Load Specifications
Load data in caliber .375 Fl. Mag. N.E. with .375 | 300gr | Woodleigh RN SN bullet and 39 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Alliant Reloder-26, Somchem S365 and ReloadSwiss RS 70.
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: 23.62"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 3100ᴾ | <<locked>> | 100% | 39,827 psi | 84% | 2313 fps | 95.9% |
| Accurate 4064 | <<locked>> | 82% | 41,162 psi | 87% | 2280 fps | 100% |
| Accurate 4350 | <<locked>> | 92% | 42,525 psi | 90% | 2375 fps | 98.3% |
| ADI AR 2208 | <<locked>> | 84% | 42,656 psi | 90% | 2297 fps | 98.7% |
| Alliant Reloder- TS 15.5 | <<locked>> | 84% | 42,453 psi | 90% | 2316 fps | 99.6% |
| Alliant Reloder-16 | <<locked>> | 92% | 42,090 psi | 89% | 2382 fps | 98.5% |
| Alliant Reloder-17 | <<locked>> | 88% | 41,887 psi | 89% | 2405 fps | 99.5% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 38,319 psi | 81% | 2343 fps | 98.9% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 42,467 psi | 90% | 2480 fps | 98% |
| Bofors RP3 | <<locked>> | 84% | 42,119 psi | 89% | 2323 fps | 99.6% |
| Hodgdon H380 | <<locked>> | 82% | 40,408 psi | 86% | 2280 fps | 97.3% |
| Hodgdon Hybrid 100V | <<locked>> | 94% | 41,292 psi | 88% | 2329 fps | 99.3% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,462 psi | 75% | 1486 fps | 100% |
| IMR 4064 | <<locked>> | 82% | 42,293 psi | 90% | 2280 fps | 98.8% |
| IMR 4831 | <<locked>> | 92% | 40,712 psi | 86% | 2326 fps | 98% |
| Lovex S062 | <<locked>> | 82% | 42,134 psi | 89% | 2283 fps | 99.7% |
| Lovex S065 | <<locked>> | 88% | 41,582 psi | 88% | 2280 fps | 96.7% |
| Norma 203B | <<locked>> | 82% | 42,090 psi | 89% | 2316 fps | 99.1% |
| Norma URP | <<locked>> | 92% | 42,380 psi | 90% | 2369 fps | 98.2% |
| Ramshot Big Game | <<locked>> | 82% | 41,626 psi | 88% | 2333 fps | 98.9% |
| Ramshot Hunter | <<locked>> | 92% | 41,408 psi | 88% | 2359 fps | 96.2% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 35,940 psi | 76% | 1522 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 86% | 41,771 psi | 89% | 2408 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 92% | 42,105 psi | 89% | 2392 fps | 98% |
| ReloadSwiss RS 70 | <<locked>> | 92% | 42,163 psi | 89% | 2405 fps | 97.4% |
| Rottweil R 903 | <<locked>> | 86% | 42,380 psi | 90% | 2323 fps | 99.5% |
| Shooters World Long Rifle | <<locked>> | 88% | 41,582 psi | 88% | 2280 fps | 96.7% |
| Shooters World Precision | <<locked>> | 82% | 42,134 psi | 89% | 2283 fps | 99.7% |
| SNPE Vectan SP 11 | <<locked>> | 84% | 40,814 psi | 87% | 2323 fps | 98.9% |
| SNPE Vectan Tubal 5000 | <<locked>> | 84% | 42,235 psi | 90% | 2215 fps | 100% |
| Somchem S355 | <<locked>> | 84% | 40,379 psi | 86% | 2277 fps | 99.1% |
| Somchem S365 | <<locked>> | 94% | 40,408 psi | 86% | 2375 fps | 99.9% |
| Vihtavuori N150 | <<locked>> | 86% | 41,176 psi | 87% | 2264 fps | 99.8% |
| Vihtavuori N160 | <<locked>> | 90% | 41,713 psi | 88% | 2323 fps | 98% |
| Vihtavuori N540 | <<locked>> | 82% | 42,569 psi | 90% | 2280 fps | 100% |
| Vihtavuori N550 | <<locked>> | 90% | 40,988 psi | 87% | 2326 fps | 97.7% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 41,858 psi | 89% | 2408 fps | 98.8% |
| Winchester 6.5 StaBALL | <<locked>> | 90% | 41,539 psi | 88% | 2303 fps | 99.4% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 34,243 psi | 73% | 2343 fps | 98.7% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 23.62"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 3100 | <<locked>> | 98% | 37,101 psi | 79% | 2264 fps | 95.1% |
| Accurate 4064 | <<locked>> | 80% | 38,667 psi | 82% | 2238 fps | 100% |
| Accurate 4350 | <<locked>> | 84% | 32,271 psi | 68% | 2175 fps | 95.4% |
