Load Specifications
Load data in caliber .450 Rigby with .457 | 475gr | Rhino Solid 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 Power Pro 2000-MR, ReloadSwiss RS 60 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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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% | 49,879 psi | 86% | 2182 fps | 100% |
| Accurate 2460 | <<locked>> | 84% | 51,242 psi | 88% | 2241 fps | 100% |
| Accurate 2495 | <<locked>> | 92% | 50,053 psi | 86% | 2234 fps | 100% |
| Accurate 2520 | <<locked>> | 86% | 49,110 psi | 85% | 2251 fps | 100% |
| Accurate 4064 | <<locked>> | 94% | 49,850 psi | 86% | 2270 fps | 100% |
| Accurate 4350ᴾ | <<locked>> | 100% | 45,005 psi | 78% | 2277 fps | 98.2% |
| ADI AR 2206H | <<locked>> | 90% | 51,880 psi | 89% | 2297 fps | 99.7% |
| ADI AR 2208 | <<locked>> | 94% | 49,559 psi | 85% | 2254 fps | 99.1% |
| ADI Benchmark 8208 | <<locked>> | 88% | 51,242 psi | 88% | 2260 fps | 100% |
| Alliant AR-Comp | <<locked>> | 88% | 50,908 psi | 88% | 2244 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 82% | 49,487 psi | 85% | 2300 fps | 99.8% |
| Alliant Power Pro 2000-MR | <<locked>> | 92% | 50,836 psi | 88% | 2385 fps | 99.3% |
| Alliant Reloder- TS 15.5 | <<locked>> | 96% | 51,808 psi | 89% | 2310 fps | 99.9% |
| Alliant Reloder-10x | <<locked>> | 82% | 49,995 psi | 86% | 2188 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 92% | 49,472 psi | 85% | 2287 fps | 99.3% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 45,150 psi | 78% | 2280 fps | 98.3% |
| Alliant Reloder-17ᴾ | <<locked>> | 100% | 51,938 psi | 90% | 2405 fps | 99.9% |
| Baschieri & Pellagri 106 | <<locked>> | 82% | 51,909 psi | 89% | 2175 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 90% | 51,140 psi | 88% | 2310 fps | 99.1% |
| Bofors RP3 | <<locked>> | 96% | 51,909 psi | 89% | 2323 fps | 100% |
| Hodgdon Benchmark | <<locked>> | 86% | 50,473 psi | 87% | 2211 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 88% | 49,719 psi | 86% | 2287 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 86% | 51,271 psi | 88% | 2362 fps | 99.5% |
| Hodgdon H322 | <<locked>> | 84% | 51,851 psi | 89% | 2257 fps | 100% |
| Hodgdon H335 | <<locked>> | 82% | 49,458 psi | 85% | 2241 fps | 100% |
| Hodgdon H380 | <<locked>> | 94% | 50,198 psi | 87% | 2290 fps | 98.5% |
| Hodgdon H414ᴾ | <<locked>> | 100% | 48,733 psi | 84% | 2320 fps | 96.2% |
| Hodgdon H4895 | <<locked>> | 90% | 52,330 psi | 90% | 2306 fps | 99.9% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 41,336 psi | 71% | 2185 fps | 98.8% |
| Hodgdon LEVERevolution | <<locked>> | 92% | 50,517 psi | 87% | 2329 fps | 99.9% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 34,809 psi | 60% | 1355 fps | 100% |
| Hodgdon VARGET | <<locked>> | 90% | 50,415 psi | 87% | 2267 fps | 99.8% |
| IMR 3031 | <<locked>> | 90% | 51,532 psi | 89% | 2293 fps | 100% |
| IMR 4064 | <<locked>> | 94% | 52,170 psi | 90% | 2280 fps | 99.5% |
| IMR 4166 Enduron | <<locked>> | 90% | 49,879 psi | 86% | 2221 fps | 96.2% |
| IMR 4198 | <<locked>> | 82% | 50,517 psi | 87% | 2152 fps | 100% |
| IMR 4451 Enduron | <<locked>> | 98% | 51,880 psi | 89% | 2277 fps | 96.5% |
