Load Specifications
Load data in caliber .458 Lott with .458 | 500gr | Hornady InterBond RN bullet and 94 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Hodgdon CFE223, 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.
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Max Load - Barrel Length: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 1680 | <<locked>> | 82% | 55,883 psi | 90% | 2044 fps | 100% |
| Accurate 2015 | <<locked>> | 94% | 55,622 psi | 89% | 2103 fps | 100% |
| Accurate 2200 | <<locked>> | 84% | 53,243 psi | 85% | 2139 fps | 98.8% |
| Accurate 2230 | <<locked>> | 84% | 53,621 psi | 86% | 2149 fps | 99.1% |
| Accurate 2460 | <<locked>> | 90% | 54,172 psi | 87% | 2129 fps | 100% |
| Accurate 2495ᴾ | <<locked>> | 100% | 54,665 psi | 88% | 2146 fps | 100% |
| Accurate 2520 | <<locked>> | 94% | 54,969 psi | 88% | 2172 fps | 100% |
| Accurate 4064ᴾ | <<locked>> | 100% | 50,691 psi | 81% | 2142 fps | 100% |
| Accurate LT-30 | <<locked>> | 86% | 53,635 psi | 86% | 2031 fps | 100% |
| Accurate LT-32 | <<locked>> | 86% | 54,099 psi | 87% | 2047 fps | 100% |
| ADI AR 2206H | <<locked>> | 96% | 54,302 psi | 87% | 2172 fps | 99.5% |
| ADI AR 2207 | <<locked>> | 84% | 54,752 psi | 88% | 2044 fps | 100% |
| ADI AR 2208ᴾ | <<locked>> | 100% | 51,808 psi | 83% | 2126 fps | 98.7% |
| ADI AR 2219 | <<locked>> | 86% | 53,011 psi | 85% | 2126 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 94% | 53,998 psi | 87% | 2142 fps | 99.9% |
| Alliant AR-Comp | <<locked>> | 96% | 56,043 psi | 90% | 2159 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 90% | 55,288 psi | 89% | 2221 fps | 99.8% |
| Alliant Power Pro 2000-MR | <<locked>> | 98% | 53,795 psi | 86% | 2257 fps | 98.9% |
| Alliant Reloder- TS 15.5ᴾ | <<locked>> | 100% | 50,212 psi | 81% | 2142 fps | 99.6% |
| Alliant Reloder-10x | <<locked>> | 90% | 55,854 psi | 90% | 2110 fps | 100% |
| Alliant Reloder-15ᴾ | <<locked>> | 100% | 54,752 psi | 88% | 2198 fps | 99.2% |
| Alliant Reloder-17ᴾ | <<locked>> | 100% | 44,657 psi | 72% | 2142 fps | 98.6% |
| Alliant Reloder-7 | <<locked>> | 84% | 55,840 psi | 90% | 2060 fps | 100% |
| Baschieri & Pellagri 106 | <<locked>> | 88% | 55,492 psi | 89% | 2070 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 96% | 53,708 psi | 86% | 2185 fps | 98.7% |
| Bofors RP3ᴾ | <<locked>> | 100% | 50,082 psi | 80% | 2152 fps | 99.6% |
| Hodgdon Benchmark | <<locked>> | 92% | 53,534 psi | 86% | 2096 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 96% | 55,506 psi | 89% | 2205 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 92% | 53,853 psi | 86% | 2238 fps | 99.2% |
| Hodgdon H322 | <<locked>> | 90% | 54,824 psi | 88% | 2142 fps | 100% |
| Hodgdon H335 | <<locked>> | 90% | 56,115 psi | 90% | 2172 fps | 100% |
| Hodgdon H380ᴾ | <<locked>> | 100% | 52,402 psi | 84% | 2162 fps | 97.9% |
| Hodgdon H4198 | <<locked>> | 84% | 55,651 psi | 89% | 2064 fps | 100% |
| Hodgdon H4895 | <<locked>> | 96% | 54,665 psi | 88% | 2182 fps | 99.7% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 35,578 psi | 57% | 1939 fps | 96.2% |
| Hodgdon LEVERevolutionᴾ | <<locked>> | 100% | 56,101 psi | 90% | 2244 fps | 99.9% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 34,040 psi | 55% | 1237 fps | 100% |
