Load Specifications
Load data in caliber .375 Hoelderlin with .374 | 350gr | Rhino Solid Shank bullet and 95 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are ReloadSwiss RS 60, Alliant Power Pro 2000-MR and Alliant Reloder-17.
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: 25.6"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2015 | <<locked>> | 84% | 49,559 psi | 90% | 2080 fps | 100% |
| Accurate 2495 | <<locked>> | 88% | 47,108 psi | 85% | 2103 fps | 100% |
| Accurate 2520 | <<locked>> | 84% | 48,936 psi | 89% | 2152 fps | 100% |
| Accurate 2700 | <<locked>> | 88% | 47,355 psi | 86% | 2096 fps | 96.3% |
| Accurate 4064 | <<locked>> | 90% | 47,108 psi | 85% | 2139 fps | 100% |
| Accurate 4350ᴾ | <<locked>> | 100% | 48,530 psi | 88% | 2234 fps | 99.6% |
| ADI AR 2206H | <<locked>> | 86% | 48,646 psi | 88% | 2165 fps | 99.9% |
| ADI AR 2208 | <<locked>> | 92% | 49,530 psi | 90% | 2165 fps | 99.8% |
| ADI Benchmark 8208 | <<locked>> | 84% | 48,051 psi | 87% | 2126 fps | 100% |
| Alliant AR-Comp | <<locked>> | 84% | 47,776 psi | 87% | 2103 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 88% | 47,166 psi | 86% | 2247 fps | 99.7% |
| Alliant Reloder- TS 15.5 | <<locked>> | 92% | 48,805 psi | 89% | 2182 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 90% | 49,501 psi | 90% | 2195 fps | 99.8% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 48,124 psi | 87% | 2244 fps | 99.7% |
| Alliant Reloder-17 | <<locked>> | 96% | 48,675 psi | 88% | 2274 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 33,910 psi | 62% | 2041 fps | 98.4% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 37,173 psi | 67% | 2156 fps | 97.2% |
| Baschieri & Pellagri 107 | <<locked>> | 86% | 47,674 psi | 87% | 2175 fps | 99.5% |
| Bofors RP3 | <<locked>> | 92% | 48,747 psi | 88% | 2192 fps | 100% |
| Bofors RP7 | <<locked>> | 96% | 49,574 psi | 90% | 2162 fps | 97.1% |
| Hodgdon Benchmark | <<locked>> | 82% | 47,108 psi | 85% | 2077 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 86% | 49,574 psi | 90% | 2192 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 82% | 47,601 psi | 86% | 2218 fps | 99.8% |
| Hodgdon H380 | <<locked>> | 90% | 47,021 psi | 85% | 2162 fps | 99% |
| Hodgdon H414 | <<locked>> | 98% | 48,820 psi | 89% | 2238 fps | 97.7% |
| Hodgdon H4350 | <<locked>> | 94% | 47,195 psi | 86% | 2165 fps | 95.9% |
| Hodgdon H4895 | <<locked>> | 86% | 49,037 psi | 89% | 2172 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 44,251 psi | 80% | 2146 fps | 99.9% |
| Hodgdon LEVERevolution | <<locked>> | 88% | 47,239 psi | 86% | 2195 fps | 100% |
| Hodgdon Superformance | <<locked>> | 98% | 49,603 psi | 90% | 2264 fps | 97.2% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,085 psi | 64% | 1296 fps | 100% |
| Hodgdon VARGET | <<locked>> | 86% | 47,137 psi | 86% | 2133 fps | 99.9% |
| IMR 3031 | <<locked>> | 86% | 48,341 psi | 88% | 2156 fps | 100% |
| IMR 4064 | <<locked>> | 90% | 49,008 psi | 89% | 2149 fps | 99.8% |
| IMR 4166 Enduron | <<locked>> | 88% | 49,371 psi | 90% | 2133 fps | 97.5% |
| IMR 4350ᴾ | <<locked>> | 100% | 49,313 psi | 89% | 2185 fps | 97.1% |
| IMR 4451 Enduron | <<locked>> | 94% | 48,602 psi | 88% | 2152 fps | 97.3% |