| ADI AR 2208 | <<locked>> | 80% | 37,855 psi | 80% | 2208 fps | 97.7% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 37,449 psi | 79% | 2228 fps | 98.9% |
| Alliant Reloder-16 | <<locked>> | 84% | 32,982 psi | 70% | 2188 fps | 95.6% |
| Alliant Reloder-17 | <<locked>> | 80% | 32,213 psi | 68% | 2201 fps | 97.2% |
| Alliant Reloder-23 | <<locked>> | 90% | 28,384 psi | 60% | 2106 fps | 95.1% |
| Alliant Reloder-26 | 77.8 gr | 94% | 34,650 psi | 74% | 2313 fps | 95.3% |
| Bofors RP3 | <<locked>> | 80% | 36,912 psi | 78% | 2228 fps | 98.9% |
| Hodgdon H380 | <<locked>> | 80% | 37,826 psi | 80% | 2234 fps | 96.6% |
| Hodgdon Hybrid 100V | <<locked>> | 82% | 28,282 psi | 60% | 2054 fps | 95.5% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,397 psi | 56% | 1325 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 39,755 psi | 84% | 2238 fps | 98.3% |
| IMR 4831 | <<locked>> | 84% | 31,430 psi | 67% | 2142 fps | 95.1% |
| Lovex S062 | <<locked>> | 80% | 39,595 psi | 84% | 2238 fps | 99.5% |
| Lovex S065 | <<locked>> | 84% | 36,709 psi | 78% | 2188 fps | 95.3% |
| Norma 203B | <<locked>> | 80% | 39,566 psi | 84% | 2274 fps | 98.7% |
| Norma URP | <<locked>> | 84% | 32,793 psi | 70% | 2178 fps | 95.3% |
| Ramshot Big Game | <<locked>> | 80% | 38,972 psi | 83% | 2283 fps | 98.4% |
| Ramshot Hunter | <<locked>> | 90% | 38,841 psi | 82% | 2310 fps | 95.4% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,745 psi | 57% | 1358 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 34,316 psi | 73% | 2257 fps | 99.6% |
| ReloadSwiss RS 62 | <<locked>> | 86% | 34,301 psi | 73% | 2241 fps | 95.7% |
| ReloadSwiss RS 70 | 72.1 gr | 88% | 36,912 psi | 78% | 2297 fps | 95.7% |
| Rottweil R 903 | <<locked>> | 80% | 34,838 psi | 74% | 2182 fps | 98.2% |
| Shooters World Long Rifle | <<locked>> | 84% | 36,709 psi | 78% | 2188 fps | 95.3% |
| Shooters World Precision | <<locked>> | 80% | 39,595 psi | 84% | 2238 fps | 99.5% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 35,737 psi | 76% | 2228 fps | 97.7% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 37,333 psi | 79% | 2136 fps | 100% |
| Somchem S355 | <<locked>> | 80% | 35,665 psi | 76% | 2185 fps | 98.2% |
| Somchem S365 | 61.2 gr | 80% | 25,846 psi | 55% | 2037 fps | 95.8% |
| Vihtavuori N150 | <<locked>> | 80% | 33,895 psi | 72% | 2133 fps | 98.9% |
| Vihtavuori N160 | <<locked>> | 82% | 32,155 psi | 68% | 2136 fps | 95% |
| Vihtavuori N540 | <<locked>> | 80% | 39,900 psi | 85% | 2234 fps | 100% |
| Vihtavuori N550 | <<locked>> | 84% | 33,779 psi | 72% | 2185 fps | 95.4% |
| Vihtavuori N555 | <<locked>> | 90% | 30,269 psi | 64% | 2172 fps | 95.2% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 30,110 psi | 64% | 2070 fps | 96.4% |
| Winchester StaBALL HD | <<locked>> | 94% | 28,326 psi | 60% | 2169 fps | 95.4% |
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 39 powders for .375 Fl. Mag. N.E. loaded with the .375 | 300gr | Woodleigh RN SN. Alliant Reloder-26 delivers the highest muzzle velocity at 2,480 fps; across all powders the maximum-charge window runs from 1,486 fps to 2,480 fps. Accurate 3100 gives the best case fill at 100 %, and 39 of the 39 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (325 MPa), the top charges use 73–90 %, leaving at least 10 % headroom. The 300.0 gr projectile in 0.375" calls for a 1:6.0 twist; slower twists will usually not stabilise this weight. Accurate 3100, Alliant Reloder-23, Alliant Reloder-26 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 Reloder-26, Somchem S365, ReloadSwiss RS 70 rank at the top here: for .375 Fl. Mag. N.E. with the .375 | 300gr | Woodleigh RN SN 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.