Load Specifications
Load data in caliber .458 Win.Mag. with .458 | 500gr | A-Square LionLoad bullet and 99 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>> | 92% | 54,070 psi | 87% | 2100 fps | 100% |
| Accurate 2200 | <<locked>> | 84% | 54,911 psi | 88% | 2175 fps | 99.2% |
| Accurate 2230 | <<locked>> | 84% | 55,579 psi | 89% | 2188 fps | 99.4% |
| Accurate 2460 | <<locked>> | 90% | 56,159 psi | 90% | 2162 fps | 100% |
| Accurate 2495 | <<locked>> | 98% | 53,374 psi | 86% | 2146 fps | 100% |
| Accurate 2520 | <<locked>> | 92% | 53,359 psi | 86% | 2169 fps | 100% |
| Accurate 4064ᴾ | <<locked>> | 100% | 52,953 psi | 85% | 2178 fps | 100% |
| Accurate 4350ᴾ | <<locked>> | 100% | 38,754 psi | 62% | 2054 fps | 96% |
| Accurate LT-30 | <<locked>> | 86% | 55,143 psi | 88% | 2064 fps | 100% |
| Accurate LT-32 | <<locked>> | 86% | 55,593 psi | 89% | 2080 fps | 100% |
| ADI AR 2206H | <<locked>> | 96% | 56,101 psi | 90% | 2208 fps | 99.7% |
| ADI AR 2207 | <<locked>> | 84% | 56,246 psi | 90% | 2070 fps | 100% |
| ADI AR 2208ᴾ | <<locked>> | 100% | 53,635 psi | 86% | 2165 fps | 99.1% |
| ADI AR 2219 | <<locked>> | 86% | 54,824 psi | 88% | 2156 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 94% | 55,883 psi | 90% | 2178 fps | 100% |
| Alliant AR-Comp | <<locked>> | 94% | 54,665 psi | 88% | 2156 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 88% | 53,824 psi | 86% | 2218 fps | 99.8% |
| Alliant Power Pro 2000-MR | <<locked>> | 98% | 55,608 psi | 89% | 2297 fps | 99.3% |
| Alliant Reloder- TS 15.5ᴾ | <<locked>> | 100% | 52,199 psi | 84% | 2182 fps | 99.8% |
| Alliant Reloder-10x | <<locked>> | 88% | 54,273 psi | 87% | 2106 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 98% | 53,272 psi | 85% | 2198 fps | 99.2% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 40,712 psi | 65% | 2064 fps | 96.3% |
| Alliant Reloder-17ᴾ | <<locked>> | 100% | 46,180 psi | 74% | 2182 fps | 99.1% |
| Alliant Reloder-7 | <<locked>> | 82% | 54,114 psi | 87% | 2054 fps | 100% |
| Baschieri & Pellagri 106 | <<locked>> | 86% | 53,722 psi | 86% | 2067 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 96% | 55,883 psi | 90% | 2228 fps | 99.1% |
| Bofors RP3ᴾ | <<locked>> | 100% | 52,243 psi | 84% | 2192 fps | 99.8% |
| Hodgdon Benchmark | <<locked>> | 92% | 54,955 psi | 88% | 2129 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 94% | 53,925 psi | 86% | 2205 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 92% | 56,014 psi | 90% | 2277 fps | 99.5% |
| Hodgdon H322 | <<locked>> | 88% | 53,258 psi | 85% | 2139 fps | 100% |
| Hodgdon H335 | <<locked>> | 88% | 54,259 psi | 87% | 2165 fps | 100% |
| Hodgdon H380ᴾ | <<locked>> | 100% | 54,447 psi | 87% | 2201 fps | 98.4% |
| Hodgdon H4198 | <<locked>> | 82% | 53,824 psi | 86% | 2060 fps | 100% |
| Hodgdon H4895 | <<locked>> | 94% | 53,388 psi | 86% | 2182 fps | 99.7% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 36,796 psi | 59% | 1978 fps | 97% |
| Hodgdon LEVERevolution | <<locked>> | 98% | 54,636 psi | 88% | 2244 fps | 99.9% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 34,200 psi | 55% | 1250 fps | 100% |
| Hodgdon VARGET | <<locked>> | 96% | 54,853 psi | 88% | 2182 fps | 99.8% |
| IMR 3031 | <<locked>> | 96% | 55,361 psi | 89% | 2205 fps | 100% |