| IMR 4831ᴾ | <<locked>> | 100% | 46,238 psi | 84% | 2192 fps | 99.4% |
| IMR 4895 | <<locked>> | 88% | 47,703 psi | 87% | 2182 fps | 99.9% |
| IMR 8208 XBR | <<locked>> | 84% | 48,051 psi | 87% | 2126 fps | 100% |
| Lovex D073.6 | <<locked>> | 86% | 47,268 psi | 86% | 2142 fps | 100% |
| Lovex S060 | <<locked>> | 86% | 48,776 psi | 89% | 2106 fps | 99.9% |
| Lovex S062 | <<locked>> | 90% | 48,573 psi | 88% | 2146 fps | 100% |
| Lovex S065 | <<locked>> | 96% | 47,674 psi | 87% | 2149 fps | 98.5% |
| Lovex S070 | <<locked>> | 98% | 47,993 psi | 87% | 2172 fps | 97.6% |
| Norma 201 | <<locked>> | 86% | 47,485 psi | 86% | 2119 fps | 100% |
| Norma 202 | <<locked>> | 86% | 47,790 psi | 87% | 2123 fps | 100% |
| Norma 203B | <<locked>> | 90% | 48,704 psi | 88% | 2188 fps | 99.9% |
| Norma 204ᴾ | <<locked>> | 100% | 49,617 psi | 90% | 2218 fps | 95.7% |
| Norma URPᴾ | <<locked>> | 100% | 48,414 psi | 88% | 2231 fps | 99.5% |
| Ramshot Big Game | <<locked>> | 90% | 48,414 psi | 88% | 2205 fps | 99.9% |
| Ramshot Hunterᴾ | <<locked>> | 100% | 47,456 psi | 86% | 2228 fps | 98.2% |
| Ramshot TAC | <<locked>> | 84% | 47,834 psi | 87% | 2139 fps | 98.6% |
| Ramshot Wild Boar | <<locked>> | 84% | 47,036 psi | 85% | 2152 fps | 99.8% |
| Ramshot X-Terminator | <<locked>> | 82% | 48,733 psi | 88% | 2126 fps | 99.8% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 35,491 psi | 64% | 1329 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 90% | 47,558 psi | 86% | 2146 fps | 97.9% |
| ReloadSwiss RS 52 | <<locked>> | 88% | 49,008 psi | 89% | 2244 fps | 99.8% |
| ReloadSwiss RS 60 | <<locked>> | 94% | 48,573 psi | 88% | 2274 fps | 100% |
| ReloadSwiss RS 62ᴾ | <<locked>> | 100% | 48,037 psi | 87% | 2254 fps | 99.4% |
| ReloadSwiss RS 70ᴾ | <<locked>> | 100% | 49,008 psi | 89% | 2277 fps | 99.2% |
| Rottweil R 901 | <<locked>> | 84% | 48,849 psi | 89% | 2106 fps | 100% |
| Rottweil R 902 | <<locked>> | 88% | 48,066 psi | 87% | 2119 fps | 100% |
| Rottweil R 903 | <<locked>> | 94% | 48,602 psi | 88% | 2182 fps | 100% |
| Rottweil R 907 | <<locked>> | 96% | 49,574 psi | 90% | 2162 fps | 97.1% |
| Shooters World Long Rifle | <<locked>> | 96% | 47,674 psi | 87% | 2149 fps | 98.5% |
| Shooters World Match Rifle | <<locked>> | 86% | 47,268 psi | 86% | 2142 fps | 100% |
| Shooters World Precision | <<locked>> | 90% | 48,573 psi | 88% | 2146 fps | 100% |
| Shooters World SW4350 | <<locked>> | 98% | 47,993 psi | 87% | 2172 fps | 97.6% |
| SNPE Vectan SP 11 | <<locked>> | 92% | 46,978 psi | 85% | 2192 fps | 99.8% |
| SNPE Vectan SP 7 | <<locked>> | 86% | 49,240 psi | 89% | 2162 fps | 99.2% |
| SNPE Vectan SP 9 | <<locked>> | 86% | 47,021 psi | 85% | 2142 fps | 99.8% |
| SNPE Vectan Tubal 3000 | <<locked>> | 86% | 49,327 psi | 90% | 2070 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 92% | 49,110 psi | 89% | 2073 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 96% | 47,398 psi | 86% | 2106 fps | 97.2% |
| Somchem S321 | <<locked>> | 82% | 48,414 psi | 88% | 2152 fps | 100% |
| Somchem S335 | <<locked>> | 86% | 48,588 psi | 88% | 2073 fps | 100% |
| Somchem S341 | <<locked>> | 86% | 48,646 psi | 88% | 2156 fps | 99.9% |