| Hodgdon VARGET | <<locked>> | 98% | 56,362 psi | 90% | 2185 fps | 99.8% |
| IMR 3031 | <<locked>> | 96% | 53,113 psi | 85% | 2169 fps | 100% |
| IMR 4064ᴾ | <<locked>> | 100% | 54,563 psi | 87% | 2152 fps | 99.2% |
| IMR 4166 Enduron | <<locked>> | 98% | 56,347 psi | 90% | 2139 fps | 96.2% |
| IMR 4198 | <<locked>> | 88% | 53,548 psi | 86% | 2044 fps | 100% |
| IMR 4895ᴾ | <<locked>> | 100% | 56,043 psi | 90% | 2224 fps | 99.6% |
| IMR 8208 XBR | <<locked>> | 94% | 53,998 psi | 87% | 2142 fps | 99.9% |
| Lovex D073.4 | <<locked>> | 84% | 54,317 psi | 87% | 2133 fps | 100% |
| Lovex D073.5 | <<locked>> | 90% | 54,201 psi | 87% | 2136 fps | 100% |
| Lovex D073.6 | <<locked>> | 98% | 56,275 psi | 90% | 2195 fps | 100% |
| Lovex S060 | <<locked>> | 96% | 55,303 psi | 89% | 2119 fps | 99.5% |
| Lovex S062ᴾ | <<locked>> | 100% | 53,592 psi | 86% | 2152 fps | 99.9% |
| Norma 200 | <<locked>> | 86% | 55,956 psi | 90% | 2090 fps | 100% |
| Norma 201 | <<locked>> | 98% | 56,362 psi | 90% | 2169 fps | 100% |
| Norma 202 | <<locked>> | 96% | 53,156 psi | 85% | 2139 fps | 100% |
| Norma 203Bᴾ | <<locked>> | 100% | 53,766 psi | 86% | 2192 fps | 99.4% |
| Ramshot Big Gameᴾ | <<locked>> | 100% | 54,215 psi | 87% | 2211 fps | 99.3% |
| Ramshot TAC | <<locked>> | 94% | 54,708 psi | 88% | 2152 fps | 97.6% |
| Ramshot Wild Boar | <<locked>> | 94% | 53,214 psi | 85% | 2169 fps | 99.3% |
| Ramshot X-Terminator | <<locked>> | 92% | 55,767 psi | 89% | 2149 fps | 99.4% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 34,214 psi | 55% | 1266 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 90% | 54,157 psi | 87% | 2136 fps | 100% |
| ReloadSwiss RS 50ᴾ | <<locked>> | 100% | 53,432 psi | 86% | 2146 fps | 96.4% |
| ReloadSwiss RS 52 | <<locked>> | 98% | 54,157 psi | 87% | 2247 fps | 99.2% |
| ReloadSwiss RS 60ᴾ | <<locked>> | 100% | 47,761 psi | 77% | 2195 fps | 100% |
| Rottweil R 901 | <<locked>> | 94% | 54,375 psi | 87% | 2123 fps | 100% |
| Rottweil R 902 | <<locked>> | 98% | 53,359 psi | 86% | 2129 fps | 99.8% |
| Rottweil R 903ᴾ | <<locked>> | 100% | 46,673 psi | 75% | 2106 fps | 99.1% |
| Shooters World AR Plus | <<locked>> | 84% | 54,317 psi | 87% | 2133 fps | 100% |
| Shooters World Match Rifle | <<locked>> | 98% | 56,275 psi | 90% | 2195 fps | 100% |
| Shooters World Precisionᴾ | <<locked>> | 100% | 53,592 psi | 86% | 2152 fps | 99.9% |
| Shooters World Tactical Rifle | <<locked>> | 88% | 54,447 psi | 87% | 2113 fps | 99.8% |
| SNPE Vectan BA6 1/2 | <<locked>> | 84% | 54,810 psi | 88% | 1841 fps | 100% |
| SNPE Vectan SP 10 | <<locked>> | 86% | 53,432 psi | 86% | 2136 fps | 100% |
| SNPE Vectan SP 11ᴾ | <<locked>> | 100% | 48,834 psi | 78% | 2152 fps | 98.8% |
| SNPE Vectan SP 3 | <<locked>> | 88% | 53,606 psi | 86% | 2090 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 96% | 55,970 psi | 90% | 2172 fps | 98.2% |
| SNPE Vectan SP 9 | <<locked>> | 98% | 56,028 psi | 90% | 2192 fps | 99.5% |
| SNPE Vectan Tubal 3000 | <<locked>> | 96% | 55,999 psi | 90% | 2090 fps | 100% |
| SNPE Vectan Tubal 5000ᴾ | <<locked>> | 100% | 51,459 psi | 83% | 2054 fps | 100% |