| IMR 4064 | <<locked>> | 98% | 53,127 psi | 85% | 2149 fps | 99.2% |
| IMR 4166 Enduron | <<locked>> | 96% | 54,636 psi | 88% | 2136 fps | 96.2% |
| IMR 4198 | <<locked>> | 88% | 55,187 psi | 88% | 2073 fps | 100% |
| IMR 4895 | <<locked>> | 98% | 54,592 psi | 88% | 2224 fps | 99.7% |
| IMR 8208 XBR | <<locked>> | 94% | 55,883 psi | 90% | 2178 fps | 100% |
| Lovex D073.4 | <<locked>> | 84% | 56,333 psi | 90% | 2169 fps | 100% |
| Lovex D073.5 | <<locked>> | 90% | 56,057 psi | 90% | 2172 fps | 100% |
| Lovex D073.6 | <<locked>> | 96% | 54,781 psi | 88% | 2195 fps | 100% |
| Lovex S060 | <<locked>> | 94% | 53,708 psi | 86% | 2116 fps | 99.5% |
| Lovex S062ᴾ | <<locked>> | 100% | 55,637 psi | 89% | 2188 fps | 100% |
| Lovex S065ᴾ | <<locked>> | 100% | 45,281 psi | 73% | 2064 fps | 95.9% |
| Norma 200 | <<locked>> | 84% | 54,288 psi | 87% | 2087 fps | 100% |
| Norma 201 | <<locked>> | 96% | 54,926 psi | 88% | 2169 fps | 100% |
| Norma 202 | <<locked>> | 96% | 55,129 psi | 88% | 2172 fps | 100% |
| Norma 203Bᴾ | <<locked>> | 100% | 55,695 psi | 89% | 2228 fps | 99.7% |
| Norma URPᴾ | <<locked>> | 100% | 40,147 psi | 64% | 2057 fps | 96.1% |
| Ramshot Big Gameᴾ | <<locked>> | 100% | 56,260 psi | 90% | 2251 fps | 99.6% |
| Ramshot TAC | <<locked>> | 92% | 53,113 psi | 85% | 2152 fps | 97.6% |
| Ramshot Wild Boar | <<locked>> | 94% | 55,230 psi | 89% | 2208 fps | 99.6% |
| Ramshot X-Terminator | <<locked>> | 90% | 54,041 psi | 87% | 2146 fps | 99.4% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 34,389 psi | 55% | 1280 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 90% | 55,898 psi | 90% | 2169 fps | 100% |
| ReloadSwiss RS 50ᴾ | <<locked>> | 100% | 55,230 psi | 89% | 2185 fps | 97% |
| ReloadSwiss RS 52 | <<locked>> | 96% | 52,663 psi | 84% | 2247 fps | 99.2% |
| ReloadSwiss RS 60ᴾ | <<locked>> | 100% | 49,385 psi | 79% | 2234 fps | 100% |
| Rottweil R 901 | <<locked>> | 94% | 56,072 psi | 90% | 2152 fps | 100% |
| Rottweil R 902 | <<locked>> | 98% | 55,027 psi | 88% | 2162 fps | 100% |
| Rottweil R 903ᴾ | <<locked>> | 100% | 48,646 psi | 78% | 2142 fps | 99.5% |
| Shooters World AR Plus | <<locked>> | 84% | 56,333 psi | 90% | 2169 fps | 100% |
| Shooters World Long Rifleᴾ | <<locked>> | 100% | 45,281 psi | 73% | 2064 fps | 95.9% |
| Shooters World Match Rifle | <<locked>> | 96% | 54,781 psi | 88% | 2195 fps | 100% |
| Shooters World Precisionᴾ | <<locked>> | 100% | 55,637 psi | 89% | 2188 fps | 100% |
| Shooters World Tactical Rifle | <<locked>> | 88% | 56,130 psi | 90% | 2146 fps | 99.9% |
| SNPE Vectan BA6 1/2 | <<locked>> | 84% | 56,043 psi | 90% | 1864 fps | 100% |
| SNPE Vectan SP 10 | <<locked>> | 86% | 55,187 psi | 88% | 2169 fps | 100% |
| SNPE Vectan SP 11ᴾ | <<locked>> | 100% | 50,662 psi | 81% | 2192 fps | 99.2% |
| SNPE Vectan SP 3 | <<locked>> | 88% | 55,405 psi | 89% | 2119 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 94% | 54,244 psi | 87% | 2172 fps | 98.3% |
| SNPE Vectan SP 9 | <<locked>> | 96% | 54,389 psi | 87% | 2188 fps | 99.5% |
| SNPE Vectan Tubal 3000 | <<locked>> | 94% | 54,433 psi | 87% | 2090 fps | 100% |
| SNPE Vectan Tubal 5000ᴾ | <<locked>> | 100% | 53,287 psi | 85% | 2087 fps | 100% |
| Somchem S321 | <<locked>> | 90% | 53,432 psi | 86% | 2172 fps | 100% |
| Somchem S335 | <<locked>> | 96% | 56,304 psi | 90% | 2126 fps | 100% |