| Somchem S355 | <<locked>> | 94% | 49,429 psi | 90% | 2185 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 43,062 psi | 78% | 2192 fps | 100% |
| Vihtavuori N130 | <<locked>> | 82% | 49,356 psi | 90% | 2044 fps | 100% |
| Vihtavuori N133 | <<locked>> | 86% | 49,458 psi | 90% | 2060 fps | 100% |
| Vihtavuori N135 | <<locked>> | 88% | 47,311 psi | 86% | 2093 fps | 100% |
| Vihtavuori N140 | <<locked>> | 88% | 48,167 psi | 87% | 2106 fps | 100% |
| Vihtavuori N150 | <<locked>> | 94% | 47,471 psi | 86% | 2129 fps | 100% |
| Vihtavuori N160 | <<locked>> | 98% | 47,703 psi | 87% | 2185 fps | 99.3% |
| Vihtavuori N530 | <<locked>> | 84% | 48,095 psi | 87% | 2123 fps | 100% |
| Vihtavuori N540 | <<locked>> | 90% | 49,429 psi | 90% | 2146 fps | 100% |
| Vihtavuori N550 | <<locked>> | 98% | 46,746 psi | 85% | 2192 fps | 99.1% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 36,172 psi | 66% | 2100 fps | 98.3% |
| Winchester 6.5 StaBALL | <<locked>> | 98% | 48,312 psi | 88% | 2172 fps | 100% |
| Winchester 748 | <<locked>> | 84% | 47,224 psi | 86% | 2159 fps | 100% |
| Winchester 760 | <<locked>> | 98% | 48,820 psi | 89% | 2238 fps | 97.7% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 30,226 psi | 55% | 2031 fps | 97.8% |
| Winchester StaBALL Match | <<locked>> | 88% | 49,516 psi | 90% | 2188 fps | 100% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 25.6"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2015 | <<locked>> | 80% | 43,888 psi | 80% | 2011 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 36,506 psi | 66% | 1962 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 42,946 psi | 78% | 2077 fps | 100% |
| Accurate 2700 | <<locked>> | 86% | 44,367 psi | 81% | 2054 fps | 95.6% |
| Accurate 4064 | <<locked>> | 80% | 34,534 psi | 63% | 1959 fps | 100% |
| Accurate 4350 | <<locked>> | 86% | 30,269 psi | 55% | 1942 fps | 95.7% |
| ADI AR 2206H | <<locked>> | 80% | 40,234 psi | 73% | 2044 fps | 99.2% |
| ADI AR 2208 | <<locked>> | 80% | 34,374 psi | 62% | 1929 fps | 97.4% |
| ADI Benchmark 8208 | <<locked>> | 80% | 42,279 psi | 77% | 2047 fps | 99.9% |
| Alliant AR-Comp | <<locked>> | 80% | 41,989 psi | 76% | 2034 fps | 100% |
| Alliant Power Pro 2000-MR | 51.6 gr | 80% | 36,318 psi | 66% | 2067 fps | 97.8% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 33,533 psi | 61% | 1946 fps | 98.7% |
| Alliant Reloder-15 | <<locked>> | 80% | 36,114 psi | 66% | 1995 fps | 98.1% |
| Alliant Reloder-16 | <<locked>> | 84% | 29,762 psi | 54% | 1909 fps | 95% |
| Alliant Reloder-17 | 50.8 gr | 80% | 28,964 psi | 53% | 1923 fps | 96.7% |
| Alliant Reloder-23 | <<locked>> | 92% | 26,890 psi | 49% | 1880 fps | 95.4% |
| Alliant Reloder-26 | <<locked>> | 96% | 32,532 psi | 59% | 2057 fps | 95.3% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 39,102 psi | 71% | 2047 fps | 98.2% |
| Bofors RP3 | <<locked>> | 80% | 33,011 psi | 60% | 1952 fps | 98.7% |
| Bofors RP7 | <<locked>> | 90% | 41,408 psi | 75% | 2044 fps | 95.2% |
| Hodgdon Benchmark | <<locked>> | 80% | 44,324 psi | 80% | 2037 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 40,553 psi | 74% | 2067 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 80% | 44,454 psi | 81% | 2175 fps | 99.5% |
