 100% |
| Vihtavuori N135 | <<locked>> | 96% | 56,057 psi | 89% | 2339 fps | 100% |
| Vihtavuori N140 | <<locked>> | 94% | 54,056 psi | 86% | 2320 fps | 100% |
| Vihtavuori N150ᴾ | <<locked>> | 100% | 53,185 psi | 84% | 2336 fps | 100% |
| Vihtavuori N160ᴾ | <<locked>> | 100% | 47,137 psi | 75% | 2310 fps | 98.1% |
| Vihtavuori N530 | <<locked>> | 90% | 54,636 psi | 87% | 2343 fps | 100% |
| Vihtavuori N540 | <<locked>> | 96% | 55,564 psi | 88% | 2359 fps | 100% |
| Vihtavuori N550ᴾ | <<locked>> | 100% | 46,050 psi | 73% | 2313 fps | 97.8% |
| Winchester 6.5 StaBALLᴾ | <<locked>> | 100% | 48,037 psi | 76% | 2297 fps | 99.5% |
| Winchester 748 | <<locked>> | 90% | 53,461 psi | 85% | 2382 fps | 100% |
| Winchester 760ᴾ | <<locked>> | 100% | 48,051 psi | 76% | 2356 fps | 95.8% |
| Winchester StaBALL Match | <<locked>> | 94% | 55,869 psi | 89% | 2408 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% | 41,104 psi | 65% | 2113 fps | 100% |
| Accurate 2200 | <<locked>> | 80% | 52,504 psi | 83% | 2336 fps | 99.2% |
| Accurate 2230 | <<locked>> | 80% | 52,997 psi | 84% | 2346 fps | 99.5% |
| Accurate 2460 | <<locked>> | 80% | 44,382 psi | 70% | 2198 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 33,547 psi | 53% | 2044 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 39,682 psi | 63% | 2162 fps | 99.8% |
| Accurate 2700 | <<locked>> | 92% | 50,285 psi | 80% | 2260 fps | 95% |
| Accurate 4064 | <<locked>> | 80% | 31,763 psi | 50% | 2034 fps | 99.4% |
| Accurate 4350 | <<locked>> | 94% | 35,984 psi | 57% | 2172 fps | 95.7% |
| Accurate LT-30 | <<locked>> | 80% | 49,269 psi | 78% | 2175 fps | 100% |
| Accurate LT-32 | <<locked>> | 80% | 49,661 psi | 79% | 2192 fps | 100% |
| ADI AR 2206H | <<locked>> | 80% | 37,492 psi | 59% | 2119 fps | 97.4% |
| ADI AR 2208 | <<locked>> | 82% | 34,055 psi | 54% | 2041 fps | 95.5% |
| ADI AR 2219 | <<locked>> | 80% | 49,255 psi | 78% | 2274 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 80% | 39,450 psi | 63% | 2129 fps | 98.8% |
| Alliant AR-Comp | <<locked>> | 80% | 38,479 psi | 61% | 2133 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 80% | 45,571 psi | 72% | 2293 fps | 99.4% |
| Alliant Power Pro 2000-MR | 44.6 gr | 82% | 36,100 psi | 57% | 2175 fps | 95.7% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 31,038 psi | 49% | 2014 fps | 96.5% |
| Alliant Reloder-10x | <<locked>> | 80% | 46,325 psi | 73% | 2188 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 33,475 psi | 53% | 2064 fps | 95.6% |
| Alliant Reloder-16 | <<locked>> | 92% | 35,128 psi | 56% | 2139 fps | 95% |
| Alliant Reloder-17 | <<locked>> | 84% | 30,618 psi | 49% | 2067 fps | 95.1% |
| Baschieri & Pellagri 106 | <<locked>> | 80% | 48,283 psi | 77% | 2178 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 36,463 psi | 58% | 2119 fps | 95.9% |
| Bofors RP3 | <<locked>> | 80% | 30,255 psi | 48% | 2014 fps | 96.3% |
| Bofors RP7 | <<locked>> | 98% | 49,211 psi | 78% | 2283 fps | 95.2% |
| Hodgdon Benchmark | <<locked>> | 80% | 41,611 psi | 66% | 2129 fps | 99.5% |
| Hodgdon BL-C2 | <<locked>> | 80% | 37,507 psi | 59% | 2146 fps | 99% |
| Hodgdon CFE223 | 44.5 gr | 80% | 41,060 psi | 65% | 2254 fps | 97.8% |
| Hodgdon H322 | <<locked>> | 80% | 45,078 psi | 71% | 2218 fps | 100% |