| IMR 4831ᴾ | <<locked>> | 100% | 43,163 psi | 74% | 2231 fps | 97.9% |
| IMR 4895 | <<locked>> | 92% | 50,662 psi | 87% | 2313 fps | 99.7% |
| IMR 8208 XBR | <<locked>> | 88% | 51,242 psi | 88% | 2260 fps | 100% |
| Lovex D073.5 | <<locked>> | 84% | 51,140 psi | 88% | 2251 fps | 100% |
| Lovex D073.6 | <<locked>> | 90% | 50,604 psi | 87% | 2280 fps | 100% |
| Lovex S060 | <<locked>> | 90% | 52,286 psi | 90% | 2241 fps | 99.7% |
| Lovex S062 | <<locked>> | 94% | 51,634 psi | 89% | 2277 fps | 100% |
| Lovex S065ᴾ | <<locked>> | 100% | 50,604 psi | 87% | 2270 fps | 97.7% |
| Lovex S070ᴾ | <<locked>> | 100% | 47,935 psi | 83% | 2254 fps | 96.1% |
| Norma 201 | <<locked>> | 90% | 50,763 psi | 88% | 2254 fps | 100% |
| Norma 202 | <<locked>> | 90% | 50,981 psi | 88% | 2257 fps | 100% |
| Norma 203B | <<locked>> | 94% | 51,837 psi | 89% | 2320 fps | 99.7% |
| Norma URPᴾ | <<locked>> | 100% | 45,266 psi | 78% | 2270 fps | 98.1% |
| Ramshot Big Game | <<locked>> | 94% | 51,924 psi | 90% | 2343 fps | 99.7% |
| Ramshot Hunterᴾ | <<locked>> | 100% | 44,614 psi | 77% | 2264 fps | 96% |
| Ramshot TAC | <<locked>> | 88% | 51,532 psi | 89% | 2274 fps | 98.1% |
| Ramshot Wild Boar | <<locked>> | 88% | 50,589 psi | 87% | 2290 fps | 99.6% |
| Ramshot X-Terminator | <<locked>> | 84% | 49,226 psi | 85% | 2221 fps | 99.3% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 35,128 psi | 61% | 1388 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 84% | 50,894 psi | 88% | 2247 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 94% | 50,894 psi | 88% | 2274 fps | 97.1% |
| ReloadSwiss RS 52 | <<locked>> | 92% | 52,315 psi | 90% | 2382 fps | 99.6% |
| ReloadSwiss RS 60 | <<locked>> | 98% | 52,011 psi | 90% | 2411 fps | 100% |
| ReloadSwiss RS 62ᴾ | <<locked>> | 100% | 44,744 psi | 77% | 2293 fps | 97.8% |
| ReloadSwiss RS 70ᴾ | <<locked>> | 100% | 46,064 psi | 79% | 2310 fps | 97.3% |
| Rottweil R 901 | <<locked>> | 88% | 52,098 psi | 90% | 2241 fps | 100% |
| Rottweil R 902 | <<locked>> | 92% | 51,097 psi | 88% | 2251 fps | 100% |
| Rottweil R 903 | <<locked>> | 98% | 51,619 psi | 89% | 2313 fps | 99.9% |
| Shooters World Long Rifleᴾ | <<locked>> | 100% | 50,604 psi | 87% | 2270 fps | 97.7% |
| Shooters World Match Rifle | <<locked>> | 90% | 50,604 psi | 87% | 2280 fps | 100% |
| Shooters World Precision | <<locked>> | 94% | 51,634 psi | 89% | 2277 fps | 100% |
| Shooters World SW4350ᴾ | <<locked>> | 100% | 47,935 psi | 83% | 2254 fps | 96.1% |
| Shooters World Tactical Rifle | <<locked>> | 82% | 50,662 psi | 87% | 2221 fps | 99.9% |
| SNPE Vectan SP 11 | <<locked>> | 96% | 50,198 psi | 87% | 2326 fps | 99.6% |
| SNPE Vectan SP 3 | <<locked>> | 82% | 50,676 psi | 87% | 2201 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 88% | 49,516 psi | 85% | 2251 fps | 98.2% |
| SNPE Vectan SP 9 | <<locked>> | 90% | 50,198 psi | 87% | 2274 fps | 99.5% |
| SNPE Vectan Tubal 3000 | <<locked>> | 88% | 49,850 psi | 86% | 2172 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 96% | 52,272 psi | 90% | 2205 fps | 100% |
| SNPE Vectan Tubal 7000ᴾ | <<locked>> | 100% | 50,836 psi | 88% | 2231 fps | 96.4% |