| Hodgdon H380 | <<locked>> | 80% | 33,982 psi | 62% | 1952 fps | 96.2% |
| Hodgdon H414 | <<locked>> | 90% | 37,782 psi | 69% | 2067 fps | 95% |
| Hodgdon H4350 | <<locked>> | 92% | 44,396 psi | 81% | 2126 fps | 95.2% |
| Hodgdon H4895 | <<locked>> | 80% | 40,582 psi | 74% | 2051 fps | 99.5% |
| Hodgdon Hybrid 100V | <<locked>> | 82% | 25,498 psi | 46% | 1795 fps | 95.1% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 36,448 psi | 66% | 2031 fps | 99.3% |
| Hodgdon Superformance | <<locked>> | 94% | 43,149 psi | 78% | 2169 fps | 95.7% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,063 psi | 47% | 1155 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 39,146 psi | 71% | 2018 fps | 99.3% |
| IMR 3031 | <<locked>> | 80% | 39,885 psi | 72% | 2044 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 36,042 psi | 65% | 1955 fps | 98.1% |
| IMR 4166 Enduron | <<locked>> | 82% | 41,017 psi | 74% | 2008 fps | 95.7% |
| IMR 4350 | <<locked>> | 94% | 41,104 psi | 75% | 2064 fps | 95.1% |
| IMR 4451 Enduron | <<locked>> | 88% | 40,596 psi | 74% | 2031 fps | 95.5% |
| IMR 4831 | <<locked>> | 86% | 29,660 psi | 54% | 1909 fps | 95.4% |
| IMR 4895 | <<locked>> | 80% | 36,970 psi | 67% | 2018 fps | 98.8% |
| IMR 8208 XBR | <<locked>> | 80% | 42,279 psi | 77% | 2047 fps | 99.9% |
| Lovex D073.6 | <<locked>> | 80% | 38,870 psi | 71% | 2028 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 40,843 psi | 74% | 1995 fps | 99.2% |
| Lovex S062 | <<locked>> | 80% | 35,795 psi | 65% | 1959 fps | 99.3% |
| Lovex S065 | <<locked>> | 86% | 35,201 psi | 64% | 1952 fps | 95.6% |
| Lovex S070 | <<locked>> | 90% | 37,536 psi | 68% | 2011 fps | 95.1% |
| Norma 201 | <<locked>> | 80% | 39,610 psi | 72% | 2008 fps | 99.7% |
| Norma 202 | <<locked>> | 80% | 39,566 psi | 72% | 2011 fps | 100% |
| Norma 203B | <<locked>> | 80% | 35,505 psi | 64% | 1985 fps | 98.4% |
| Norma 204 | <<locked>> | 98% | 46,615 psi | 85% | 2178 fps | 95% |
| Norma URP | <<locked>> | 86% | 31,227 psi | 57% | 1946 fps | 95.7% |
| Ramshot Big Game | <<locked>> | 80% | 34,896 psi | 63% | 1998 fps | 98.1% |
| Ramshot Hunter | <<locked>> | 92% | 36,927 psi | 67% | 2057 fps | 95.6% |
| Ramshot TAC | <<locked>> | 80% | 42,047 psi | 76% | 2054 fps | 97.6% |
| Ramshot Wild Boar | <<locked>> | 80% | 41,234 psi | 75% | 2070 fps | 99.3% |
| Ramshot X-Terminator | <<locked>> | 80% | 45,687 psi | 83% | 2087 fps | 99.7% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,324 psi | 48% | 1181 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 82% | 36,767 psi | 67% | 1978 fps | 95.2% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 37,376 psi | 68% | 2070 fps | 98.4% |
| ReloadSwiss RS 60 | 50.8 gr | 80% | 30,821 psi | 56% | 1975 fps | 99.4% |
| ReloadSwiss RS 62 | <<locked>> | 86% | 30,443 psi | 55% | 1955 fps | 95.1% |
| ReloadSwiss RS 70 | <<locked>> | 90% | 35,244 psi | 64% | 2047 fps | 95.8% |
| Rottweil R 901 | <<locked>> | 80% | 43,424 psi | 79% | 2034 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 37,710 psi | 68% | 1972 fps | 99.5% |
| Rottweil R 903 | <<locked>> | 80% | 30,995 psi | 56% | 1906 fps | 97.9% |
| Rottweil R 907 | <<locked>> | 90% | 41,408 psi | 75% | 2044 fps | 95.2% |
