Load Specifications
Load data in caliber .38 S&W (Colt N.P.) with .36 | 125gr | Rim Rock SWC?FB bullet and 26 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Vihtavuori N32C Tin Star.
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 ≥ 60% and propellant combustion ≥ 80%. 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: 4"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate Solo 1250*² | <<locked>> | 68% | 14,663 psi | 84% | 830 fps | 94.3% |
| Alliant BE-86² | <<locked>> | 68% | 14,866 psi | 85% | 843 fps | 97% |
| Alliant Herco* | <<locked>> | 84% | 15,040 psi | 86% | 860 fps | 87.8% |
| Alliant UNIQUE*² | <<locked>> | 72% | 15,505 psi | 89% | 873 fps | 88.3% |
| Baschieri & Pellagri 100² | <<locked>> | 64% | 15,142 psi | 87% | 814 fps | 98.3% |
| Baschieri & Pellagri 102 Pistol | <<locked>> | 84% | 14,228 psi | 82% | 830 fps | 99.2% |
| Baschieri & Pellagri 103 Pistol² | <<locked>> | 64% | 14,939 psi | 86% | 843 fps | 98.8% |
| Hodgdon Clays² | <<locked>> | 64% | 15,679 psi | 90% | 768 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 9,007 psi | 52% | 666 fps | 97.4% |
| Hodgdon Universal² | <<locked>> | 64% | 15,287 psi | 88% | 853 fps | 95.7% |
| Lovex S020*² | <<locked>> | 64% | 14,576 psi | 84% | 843 fps | 90.1% |
| Maxam CSB 1*² | <<locked>> | 72% | 14,924 psi | 86% | 833 fps | 94.6% |
| Maxam CSB 2² | <<locked>> | 72% | 14,257 psi | 82% | 863 fps | 98.7% |
| Maxam CSB 3² | <<locked>> | 64% | 14,591 psi | 84% | 820 fps | 97.9% |
| Maxam CSB 4² | <<locked>> | 64% | 15,606 psi | 90% | 833 fps | 99.7% |
| ReloadSwiss RS 12² | <<locked>> | 64% | 15,243 psi | 88% | 879 fps | 99.9% |
| ReloadSwiss RS 14*ᴾ | <<locked>> | 100% | 8,224 psi | 47% | 656 fps | 92% |
| ReloadSwiss RS 20*² | <<locked>> | 76% | 15,679 psi | 90% | 892 fps | 90.8% |
| SNPE Vectan A0*² | <<locked>> | 72% | 15,621 psi | 90% | 837 fps | 87.9% |
| SNPE Vectan BA9 1/2*² | <<locked>> | 64% | 14,460 psi | 83% | 823 fps | 93.7% |
| Somchem MS200*² | <<locked>> | 64% | 14,301 psi | 82% | 820 fps | 88.1% |
| Vihtavuori N320² | <<locked>> | 64% | 15,650 psi | 90% | 853 fps | 99.9% |
| Vihtavuori N32C Tin Star | <<locked>> | 96% | 15,302 psi | 88% | 817 fps | 100% |
| Vihtavuori N330² | <<locked>> | 68% | 15,693 psi | 90% | 889 fps | 96.9% |
| Vihtavuori N340*² | <<locked>> | 68% | 14,591 psi | 84% | 837 fps | 87.5% |
| Winchester AutoComp *² | <<locked>> | 68% | 13,677 psi | 79% | 814 fps | 91.8% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 4"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate Solo 1250*² | <<locked>> | 60% | 11,502 psi | 66% | 748 fps | 90.3% |
| Alliant BE-86*² | <<locked>> | 60% | 11,327 psi | 65% | 755 fps | 93.3% |
| Alliant Herco* | <<locked>> | 80% | 13,663 psi | 79% | 827 fps | 86% |
| Alliant UNIQUE*² | <<locked>> | 68% | 13,953 psi | 80% | 833 fps | 86.3% |
| Baschieri & Pellagri 100² | <<locked>> | 60% | 13,402 psi | 77% | 774 fps | 97% |