| Somchem S341 | <<locked>> | 94% | 53,417 psi | 86% | 2165 fps | 99.4% |
| Somchem S355ᴾ | <<locked>> | 100% | 49,647 psi | 80% | 2146 fps | 99.4% |
| Somchem S365ᴾ | <<locked>> | 100% | 35,592 psi | 57% | 2014 fps | 98.1% |
| Vihtavuori N120 | <<locked>> | 84% | 56,144 psi | 90% | 2031 fps | 100% |
| Vihtavuori N130 | <<locked>> | 90% | 54,433 psi | 87% | 2067 fps | 100% |
| Vihtavuori N133 | <<locked>> | 94% | 54,114 psi | 87% | 2080 fps | 100% |
| Vihtavuori N135 | <<locked>> | 98% | 53,708 psi | 86% | 2136 fps | 100% |
| Vihtavuori N140 | <<locked>> | 98% | 55,564 psi | 89% | 2156 fps | 100% |
| Vihtavuori N150ᴾ | <<locked>> | 100% | 47,935 psi | 77% | 2096 fps | 99.8% |
| Vihtavuori N160ᴾ | <<locked>> | 100% | 42,293 psi | 68% | 2057 fps | 96.5% |
| Vihtavuori N530 | <<locked>> | 92% | 53,084 psi | 85% | 2139 fps | 99.9% |
| Vihtavuori N540 | <<locked>> | 98% | 53,490 psi | 86% | 2156 fps | 100% |
| Vihtavuori N550ᴾ | <<locked>> | 100% | 41,191 psi | 66% | 2064 fps | 96.1% |
| Winchester 6.5 StaBALLᴾ | <<locked>> | 100% | 43,787 psi | 70% | 2054 fps | 98.5% |
| Winchester 748 | <<locked>> | 94% | 54,911 psi | 88% | 2215 fps | 100% |
| Winchester StaBALL Match | <<locked>> | 96% | 53,882 psi | 86% | 2198 fps | 99.8% |
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% | 37,579 psi | 60% | 1900 fps | 100% |
| Accurate 2200 | <<locked>> | 80% | 48,254 psi | 77% | 2093 fps | 98.3% |
| Accurate 2230 | <<locked>> | 80% | 48,399 psi | 78% | 2103 fps | 98.7% |
| Accurate 2460 | <<locked>> | 80% | 40,335 psi | 65% | 1972 fps | 99.8% |
| Accurate 2495 | <<locked>> | 80% | 29,834 psi | 48% | 1827 fps | 99.9% |
| Accurate 2520 | <<locked>> | 80% | 35,665 psi | 57% | 1936 fps | 99.1% |
| Accurate 4064 | <<locked>> | 80% | 28,268 psi | 45% | 1814 fps | 98.4% |
| Accurate 4350 | <<locked>> | 98% | 36,201 psi | 58% | 2011 fps | 95.3% |
| Accurate LT-30 | <<locked>> | 80% | 46,093 psi | 74% | 1959 fps | 100% |
| Accurate LT-32 | <<locked>> | 80% | 46,485 psi | 75% | 1975 fps | 100% |
| ADI AR 2206H | <<locked>> | 80% | 34,301 psi | 55% | 1896 fps | 96% |
| ADI AR 2207 | <<locked>> | 80% | 50,096 psi | 80% | 2008 fps | 100% |
| ADI AR 2208 | <<locked>> | 86% | 35,302 psi | 57% | 1903 fps | 95.4% |
| ADI AR 2219 | <<locked>> | 80% | 44,976 psi | 72% | 2044 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 80% | 36,245 psi | 58% | 1909 fps | 97.8% |
| Alliant AR-Comp | <<locked>> | 80% | 34,577 psi | 55% | 1916 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 80% | 41,466 psi | 66% | 2054 fps | 98.5% |
| Alliant Power Pro 2000-MR | 72.9 gr | 86% | 37,594 psi | 60% | 2028 fps | 95.5% |
| Alliant Reloder- TS 15.5 | <<locked>> | 82% | 29,776 psi | 48% | 1837 fps | 95.5% |
| Alliant Reloder-10x | <<locked>> | 80% | 42,670 psi | 68% | 1972 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 84% | 34,505 psi | 55% | 1923 fps | 95.5% |
| Alliant Reloder-16 | <<locked>> | 98% | 38,334 psi | 61% | 2024 fps | 95.5% |
| Alliant Reloder-17 | <<locked>> | 90% | 33,649 psi | 54% | 1965 fps | 95.8% |
| Alliant Reloder-7 | <<locked>> | 80% | 50,879 psi | 82% | 2021 fps | 100% |
| Baschieri & Pellagri 106 | <<locked>> | 80% | 44,541 psi | 71% | 1962 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 84% | 37,739 psi | 61% | 1975 fps | 95.7% |