| Somchem S321 | <<locked>> | 92% | 55,129 psi | 88% | 2175 fps | 100% |
| Somchem S335 | <<locked>> | 96% | 54,418 psi | 87% | 2090 fps | 100% |
| Somchem S341 | <<locked>> | 96% | 55,085 psi | 88% | 2169 fps | 99.4% |
| Somchem S355ᴾ | <<locked>> | 100% | 47,761 psi | 77% | 2106 fps | 99.1% |
| Somchem S365ᴾ | <<locked>> | 100% | 34,287 psi | 55% | 1975 fps | 97.4% |
| Vihtavuori N120 | <<locked>> | 84% | 54,694 psi | 88% | 2005 fps | 100% |
| Vihtavuori N130 | <<locked>> | 92% | 55,912 psi | 90% | 2070 fps | 100% |
| Vihtavuori N133 | <<locked>> | 96% | 55,550 psi | 89% | 2080 fps | 100% |
| Vihtavuori N135ᴾ | <<locked>> | 100% | 54,911 psi | 88% | 2136 fps | 100% |
| Vihtavuori N140 | <<locked>> | 98% | 53,548 psi | 86% | 2119 fps | 100% |
| Vihtavuori N150ᴾ | <<locked>> | 100% | 46,122 psi | 74% | 2060 fps | 99.6% |
| Vihtavuori N160ᴾ | <<locked>> | 100% | 40,828 psi | 65% | 2018 fps | 95.7% |
| Vihtavuori N530 | <<locked>> | 94% | 54,708 psi | 88% | 2142 fps | 99.9% |
| Vihtavuori N540ᴾ | <<locked>> | 100% | 55,158 psi | 88% | 2159 fps | 100% |
| Winchester 6.5 StaBALLᴾ | <<locked>> | 100% | 42,206 psi | 68% | 2014 fps | 97.9% |
| Winchester 748 | <<locked>> | 94% | 53,040 psi | 85% | 2178 fps | 100% |
| Winchester StaBALL Match | <<locked>> | 98% | 55,564 psi | 89% | 2201 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 1680 | <<locked>> | 80% | 52,417 psi | 84% | 2008 fps | 100% |
| Accurate 2015 | <<locked>> | 80% | 36,289 psi | 58% | 1867 fps | 100% |
| Accurate 2200 | <<locked>> | 80% | 46,833 psi | 75% | 2057 fps | 97.9% |
| Accurate 2230 | <<locked>> | 80% | 46,673 psi | 75% | 2064 fps | 98.2% |
| Accurate 2460 | <<locked>> | 80% | 38,899 psi | 62% | 1939 fps | 99.6% |
| Accurate 2495 | <<locked>> | 80% | 28,631 psi | 46% | 1798 fps | 99.8% |
| Accurate 2520 | <<locked>> | 80% | 34,301 psi | 55% | 1900 fps | 98.7% |
| Accurate 4064 | <<locked>> | 80% | 27,151 psi | 44% | 1781 fps | 97.9% |
| Accurate LT-30 | <<locked>> | 80% | 44,904 psi | 72% | 1932 fps | 100% |
| Accurate LT-32 | <<locked>> | 80% | 45,295 psi | 73% | 1942 fps | 99.9% |
| ADI AR 2206H | <<locked>> | 80% | 33,127 psi | 53% | 1864 fps | 95.3% |
| ADI AR 2207 | <<locked>> | 80% | 48,530 psi | 78% | 1978 fps | 100% |
| ADI AR 2208 | <<locked>> | 88% | 36,245 psi | 58% | 1903 fps | 95.4% |
| ADI AR 2219 | <<locked>> | 80% | 43,352 psi | 70% | 2011 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 80% | 35,070 psi | 56% | 1877 fps | 97.3% |
| Alliant AR-Comp | <<locked>> | 80% | 33,330 psi | 53% | 1883 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 80% | 40,030 psi | 64% | 2014 fps | 98.1% |
| Alliant Power Pro 2000-MR | 72 gr | 88% | 38,740 psi | 62% | 2031 fps | 95.5% |
| Alliant Reloder- TS 15.5 | <<locked>> | 84% | 30,632 psi | 49% | 1844 fps | 95.6% |
| Alliant Reloder-10x | <<locked>> | 80% | 41,394 psi | 66% | 1942 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 86% | 35,360 psi | 57% | 1926 fps | 95.5% |
| Alliant Reloder-17 | <<locked>> | 92% | 34,534 psi | 55% | 1969 fps | 95.7% |
| Alliant Reloder-7 | <<locked>> | 80% | 49,429 psi | 79% | 1991 fps | 100% |