| Shooters World Long Rifle | <<locked>> | 86% | 35,201 psi | 64% | 1952 fps | 95.6% |
| Shooters World Match Rifle | <<locked>> | 80% | 38,870 psi | 71% | 2028 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 35,795 psi | 65% | 1959 fps | 99.3% |
| Shooters World SW4350 | <<locked>> | 90% | 37,536 psi | 68% | 2011 fps | 95.1% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 32,024 psi | 58% | 1946 fps | 97.4% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 40,277 psi | 73% | 2034 fps | 97.7% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 38,769 psi | 70% | 2021 fps | 99% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 41,191 psi | 75% | 1969 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 33,953 psi | 62% | 1870 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 90% | 38,957 psi | 71% | 1988 fps | 95.3% |
| Somchem S321 | <<locked>> | 80% | 45,353 psi | 82% | 2110 fps | 100% |
| Somchem S335 | <<locked>> | 80% | 40,683 psi | 74% | 1972 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 39,827 psi | 72% | 2031 fps | 99.1% |
| Somchem S355 | <<locked>> | 80% | 32,111 psi | 58% | 1913 fps | 98% |
| Somchem S365 | <<locked>> | 80% | 23,250 psi | 42% | 1785 fps | 95.5% |
| Vihtavuori N130 | <<locked>> | 80% | 46,601 psi | 85% | 2011 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 41,365 psi | 75% | 1962 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 36,811 psi | 67% | 1955 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 37,492 psi | 68% | 1962 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 30,414 psi | 55% | 1867 fps | 98.7% |
| Vihtavuori N160 | <<locked>> | 84% | 30,806 psi | 56% | 1906 fps | 95.4% |
| Vihtavuori N530 | <<locked>> | 80% | 42,366 psi | 77% | 2047 fps | 99.9% |
| Vihtavuori N540 | <<locked>> | 80% | 36,013 psi | 65% | 1959 fps | 100% |
| Vihtavuori N550 | <<locked>> | 86% | 31,923 psi | 58% | 1949 fps | 95.7% |
| Vihtavuori N555 | <<locked>> | 92% | 28,224 psi | 51% | 1936 fps | 95.5% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 27,151 psi | 49% | 1808 fps | 95.9% |
| Winchester 748 | <<locked>> | 80% | 41,394 psi | 75% | 2080 fps | 100% |
| Winchester 760 | <<locked>> | 90% | 37,942 psi | 69% | 2070 fps | 95% |
| Winchester StaBALL HD | <<locked>> | 96% | 26,745 psi | 49% | 1932 fps | 95.5% |
| Winchester StaBALL Match | <<locked>> | 80% | 38,043 psi | 69% | 2024 fps | 99.3% |
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 .375 Hoelderlin loaded with the .374 | 350gr | Rhino Solid Shank. ReloadSwiss RS 70 delivers the highest muzzle velocity at 2,277 fps; across all powders the maximum-charge window runs from 1,296 fps to 2,277 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 (380 MPa), the top charges use 55–90 %, leaving at least 10 % headroom. The 350.0 gr projectile in 0.374" calls for a 1:17.0 twist; slower twists will usually not stabilise this weight. Accurate 4350, Alliant Reloder-16, Alliant Reloder-23 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. ReloadSwiss RS 60, Alliant Power Pro 2000-MR, Alliant Reloder-17 rank at the top here: for .375 Hoelderlin with the .374 | 350gr | Rhino Solid Shank 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.