| Bofors RP3 | <<locked>> | 82% | 28,892 psi | 46% | 1834 fps | 95.3% |
| Hodgdon Benchmark | <<locked>> | 80% | 38,638 psi | 62% | 1913 fps | 98.8% |
| Hodgdon BL-C2 | <<locked>> | 80% | 33,852 psi | 54% | 1919 fps | 97.9% |
| Hodgdon CFE223 | 69.4 gr | 80% | 37,376 psi | 60% | 2014 fps | 96.3% |
| Hodgdon H322 | <<locked>> | 80% | 41,278 psi | 66% | 1995 fps | 100% |
| Hodgdon H335 | <<locked>> | 80% | 41,655 psi | 67% | 2011 fps | 99.9% |
| Hodgdon H380 | <<locked>> | 90% | 39,175 psi | 63% | 1998 fps | 95.4% |
| Hodgdon H4198 | <<locked>> | 80% | 50,720 psi | 81% | 2028 fps | 100% |
| Hodgdon H4895 | <<locked>> | 80% | 34,461 psi | 55% | 1906 fps | 96.7% |
| Hodgdon Hybrid 100V | <<locked>> | 96% | 32,793 psi | 53% | 1903 fps | 95.5% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 30,763 psi | 49% | 1877 fps | 95.7% |
| Hodgdon TrailBoss | <<locked>> | 80% | 25,309 psi | 41% | 1112 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 33,373 psi | 54% | 1873 fps | 96.2% |
| IMR 3031 | <<locked>> | 80% | 33,141 psi | 53% | 1913 fps | 99.9% |
| IMR 4064 | <<locked>> | 84% | 34,708 psi | 56% | 1886 fps | 95.5% |
| IMR 4166 Enduron | <<locked>> | 94% | 51,387 psi | 82% | 2096 fps | 95.6% |
| IMR 4198 | <<locked>> | 80% | 43,845 psi | 70% | 1946 fps | 100% |
| IMR 4895 | <<locked>> | 82% | 33,083 psi | 53% | 1906 fps | 95.7% |
| IMR 8208 XBR | <<locked>> | 80% | 36,245 psi | 58% | 1909 fps | 97.8% |
| Lovex D073.4 | <<locked>> | 80% | 49,095 psi | 79% | 2090 fps | 100% |
| Lovex D073.5 | <<locked>> | 80% | 40,103 psi | 64% | 1975 fps | 99.3% |
| Lovex D073.6 | <<locked>> | 80% | 32,213 psi | 52% | 1883 fps | 98.4% |
| Lovex S060 | <<locked>> | 80% | 35,549 psi | 57% | 1860 fps | 96.3% |
| Lovex S062 | <<locked>> | 80% | 30,240 psi | 48% | 1818 fps | 96.2% |
| Lovex S065 | <<locked>> | 98% | 42,540 psi | 68% | 2024 fps | 95.2% |
| Norma 200 | <<locked>> | 80% | 48,066 psi | 77% | 2018 fps | 100% |
| Norma 201 | <<locked>> | 80% | 33,663 psi | 54% | 1867 fps | 97.2% |
| Norma 202 | <<locked>> | 80% | 33,547 psi | 54% | 1880 fps | 99.2% |
| Norma 203B | <<locked>> | 82% | 31,778 psi | 51% | 1873 fps | 95.2% |
| Norma URP | <<locked>> | 98% | 37,710 psi | 60% | 2018 fps | 95.3% |
| Ramshot Big Game | <<locked>> | 84% | 33,547 psi | 54% | 1923 fps | 95.3% |
| Ramshot TAC | <<locked>> | 84% | 41,046 psi | 66% | 1985 fps | 95% |
| Ramshot Wild Boar | <<locked>> | 80% | 34,925 psi | 56% | 1923 fps | 96.1% |
| Ramshot X-Terminator | <<locked>> | 80% | 39,305 psi | 63% | 1946 fps | 97.1% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 25,585 psi | 41% | 1142 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 40,770 psi | 65% | 1978 fps | 99.5% |
| ReloadSwiss RS 50 | <<locked>> | 94% | 45,745 psi | 73% | 2067 fps | 95.1% |
| ReloadSwiss RS 52 | 69 gr | 84% | 35,534 psi | 57% | 1991 fps | 95.8% |
| ReloadSwiss RS 60 | <<locked>> | 82% | 27,891 psi | 45% | 1844 fps | 95.8% |
| Rottweil R 901 | <<locked>> | 80% | 37,260 psi | 60% | 1906 fps | 99.5% |
| Rottweil R 902 | <<locked>> | 80% | 32,039 psi | 51% | 1831 fps | 96.7% |
| Rottweil R 903 | <<locked>> | 84% | 29,037 psi | 47% | 1831 fps | 95% |
| Shooters World AR Plus | <<locked>> | 80% | 49,095 psi | 79% | 2090 fps | 100% |
| Shooters World Long Rifle | <<locked>> | 98% | 42,540 psi | 68% | 2024 fps | 95.2% |