| Hodgdon H335 | <<locked>> | 80% | 45,571 psi | 72% | 2238 fps | 100% |
| Hodgdon H380 | <<locked>> | 86% | 38,305 psi | 61% | 2149 fps | 95.7% |
| Hodgdon H414 | <<locked>> | 98% | 44,962 psi | 71% | 2306 fps | 95% |
| Hodgdon H4895 | <<locked>> | 80% | 37,739 psi | 60% | 2129 fps | 98% |
| Hodgdon Hybrid 100V | <<locked>> | 90% | 30,226 psi | 48% | 2011 fps | 95.1% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 33,837 psi | 54% | 2103 fps | 97.4% |
| Hodgdon TrailBoss | <<locked>> | 80% | 25,846 psi | 41% | 1234 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 36,448 psi | 58% | 2093 fps | 97.6% |
| IMR 3031 | <<locked>> | 80% | 36,825 psi | 58% | 2136 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 33,489 psi | 53% | 2024 fps | 95.6% |
| IMR 4166 Enduron | <<locked>> | 88% | 46,499 psi | 74% | 2215 fps | 95.2% |
| IMR 4198 | <<locked>> | 80% | 47,108 psi | 75% | 2156 fps | 100% |
| IMR 4451 Enduron | <<locked>> | 96% | 48,298 psi | 77% | 2274 fps | 95.5% |
| IMR 4831 | <<locked>> | 94% | 35,143 psi | 56% | 2136 fps | 95.4% |
| IMR 4895 | <<locked>> | 80% | 34,200 psi | 54% | 2087 fps | 96.6% |
| IMR 8208 XBR | <<locked>> | 80% | 39,450 psi | 63% | 2129 fps | 98.8% |
| Lovex D073.5 | <<locked>> | 80% | 44,063 psi | 70% | 2201 fps | 99.8% |
| Lovex D073.6 | <<locked>> | 80% | 35,810 psi | 57% | 2106 fps | 99.4% |
| Lovex S060 | <<locked>> | 80% | 38,377 psi | 61% | 2073 fps | 97.6% |
| Lovex S062 | <<locked>> | 80% | 33,185 psi | 53% | 2031 fps | 97.6% |
| Lovex S065 | <<locked>> | 94% | 41,800 psi | 66% | 2185 fps | 95.6% |
| Lovex S070 | <<locked>> | 98% | 44,454 psi | 70% | 2247 fps | 95% |
| Norma 200 | <<locked>> | 80% | 52,460 psi | 83% | 2241 fps | 100% |
| Norma 201 | <<locked>> | 80% | 37,028 psi | 59% | 2090 fps | 98.5% |
| Norma 202 | <<locked>> | 80% | 36,912 psi | 59% | 2100 fps | 99.8% |
| Norma 203B | <<locked>> | 80% | 32,851 psi | 52% | 2054 fps | 96.1% |
| Norma URP | <<locked>> | 94% | 37,028 psi | 59% | 2175 fps | 95.7% |
| Ramshot Big Game | <<locked>> | 80% | 32,343 psi | 51% | 2060 fps | 95.4% |
| Ramshot TAC | <<locked>> | 80% | 39,276 psi | 62% | 2129 fps | 95.1% |
| Ramshot Wild Boar | <<locked>> | 80% | 38,319 psi | 61% | 2146 fps | 97.6% |
| Ramshot X-Terminator | <<locked>> | 80% | 42,815 psi | 68% | 2172 fps | 98.3% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 25,904 psi | 41% | 1263 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 44,280 psi | 70% | 2201 fps | 99.9% |
| ReloadSwiss RS 50 | <<locked>> | 90% | 44,266 psi | 70% | 2224 fps | 95.4% |
| ReloadSwiss RS 52 | 42.2 gr | 80% | 34,519 psi | 55% | 2139 fps | 96% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 28,601 psi | 45% | 2024 fps | 96.9% |
| ReloadSwiss RS 62 | <<locked>> | 94% | 36,230 psi | 57% | 2188 fps | 95.2% |
| ReloadSwiss RS 70 | <<locked>> | 96% | 39,842 psi | 63% | 2244 fps | 95.1% |
| Rottweil R 901 | <<locked>> | 80% | 40,654 psi | 64% | 2126 fps | 99.9% |
| Rottweil R 902 | <<locked>> | 80% | 35,201 psi | 56% | 2047 fps | 98% |
| Rottweil R 903 | <<locked>> | 80% | 28,471 psi | 45% | 1965 fps | 95.2% |
| Rottweil R 907 | <<locked>> | 98% | 49,211 psi | 78% | 2283 fps | 95.2% |