| Somchem S321 | <<locked>> | 86% | 52,243 psi | 90% | 2293 fps | 100% |
| Somchem S335 | <<locked>> | 90% | 51,967 psi | 90% | 2208 fps | 100% |
| Somchem S341 | <<locked>> | 90% | 52,315 psi | 90% | 2290 fps | 99.7% |
| Somchem S355 | <<locked>> | 98% | 52,344 psi | 90% | 2313 fps | 99.9% |
| Somchem S365ᴾ | <<locked>> | 100% | 40,277 psi | 69% | 2231 fps | 99.6% |
| Vihtavuori N130 | <<locked>> | 84% | 49,908 psi | 86% | 2146 fps | 100% |
| Vihtavuori N133 | <<locked>> | 88% | 49,850 psi | 86% | 2162 fps | 100% |
| Vihtavuori N135 | <<locked>> | 92% | 50,125 psi | 86% | 2224 fps | 100% |
| Vihtavuori N140 | <<locked>> | 92% | 51,372 psi | 89% | 2241 fps | 100% |
| Vihtavuori N150 | <<locked>> | 98% | 50,473 psi | 87% | 2257 fps | 100% |
| Vihtavuori N160ᴾ | <<locked>> | 100% | 47,761 psi | 82% | 2270 fps | 98.3% |
| Vihtavuori N530 | <<locked>> | 88% | 51,605 psi | 89% | 2260 fps | 100% |
| Vihtavuori N540 | <<locked>> | 92% | 49,545 psi | 85% | 2241 fps | 100% |
| Vihtavuori N550ᴾ | <<locked>> | 100% | 46,601 psi | 80% | 2277 fps | 98.1% |
| Winchester 6.5 StaBALLᴾ | <<locked>> | 100% | 48,689 psi | 84% | 2260 fps | 99.7% |
| Winchester 748 | <<locked>> | 88% | 50,749 psi | 87% | 2300 fps | 100% |
| Winchester 760ᴾ | <<locked>> | 100% | 48,892 psi | 84% | 2323 fps | 96.2% |
| Winchester StaBALL Match | <<locked>> | 90% | 49,559 psi | 85% | 2280 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% | 41,510 psi | 72% | 2073 fps | 100% |
| Accurate 2460 | <<locked>> | 80% | 44,904 psi | 77% | 2159 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 33,968 psi | 59% | 2008 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 40,089 psi | 69% | 2123 fps | 99.9% |
| Accurate 4064 | <<locked>> | 80% | 32,155 psi | 55% | 1998 fps | 99.5% |
| Accurate 4350 | <<locked>> | 92% | 34,098 psi | 59% | 2093 fps | 95.3% |
| ADI AR 2206H | <<locked>> | 80% | 38,043 psi | 66% | 2087 fps | 97.7% |
| ADI AR 2208 | <<locked>> | 80% | 32,460 psi | 56% | 1965 fps | 95.1% |
| ADI Benchmark 8208 | <<locked>> | 80% | 40,045 psi | 69% | 2096 fps | 99.1% |
| Alliant AR-Comp | <<locked>> | 80% | 39,059 psi | 67% | 2093 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 80% | 46,267 psi | 80% | 2254 fps | 99.6% |
| Alliant Power Pro 2000-MR | 79.1 gr | 80% | 34,258 psi | 59% | 2093 fps | 95.2% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 31,415 psi | 54% | 1982 fps | 96.8% |
| Alliant Reloder-10x | <<locked>> | 80% | 46,963 psi | 81% | 2149 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 33,982 psi | 59% | 2031 fps | 96% |
| Alliant Reloder-16 | <<locked>> | 92% | 35,621 psi | 61% | 2106 fps | 95.5% |
| Alliant Reloder-17 | <<locked>> | 84% | 30,922 psi | 53% | 2034 fps | 95.6% |
| Baschieri & Pellagri 106 | <<locked>> | 80% | 48,747 psi | 84% | 2139 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 36,869 psi | 64% | 2087 fps | 96.2% |
| Bofors RP3 | <<locked>> | 80% | 30,676 psi | 53% | 1982 fps | 96.7% |
| Hodgdon Benchmark | <<locked>> | 80% | 42,163 psi | 73% | 2093 fps | 99.6% |
| Hodgdon BL-C2 | <<locked>> | 80% | 38,072 psi | 66% | 2113 fps | 99.2% |
| Hodgdon CFE223 | <<locked>> | 80% | 41,655 psi | 72% | 2218 fps | 98.1% |