| Shooters World Match Rifle | <<locked>> | 80% | 32,213 psi | 52% | 1883 fps | 98.4% |
| Shooters World Precision | <<locked>> | 80% | 30,240 psi | 48% | 1818 fps | 96.2% |
| Shooters World Tactical Rifle | <<locked>> | 80% | 43,091 psi | 69% | 1988 fps | 98.8% |
| SNPE Vectan BA6 1/2 | <<locked>> | 80% | 50,589 psi | 81% | 1811 fps | 100% |
| SNPE Vectan SP 10 | <<locked>> | 80% | 45,368 psi | 73% | 2054 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 86% | 32,634 psi | 52% | 1909 fps | 95% |
| SNPE Vectan SP 3 | <<locked>> | 80% | 43,381 psi | 70% | 1982 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 84% | 38,740 psi | 62% | 1962 fps | 95% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 32,909 psi | 53% | 1873 fps | 95.4% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 35,607 psi | 57% | 1847 fps | 99.4% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 28,964 psi | 46% | 1749 fps | 98.9% |
| Somchem S321 | <<locked>> | 80% | 38,493 psi | 62% | 1972 fps | 98.6% |
| Somchem S335 | <<locked>> | 80% | 34,896 psi | 56% | 1850 fps | 99.7% |
| Somchem S341 | <<locked>> | 80% | 33,634 psi | 54% | 1883 fps | 95.6% |
| Somchem S355 | <<locked>> | 84% | 30,327 psi | 49% | 1841 fps | 95.2% |
| Somchem S365 | <<locked>> | 92% | 27,992 psi | 45% | 1854 fps | 95% |
| Vihtavuori N120 | <<locked>> | 80% | 50,038 psi | 80% | 1969 fps | 100% |
| Vihtavuori N130 | <<locked>> | 80% | 40,495 psi | 65% | 1906 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 35,578 psi | 57% | 1850 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 30,705 psi | 49% | 1831 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 31,647 psi | 51% | 1834 fps | 99% |
| Vihtavuori N150 | <<locked>> | 82% | 27,079 psi | 43% | 1759 fps | 95.4% |
| Vihtavuori N160 | <<locked>> | 96% | 37,318 psi | 60% | 1978 fps | 95% |
| Vihtavuori N530 | <<locked>> | 80% | 35,998 psi | 58% | 1906 fps | 97.9% |
| Vihtavuori N540 | <<locked>> | 80% | 30,356 psi | 49% | 1824 fps | 98.3% |
| Vihtavuori N550 | <<locked>> | 98% | 38,551 psi | 62% | 2021 fps | 95.3% |
| Winchester 6.5 StaBALL | <<locked>> | 92% | 33,823 psi | 54% | 1890 fps | 95.8% |
| Winchester 748 | <<locked>> | 80% | 34,664 psi | 56% | 1936 fps | 98.3% |
| Winchester StaBALL Match | <<locked>> | 80% | 31,908 psi | 51% | 1873 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 117 powders for .458 Win.Mag. loaded with the .458 | 500gr | A-Square LionLoad. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 2,297 fps; across all powders the maximum-charge window runs from 1,250 fps to 2,297 fps. Accurate 4064 gives the best case fill at 100 %, and 117 of the 117 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (430 MPa), the top charges use 46–90 %, leaving at least 10 % headroom. Accurate 4064, Accurate 4350, ADI AR 2208 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 .458 Win.Mag. with the .458 | 500gr | A-Square LionLoad they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, Alliant Reloder-23, Bofors RP7, Hodgdon H414 burn incompletely and react more sensitively to barrel length and temperature. Hodgdon TrailBoss stay subsonic at start load. Always begin at the start load and work up in small increments while checking case and primer for pressure signs.