| Shooters World Long Rifle | <<locked>> | 94% | 41,800 psi | 66% | 2185 fps | 95.6% |
| Shooters World Match Rifle | <<locked>> | 80% | 35,810 psi | 57% | 2106 fps | 99.4% |
| Shooters World Precision | <<locked>> | 80% | 33,185 psi | 53% | 2031 fps | 97.6% |
| Shooters World SW4350 | <<locked>> | 98% | 44,454 psi | 70% | 2247 fps | 95% |
| Shooters World Tactical Rifle | <<locked>> | 80% | 46,847 psi | 74% | 2215 fps | 99.6% |
| SNPE Vectan BA6 1/2 | <<locked>> | 80% | 53,461 psi | 85% | 2001 fps | 100% |
| SNPE Vectan SP 10 | <<locked>> | 80% | 49,429 psi | 78% | 2280 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 82% | 31,647 psi | 50% | 2051 fps | 95.2% |
| SNPE Vectan SP 3 | <<locked>> | 80% | 47,094 psi | 75% | 2205 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 37,275 psi | 59% | 2103 fps | 95.2% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 36,143 psi | 57% | 2096 fps | 97% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 38,537 psi | 61% | 2057 fps | 99.8% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 31,604 psi | 50% | 1949 fps | 99.6% |
| SNPE Vectan Tubal 7000 | <<locked>> | 98% | 46,688 psi | 74% | 2224 fps | 95.3% |
| Somchem S321 | <<locked>> | 80% | 42,380 psi | 67% | 2201 fps | 99.5% |
| Somchem S335 | <<locked>> | 80% | 38,145 psi | 60% | 2064 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 37,086 psi | 59% | 2110 fps | 97.2% |
| Somchem S355 | <<locked>> | 80% | 29,733 psi | 47% | 1978 fps | 95.4% |
| Somchem S365 | <<locked>> | 88% | 27,427 psi | 43% | 1998 fps | 95.5% |
| Vihtavuori N130 | <<locked>> | 80% | 43,729 psi | 69% | 2113 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 38,653 psi | 61% | 2057 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 33,924 psi | 54% | 2041 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 34,824 psi | 55% | 2047 fps | 99.7% |
| Vihtavuori N150 | <<locked>> | 80% | 28,079 psi | 45% | 1929 fps | 96.3% |
| Vihtavuori N160 | <<locked>> | 92% | 36,593 psi | 58% | 2136 fps | 95.4% |
| Vihtavuori N530 | <<locked>> | 80% | 39,479 psi | 63% | 2129 fps | 98.9% |
| Vihtavuori N540 | <<locked>> | 80% | 33,359 psi | 53% | 2034 fps | 99.2% |
| Vihtavuori N550 | <<locked>> | 92% | 35,592 psi | 56% | 2136 fps | 95% |
| Winchester 6.5 StaBALL | <<locked>> | 86% | 30,777 psi | 49% | 1991 fps | 95.3% |
| Winchester 748 | <<locked>> | 80% | 38,363 psi | 61% | 2165 fps | 99.3% |
| Winchester 760 | <<locked>> | 98% | 45,208 psi | 72% | 2310 fps | 95.1% |
| Winchester StaBALL Match | <<locked>> | 80% | 35,230 psi | 56% | 2100 fps | 97.4% |
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 105 powders for .338-06 A-Square loaded with the .338 | 250gr | Sierra GameKing. ReloadSwiss RS 60 delivers the highest muzzle velocity at 2,497 fps; across all powders the maximum-charge window runs from 1,381 fps to 2,497 fps. Accurate 4350 gives the best case fill at 100 %, and 105 of the 105 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (435 MPa), the top charges use 55–90 %, leaving at least 10 % headroom. The 250.0 gr projectile in 0.338" calls for a 1:14.0 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 .338-06 A-Square with the .338 | 250gr | Sierra GameKing 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.