| Hodgdon H322 | <<locked>> | 80% | 45,571 psi | 79% | 2178 fps | 100% |
| Hodgdon H335 | <<locked>> | 80% | 46,224 psi | 80% | 2198 fps | 100% |
| Hodgdon H380 | <<locked>> | 84% | 36,274 psi | 63% | 2070 fps | 95.3% |
| Hodgdon H414 | <<locked>> | 98% | 45,716 psi | 79% | 2274 fps | 95.5% |
| Hodgdon H4895 | <<locked>> | 80% | 38,276 psi | 66% | 2096 fps | 98.3% |
| Hodgdon Hybrid 100V | <<locked>> | 90% | 30,574 psi | 53% | 1982 fps | 95.6% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 34,185 psi | 59% | 2067 fps | 97.7% |
| Hodgdon TrailBoss | <<locked>> | 80% | 25,817 psi | 45% | 1207 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 36,941 psi | 64% | 2060 fps | 97.9% |
| IMR 3031 | <<locked>> | 80% | 37,246 psi | 64% | 2096 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 33,982 psi | 59% | 1991 fps | 96% |
| IMR 4166 Enduron | <<locked>> | 88% | 46,862 psi | 81% | 2175 fps | 95.5% |
| IMR 4198 | <<locked>> | 80% | 47,790 psi | 82% | 2119 fps | 100% |
| IMR 4451 Enduron | <<locked>> | 94% | 46,151 psi | 80% | 2198 fps | 95.2% |
| IMR 4831 | <<locked>> | 92% | 33,475 psi | 58% | 2060 fps | 95.1% |
| IMR 4895 | <<locked>> | 80% | 34,722 psi | 60% | 2057 fps | 97% |
| IMR 8208 XBR | <<locked>> | 80% | 40,045 psi | 69% | 2096 fps | 99.1% |
| Lovex D073.5 | <<locked>> | 80% | 44,643 psi | 77% | 2165 fps | 99.9% |
| Lovex D073.6 | <<locked>> | 80% | 36,347 psi | 63% | 2070 fps | 99.5% |
| Lovex S060 | <<locked>> | 80% | 38,856 psi | 67% | 2041 fps | 97.9% |
| Lovex S062 | <<locked>> | 80% | 33,736 psi | 58% | 1998 fps | 97.9% |
| Lovex S065 | <<locked>> | 92% | 39,755 psi | 69% | 2110 fps | 95.3% |
| Lovex S070 | <<locked>> | 98% | 44,991 psi | 78% | 2211 fps | 95.4% |
| Norma 201 | <<locked>> | 80% | 37,333 psi | 64% | 2051 fps | 98.7% |
| Norma 202 | <<locked>> | 80% | 37,362 psi | 64% | 2064 fps | 99.9% |
| Norma 203B | <<locked>> | 80% | 33,344 psi | 57% | 2021 fps | 96.5% |
| Norma URP | <<locked>> | 92% | 35,186 psi | 61% | 2100 fps | 95.3% |
| Ramshot Big Game | <<locked>> | 80% | 32,851 psi | 57% | 2031 fps | 95.9% |
| Ramshot Hunter | <<locked>> | 98% | 41,916 psi | 72% | 2218 fps | 95.2% |
| Ramshot TAC | <<locked>> | 80% | 39,827 psi | 69% | 2096 fps | 95.5% |
| Ramshot Wild Boar | <<locked>> | 80% | 38,885 psi | 67% | 2113 fps | 97.9% |
| Ramshot X-Terminator | <<locked>> | 80% | 43,265 psi | 75% | 2136 fps | 98.6% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,063 psi | 45% | 1237 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 44,976 psi | 78% | 2165 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 88% | 42,018 psi | 72% | 2142 fps | 95% |
| ReloadSwiss RS 52 | 76.6 gr | 80% | 34,896 psi | 60% | 2103 fps | 96.3% |
| ReloadSwiss RS 60 | 77.8 gr | 80% | 28,993 psi | 50% | 1995 fps | 97.4% |
| ReloadSwiss RS 62 | <<locked>> | 94% | 36,767 psi | 63% | 2156 fps | 95.6% |
| ReloadSwiss RS 70 | <<locked>> | 96% | 40,466 psi | 70% | 2211 fps | 95.6% |
| Rottweil R 901 | <<locked>> | 80% | 41,133 psi | 71% | 2090 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 35,607 psi | 61% | 2014 fps | 98.3% |
