Load Specifications
Load data in caliber .38 S&W (Colt N.P.) with .358 | 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 Baschieri & Pellagri 102 Pistol and 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% | 14,605 psi | 84% | 830 fps | 94.2% |
| Alliant BE-86² | <<locked>> | 68% | 14,794 psi | 85% | 843 fps | 96.9% |
| Alliant Herco* | <<locked>> | 84% | 14,939 psi | 86% | 860 fps | 87.7% |
| Alliant UNIQUE*² | <<locked>> | 72% | 15,418 psi | 89% | 873 fps | 88.2% |
| Baschieri & Pellagri 100² | <<locked>> | 64% | 15,069 psi | 87% | 814 fps | 98.2% |
| Baschieri & Pellagri 102 Pistol | <<locked>> | 84% | 14,924 psi | 86% | 846 fps | 99.5% |
| Baschieri & Pellagri 103 Pistol² | <<locked>> | 64% | 15,577 psi | 90% | 860 fps | 99.1% |
| Hodgdon CFE Pistol*² | <<locked>> | 64% | 14,388 psi | 83% | 830 fps | 93.5% |
| Hodgdon Clays² | <<locked>> | 64% | 15,592 psi | 90% | 768 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 8,963 psi | 52% | 666 fps | 97.4% |
| Hodgdon Universal² | <<locked>> | 64% | 15,258 psi | 88% | 853 fps | 95.6% |
| Lovex S020*² | <<locked>> | 64% | 14,489 psi | 83% | 840 fps | 90% |
| Maxam CSB 1*² | <<locked>> | 72% | 14,866 psi | 85% | 830 fps | 94.6% |
| Maxam CSB 2² | <<locked>> | 72% | 14,185 psi | 82% | 863 fps | 98.6% |
| Maxam CSB 3² | <<locked>> | 64% | 14,533 psi | 84% | 817 fps | 97.9% |
| Maxam CSB 4² | <<locked>> | 64% | 15,548 psi | 89% | 830 fps | 99.7% |
| ReloadSwiss RS 14*ᴾ | <<locked>> | 100% | 8,209 psi | 47% | 653 fps | 92% |
| ReloadSwiss RS 20*² | <<locked>> | 76% | 15,577 psi | 90% | 892 fps | 90.7% |
| SNPE Vectan A0*² | <<locked>> | 72% | 15,548 psi | 89% | 837 fps | 87.9% |
| SNPE Vectan BA9 1/2*² | <<locked>> | 64% | 14,388 psi | 83% | 820 fps | 93.6% |
| Somchem MS200*² | <<locked>> | 64% | 14,228 psi | 82% | 817 fps | 88% |
| Vihtavuori N320² | <<locked>> | 64% | 15,577 psi | 90% | 853 fps | 99.9% |
| Vihtavuori N32C Tin Star | <<locked>> | 96% | 15,214 psi | 87% | 814 fps | 100% |
| Vihtavuori N330² | <<locked>> | 68% | 15,621 psi | 90% | 886 fps | 96.9% |
| Vihtavuori N340*² | <<locked>> | 68% | 14,504 psi | 83% | 837 fps | 87.5% |
| Winchester AutoComp *² | <<locked>> | 68% | 14,243 psi | 82% | 830 fps | 92.5% |
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% | 11,443 psi | 66% | 748 fps | 90.2% |
| Alliant BE-86*² | <<locked>> | 60% | 11,255 psi | 65% | 755 fps | 93.2% |
| Alliant Herco* | <<locked>> | 80% | 13,605 psi | 78% | 827 fps | 85.9% |
| Alliant UNIQUE*² | <<locked>> | 68% | 13,880 psi | 80% | 833 fps | 86.2% |
| Baschieri & Pellagri 100² | <<locked>> | 60% | 13,343 psi | 77% | 774 fps | 97% |
| Baschieri & Pellagri 102 Pistol*² | 2.8 gr | 60% | 8,035 psi | 46% | 659 fps | 92.3% |
| Baschieri & Pellagri 103 Pistol² | <<locked>> | 60% | 13,518 psi | 78% | 814 fps | 98% |
| Hodgdon CFE Pistol*² | <<locked>> | 60% | 12,952 psi | 74% | 794 fps | 91.8% |
| Hodgdon Clays² | <<locked>> | 60% | 13,590 psi | 78% | 728 fps | 100% |
| Hodgdon TrailBoss*² | <<locked>> | 60% | 4,627 psi | 27% | 482 fps | 86.6% |
| Hodgdon Universal*² | <<locked>> | 60% | 13,619 psi | 78% | 814 fps | 94.1% |
| Lovex S020*² | <<locked>> | 60% | 12,894 psi | 74% | 801 fps | 87.9% |
| Maxam CSB 1*² | <<locked>> | 60% | 11,052 psi | 64% | 732 fps | 89.7% |
| Maxam CSB 2² | <<locked>> | 60% | 10,356 psi | 60% | 764 fps | 95% |
| Maxam CSB 3² | <<locked>> | 60% | 12,836 psi | 74% | 778 fps | 96.5% |
| Maxam CSB 4² | <<locked>> | 60% | 14,576 psi | 84% | 810 fps | 99.4% |
| ReloadSwiss RS 14* | <<locked>> | 80% | 6,135 psi | 35% | 568 fps | 86.5% |
| ReloadSwiss RS 20*² | <<locked>> | 68% | 12,676 psi | 73% | 814 fps | 86.5% |
| SNPE Vectan A0*² | <<locked>> | 68% | 13,996 psi | 80% | 801 fps | 85.9% |
| SNPE Vectan BA9 1/2*² | <<locked>> | 60% | 12,836 psi | 74% | 784 fps | 91.8% |
| Somchem MS200*² | <<locked>> | 60% | 12,763 psi | 73% | 781 fps | 85.9% |
| Vihtavuori N320² | <<locked>> | 60% | 13,634 psi | 78% | 810 fps | 99.2% |
| Vihtavuori N32C Tin Star² | 2.1 gr | 60% | 6,570 psi | 38% | 591 fps | 97.7% |
| Vihtavuori N330*² | <<locked>> | 60% | 12,386 psi | 71% | 807 fps | 93.6% |
| Vihtavuori N340*² | <<locked>> | 64% | 13,024 psi | 75% | 797 fps | 85.4% |
| Winchester AutoComp *² | <<locked>> | 60% | 11,081 psi | 64% | 745 fps | 88.1% |
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 4 powders for .38 S&W (Colt N.P.) loaded with the .358 | 125gr | Rim Rock SWC?FB. Baschieri & Pellagri 102 Pistol delivers the highest muzzle velocity at 846 fps; across all powders the maximum-charge window runs from 653 fps to 846 fps. Hodgdon TrailBoss gives the best case fill at 100 %, and 4 of the 4 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (120 MPa), the top charges use 47–87 %, leaving at least 13 % 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. Baschieri & Pellagri 102 Pistol, Vihtavuori N32C Tin Star rank at the top here: for .38 S&W (Colt N.P.) with the .358 | 125gr | Rim Rock SWC?FB they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, ReloadSwiss RS 14 burn incompletely and react more sensitively to barrel length and temperature. Baschieri & Pellagri 102 Pistol, Hodgdon TrailBoss, ReloadSwiss RS 14 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.