| Baschieri & Pellagri 106 | <<locked>> | 80% | 43,207 psi | 69% | 1932 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 86% | 38,928 psi | 62% | 1982 fps | 95.7% |
| Bofors RP3 | <<locked>> | 84% | 29,617 psi | 47% | 1837 fps | 95.4% |
| Hodgdon Benchmark | <<locked>> | 80% | 37,434 psi | 60% | 1880 fps | 98.3% |
| Hodgdon BL-C2 | <<locked>> | 80% | 32,489 psi | 52% | 1883 fps | 97.3% |
| Hodgdon CFE223 | 67 gr | 80% | 36,042 psi | 58% | 1975 fps | 95.5% |
| Hodgdon H322 | <<locked>> | 80% | 39,856 psi | 64% | 1962 fps | 100% |
| Hodgdon H335 | <<locked>> | 80% | 40,103 psi | 64% | 1975 fps | 99.8% |
| Hodgdon H380 | <<locked>> | 92% | 40,350 psi | 65% | 2001 fps | 95.4% |
| Hodgdon H4198 | <<locked>> | 80% | 49,414 psi | 79% | 1995 fps | 100% |
| Hodgdon H4895 | <<locked>> | 80% | 33,301 psi | 53% | 1873 fps | 96.1% |
| Hodgdon Hybrid 100V | <<locked>> | 98% | 33,504 psi | 54% | 1900 fps | 95.4% |
| Hodgdon LEVERevolution | <<locked>> | 82% | 31,662 psi | 51% | 1880 fps | 95.8% |
| Hodgdon TrailBoss | <<locked>> | 80% | 25,208 psi | 40% | 1099 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 32,271 psi | 52% | 1837 fps | 95.5% |
| IMR 3031 | <<locked>> | 80% | 31,952 psi | 51% | 1880 fps | 99.8% |
| IMR 4064 | <<locked>> | 86% | 35,708 psi | 57% | 1890 fps | 95.6% |
| IMR 4166 Enduron | <<locked>> | 96% | 52,924 psi | 85% | 2100 fps | 95.5% |
| IMR 4198 | <<locked>> | 80% | 42,496 psi | 68% | 1919 fps | 100% |
| IMR 4895 | <<locked>> | 82% | 31,937 psi | 51% | 1873 fps | 95% |
| IMR 8208 XBR | <<locked>> | 80% | 35,070 psi | 56% | 1877 fps | 97.3% |
| Lovex D073.4 | <<locked>> | 80% | 47,311 psi | 76% | 2054 fps | 99.9% |
| Lovex D073.5 | <<locked>> | 80% | 38,595 psi | 62% | 1939 fps | 98.9% |
| Lovex D073.6 | <<locked>> | 80% | 30,879 psi | 50% | 1847 fps | 97.9% |
| Lovex S060 | <<locked>> | 80% | 34,577 psi | 55% | 1827 fps | 95.7% |
| Lovex S062 | <<locked>> | 80% | 29,240 psi | 47% | 1785 fps | 95.5% |
| Norma 200 | <<locked>> | 80% | 46,644 psi | 75% | 1988 fps | 100% |
| Norma 201 | <<locked>> | 80% | 32,576 psi | 52% | 1834 fps | 96.7% |
| Norma 202 | <<locked>> | 80% | 32,343 psi | 52% | 1847 fps | 98.8% |
| Norma 203B | <<locked>> | 84% | 32,590 psi | 52% | 1880 fps | 95.2% |
| Ramshot Big Game | <<locked>> | 86% | 34,577 psi | 55% | 1926 fps | 95.3% |
| Ramshot TAC | <<locked>> | 86% | 42,366 psi | 68% | 1991 fps | 95% |
| Ramshot Wild Boar | <<locked>> | 80% | 33,634 psi | 54% | 1883 fps | 95.4% |
| Ramshot X-Terminator | <<locked>> | 80% | 38,159 psi | 61% | 1913 fps | 96.6% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 25,338 psi | 41% | 1129 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 39,349 psi | 63% | 1942 fps | 99.3% |
| ReloadSwiss RS 50 | <<locked>> | 96% | 46,963 psi | 75% | 2067 fps | 95.1% |
| ReloadSwiss RS 52 | 68.2 gr | 86% | 36,506 psi | 59% | 1995 fps | 95.8% |
| ReloadSwiss RS 60 | <<locked>> | 84% | 28,776 psi | 46% | 1850 fps | 95.9% |
| Rottweil R 901 | <<locked>> | 80% | 36,187 psi | 58% | 1877 fps | 99.2% |
| Rottweil R 902 | <<locked>> | 80% | 30,980 psi | 50% | 1798 fps | 96.1% |
| Rottweil R 903 | <<locked>> | 86% | 29,660 psi | 48% | 1834 fps | 95% |
| Shooters World AR Plus | <<locked>> | 80% | 47,311 psi | 76% | 2054 fps | 99.9% |