| Baschieri & Pellagri 102 Pistol*² | <<locked>> | 60% | 7,600 psi | 44% | 643 fps | 91.2% |
| Baschieri & Pellagri 103 Pistol² | <<locked>> | 60% | 13,532 psi | 78% | 814 fps | 98% |
| Hodgdon Clays² | <<locked>> | 60% | 13,648 psi | 78% | 728 fps | 100% |
| Hodgdon TrailBoss*² | <<locked>> | 60% | 4,627 psi | 27% | 482 fps | 86.5% |
| Hodgdon Universal*² | <<locked>> | 60% | 13,648 psi | 78% | 814 fps | 94.1% |
| Lovex S020*² | <<locked>> | 60% | 12,966 psi | 75% | 804 fps | 87.9% |
| Maxam CSB 1*² | <<locked>> | 60% | 11,110 psi | 64% | 735 fps | 89.8% |
| Maxam CSB 2*² | <<locked>> | 60% | 9,732 psi | 56% | 745 fps | 94% |
| Maxam CSB 3² | <<locked>> | 60% | 12,894 psi | 74% | 778 fps | 96.5% |
| Maxam CSB 4² | <<locked>> | 60% | 13,706 psi | 79% | 791 fps | 99% |
| ReloadSwiss RS 12² | <<locked>> | 60% | 13,445 psi | 77% | 840 fps | 99.5% |
| ReloadSwiss RS 14* | <<locked>> | 80% | 5,816 psi | 33% | 551 fps | 85.3% |
| ReloadSwiss RS 20*² | <<locked>> | 68% | 12,734 psi | 73% | 817 fps | 86.5% |
| SNPE Vectan A0*² | <<locked>> | 68% | 14,054 psi | 81% | 801 fps | 85.9% |
| SNPE Vectan BA9 1/2*² | <<locked>> | 60% | 12,894 psi | 74% | 784 fps | 91.8% |
| Somchem MS200*² | <<locked>> | 60% | 12,836 psi | 74% | 781 fps | 86% |
| Vihtavuori N320² | <<locked>> | 60% | 13,706 psi | 79% | 810 fps | 99.3% |
| Vihtavuori N32C Tin Star² | 2.1 gr | 60% | 6,614 psi | 38% | 594 fps | 97.7% |
| Vihtavuori N330*² | <<locked>> | 60% | 12,444 psi | 72% | 807 fps | 93.6% |
| Vihtavuori N340*² | <<locked>> | 64% | 13,068 psi | 75% | 797 fps | 85.4% |
| Winchester AutoComp *² | <<locked>> | 60% | 11,081 psi | 64% | 745 fps | 88% |
Recommended = one of the top powders for this cartridge and bullet combination.
* not dangerous but load has suboptimal powder burnt with possible characteristics such as extensive muzzle flash or inaccurate loads.
² fill rate low - you might want to consider using a filler to ensure proper ignition.
ᴾ possible press load - work up slowly to this load while watching for signs of excessive pressure.
This overview compares 26 powders for .38 S&W (Colt N.P.) loaded with the .36 | 125gr | Rim Rock SWC?FB. ReloadSwiss RS 20 delivers the highest muzzle velocity at 892 fps; across all powders the maximum-charge window runs from 656 fps to 892 fps. Hodgdon TrailBoss gives the best case fill at 100 %, and 5 of the 26 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (120 MPa), the top charges use 47–90 %, leaving at least 10 % headroom. Hodgdon TrailBoss, ReloadSwiss RS 14 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. Vihtavuori N32C Tin Star rank at the top here: for .38 S&W (Colt N.P.) with the .36 | 125gr | Rim Rock SWC?FB they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, Accurate Solo 1250, Alliant Herco, Alliant UNIQUE burn incompletely and react more sensitively to barrel length and temperature. Accurate Solo 1250, Alliant BE-86, Alliant Herco 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.