| Rottweil R 903 | <<locked>> | 80% | 28,892 psi | 50% | 1936 fps | 95.6% |
| Shooters World Long Rifle | <<locked>> | 92% | 39,755 psi | 69% | 2110 fps | 95.3% |
| Shooters World Match Rifle | <<locked>> | 80% | 36,347 psi | 63% | 2070 fps | 99.5% |
| Shooters World Precision | <<locked>> | 80% | 33,736 psi | 58% | 1998 fps | 97.9% |
| Shooters World SW4350 | <<locked>> | 98% | 44,991 psi | 78% | 2211 fps | 95.4% |
| Shooters World Tactical Rifle | <<locked>> | 80% | 47,471 psi | 82% | 2178 fps | 99.7% |
| SNPE Vectan SP 11 | <<locked>> | 82% | 32,068 psi | 55% | 2018 fps | 95.7% |
| SNPE Vectan SP 3 | <<locked>> | 80% | 47,790 psi | 82% | 2165 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 37,739 psi | 65% | 2070 fps | 95.5% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 36,506 psi | 63% | 2060 fps | 97.3% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 39,102 psi | 67% | 2021 fps | 99.9% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 32,068 psi | 55% | 1916 fps | 99.7% |
| SNPE Vectan Tubal 7000 | <<locked>> | 96% | 44,512 psi | 77% | 2149 fps | 95% |
| Somchem S321 | <<locked>> | 80% | 42,815 psi | 74% | 2162 fps | 99.6% |
| Somchem S335 | <<locked>> | 80% | 38,508 psi | 66% | 2024 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 37,536 psi | 65% | 2073 fps | 97.5% |
| Somchem S355 | <<locked>> | 80% | 30,066 psi | 52% | 1946 fps | 95.8% |
| Somchem S365 | <<locked>> | 86% | 26,092 psi | 45% | 1923 fps | 95% |
| Vihtavuori N130 | <<locked>> | 80% | 44,309 psi | 76% | 2077 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 39,189 psi | 68% | 2021 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 34,476 psi | 59% | 2008 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 35,273 psi | 61% | 2011 fps | 99.8% |
| Vihtavuori N150 | <<locked>> | 80% | 28,471 psi | 49% | 1896 fps | 96.7% |
| Vihtavuori N160 | <<locked>> | 90% | 34,795 psi | 60% | 2057 fps | 95% |
| Vihtavuori N530 | <<locked>> | 80% | 39,871 psi | 69% | 2093 fps | 99.1% |
| Vihtavuori N540 | <<locked>> | 80% | 33,837 psi | 58% | 2001 fps | 99.4% |
| Vihtavuori N550 | <<locked>> | 92% | 36,071 psi | 62% | 2103 fps | 95.4% |
| Winchester 6.5 StaBALL | <<locked>> | 86% | 31,125 psi | 54% | 1959 fps | 95.7% |
| Winchester 748 | <<locked>> | 80% | 38,812 psi | 67% | 2129 fps | 99.5% |
| Winchester 760 | <<locked>> | 98% | 45,832 psi | 79% | 2277 fps | 95.5% |
| Winchester StaBALL Match | <<locked>> | 80% | 35,578 psi | 61% | 2064 fps | 97.7% |
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 95 powders for .450 Rigby loaded with the .457 | 475gr | Rhino Solid. ReloadSwiss RS 60 delivers the highest muzzle velocity at 2,411 fps; across all powders the maximum-charge window runs from 1,355 fps to 2,411 fps. Accurate 4350 gives the best case fill at 100 %, and 95 of the 95 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (400 MPa), the top charges use 60–90 %, leaving at least 10 % headroom. The 475.0 gr projectile in 0.457" calls for a 1:22.5 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 60, ReloadSwiss RS 52 rank at the top here: for .450 Rigby with the .457 | 475gr | Rhino Solid 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.