| Shooters World Match Rifle | <<locked>> | 80% | 30,879 psi | 50% | 1847 fps | 97.9% |
| Shooters World Precision | <<locked>> | 80% | 29,240 psi | 47% | 1785 fps | 95.5% |
| Shooters World Tactical Rifle | <<locked>> | 80% | 41,568 psi | 67% | 1952 fps | 98.4% |
| SNPE Vectan BA6 1/2 | <<locked>> | 80% | 49,487 psi | 79% | 1788 fps | 100% |
| SNPE Vectan SP 10 | <<locked>> | 80% | 43,787 psi | 70% | 2018 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 88% | 33,620 psi | 54% | 1913 fps | 95.1% |
| SNPE Vectan SP 3 | <<locked>> | 80% | 41,989 psi | 67% | 1952 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 86% | 40,001 psi | 64% | 1965 fps | 95.1% |
| SNPE Vectan SP 9 | <<locked>> | 82% | 33,808 psi | 54% | 1880 fps | 95.4% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 34,505 psi | 55% | 1814 fps | 99% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 27,949 psi | 45% | 1716 fps | 98.4% |
| Somchem S321 | <<locked>> | 80% | 37,086 psi | 59% | 1936 fps | 98.1% |
| Somchem S335 | <<locked>> | 80% | 33,852 psi | 54% | 1821 fps | 99.5% |
| Somchem S341 | <<locked>> | 82% | 34,679 psi | 56% | 1890 fps | 95.6% |
| Somchem S355 | <<locked>> | 86% | 31,111 psi | 50% | 1844 fps | 95.2% |
| Somchem S365 | <<locked>> | 96% | 30,327 psi | 49% | 1893 fps | 95.9% |
| Vihtavuori N120 | <<locked>> | 80% | 48,530 psi | 78% | 1942 fps | 100% |
| Vihtavuori N130 | <<locked>> | 80% | 39,204 psi | 63% | 1877 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 34,403 psi | 55% | 1821 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 29,472 psi | 47% | 1798 fps | 99.8% |
| Vihtavuori N140 | <<locked>> | 80% | 30,603 psi | 49% | 1801 fps | 98.6% |
| Vihtavuori N150 | <<locked>> | 84% | 27,789 psi | 45% | 1762 fps | 95.4% |
| Vihtavuori N160 | <<locked>> | 98% | 38,421 psi | 62% | 1978 fps | 95% |
| Vihtavuori N530 | <<locked>> | 80% | 34,824 psi | 56% | 1873 fps | 97.3% |
| Vihtavuori N540 | <<locked>> | 80% | 29,298 psi | 47% | 1791 fps | 97.8% |
| Winchester 6.5 StaBALL | <<locked>> | 94% | 34,925 psi | 56% | 1893 fps | 95.8% |
| Winchester 748 | <<locked>> | 80% | 33,446 psi | 54% | 1900 fps | 97.8% |
| Winchester StaBALL Match | <<locked>> | 80% | 30,821 psi | 49% | 1841 fps | 95.1% |
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 94 powders for .458 Lott loaded with the .458 | 500gr | Hornady InterBond RN. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 2,257 fps; across all powders the maximum-charge window runs from 1,237 fps to 2,257 fps. Accurate 2495 gives the best case fill at 100 %, and 94 of the 94 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (430 MPa), the top charges use 55–90 %, leaving at least 10 % headroom. The 500.0 gr projectile in 0.458" calls for a 1:6.0 twist; slower twists will usually not stabilise this weight. Accurate 2495, Accurate 4064, 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. Hodgdon CFE223, Alliant Power Pro 2000-MR, ReloadSwiss RS 52 rank at the top here: for .458 Lott with the .458 | 500gr | Hornady InterBond RN they combine a high case fill with complete burn and sit in the upper velocity band. 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.