Load Specifications
Load data in caliber .38 S&W (Colt N.P.) with .358 | 158gr | LEE Mold 358-158-RF bullet and 25 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 and Hodgdon TrailBoss.
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 No. 2*² | <<locked>> | 64% | 14,968 psi | 86% | 722 fps | 88.1% |
| Accurate Solo 1250² | <<locked>> | 68% | 14,634 psi | 84% | 728 fps | 97.1% |
| Alliant BE-86² | <<locked>> | 68% | 15,142 psi | 87% | 745 fps | 99.2% |
| Alliant Herco* | <<locked>> | 84% | 15,287 psi | 88% | 768 fps | 92.1% |
| Alliant UNIQUE*² | <<locked>> | 72% | 15,563 psi | 89% | 774 fps | 92.4% |
| Baschieri & Pellagri 100² | <<locked>> | 64% | 14,794 psi | 85% | 705 fps | 99.6% |
| Baschieri & Pellagri 102 Pistol | <<locked>> | 84% | 14,649 psi | 84% | 732 fps | 100% |
| Baschieri & Pellagri 103 Pistol² | <<locked>> | 64% | 15,679 psi | 90% | 751 fps | 100% |
| Hodgdon CFE Pistol² | <<locked>> | 64% | 14,446 psi | 83% | 732 fps | 96.6% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 8,586 psi | 49% | 581 fps | 99% |
| Lovex S020*² | <<locked>> | 64% | 14,707 psi | 85% | 745 fps | 94% |
| Maxam CSB 1² | <<locked>> | 68% | 13,924 psi | 80% | 712 fps | 96.7% |
| Maxam CSB 2² | <<locked>> | 72% | 14,286 psi | 82% | 755 fps | 99.9% |
| Maxam CSB 3² | <<locked>> | 64% | 14,185 psi | 82% | 709 fps | 99.4% |
| ReloadSwiss RS 14*ᴾ | <<locked>> | 100% | 7,556 psi | 43% | 568 fps | 94.4% |
| ReloadSwiss RS 20*² | <<locked>> | 72% | 14,591 psi | 84% | 764 fps | 93.7% |
| SNPE Vectan A0*² | <<locked>> | 68% | 14,098 psi | 81% | 705 fps | 90.1% |
| SNPE Vectan BA9 1/2² | <<locked>> | 64% | 15,185 psi | 87% | 738 fps | 97.3% |
| Somchem MP200*² | <<locked>> | 64% | 15,273 psi | 88% | 751 fps | 90.3% |
| Somchem MS200*² | <<locked>> | 64% | 14,069 psi | 81% | 719 fps | 91.7% |
| Vihtavuori N320² | <<locked>> | 64% | 15,389 psi | 88% | 738 fps | 100% |
| Vihtavuori N32C Tin Star | <<locked>> | 96% | 15,258 psi | 88% | 705 fps | 100% |
| Vihtavuori N330² | <<locked>> | 64% | 14,170 psi | 81% | 748 fps | 98.3% |
| Vihtavuori N340*² | <<locked>> | 68% | 14,852 psi | 85% | 741 fps | 91.9% |
| Winchester AutoComp ² | <<locked>> | 72% | 15,418 psi | 89% | 751 fps | 96.8% |
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 No. 2*² | <<locked>> | 60% | 13,938 psi | 80% | 699 fps | 86.8% |
| Accurate Solo 1250*² | <<locked>> | 60% | 11,734 psi | 67% | 666 fps | 94.3% |
| Alliant BE-86² | <<locked>> | 60% | 11,676 psi | 67% | 673 fps | 96.8% |
| Alliant Herco*² | <<locked>> | 72% | 10,805 psi | 62% | 666 fps | 85.8% |
| Alliant UNIQUE*² | <<locked>> | 60% | 11,211 psi | 64% | 676 fps | 86.5% |
| Baschieri & Pellagri 100² | <<locked>> | 60% | 13,735 psi | 79% | 686 fps | 99.2% |
| Baschieri & Pellagri 102 Pistol*² | <<locked>> | 60% | 7,237 psi | 42% | 561 fps | 94.3% |
| Baschieri & Pellagri 103 Pistol² | <<locked>> | 60% | 13,213 psi | 76% | 705 fps | 99.5% |
| Hodgdon CFE Pistol² | <<locked>> | 60% | 12,705 psi | 73% | 696 fps | 95% |
| Hodgdon TrailBoss*² | 1.5 gr | 60% | 3,814 psi | 22% | 410 fps | 86.9% |
| Lovex S020*² | <<locked>> | 60% | 12,763 psi | 73% | 705 fps | 91.8% |
| Maxam CSB 1*² | <<locked>> | 60% | 11,269 psi | 65% | 653 fps | 93.8% |
| Maxam CSB 2² | <<locked>> | 60% | 9,732 psi | 56% | 656 fps | 97.2% |
| Maxam CSB 3² | <<locked>> | 60% | 13,169 psi | 76% | 689 fps | 98.9% |
| ReloadSwiss RS 14*² | <<locked>> | 76% | 4,670 psi | 27% | 459 fps | 85.4% |
| ReloadSwiss RS 20*² | <<locked>> | 60% | 9,921 psi | 57% | 650 fps | 86% |
| SNPE Vectan A0*² | <<locked>> | 60% | 11,618 psi | 67% | 653 fps | 86.6% |
| SNPE Vectan BA9 1/2² | <<locked>> | 60% | 13,300 psi | 76% | 699 fps | 95.7% |
| Somchem MP200*² | <<locked>> | 60% | 13,518 psi | 78% | 715 fps | 88.1% |
| Somchem MS200*² | <<locked>> | 60% | 12,314 psi | 71% | 679 fps | 89.4% |
| Vihtavuori N320² | <<locked>> | 60% | 14,228 psi | 82% | 719 fps | 100% |
| Vihtavuori N32C Tin Star² | 2 gr | 60% | 6,295 psi | 36% | 522 fps | 99.3% |
| Vihtavuori N330² | <<locked>> | 60% | 12,256 psi | 70% | 709 fps | 96.7% |
| Vihtavuori N340*² | <<locked>> | 60% | 11,342 psi | 65% | 666 fps | 87.1% |
| Winchester AutoComp *² | <<locked>> | 60% | 10,646 psi | 61% | 650 fps | 91.4% |
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 5 powders for .38 S&W (Colt N.P.) loaded with the .358 | 158gr | LEE Mold 358-158-RF. Alliant Herco delivers the highest muzzle velocity at 768 fps; across all powders the maximum-charge window runs from 568 fps to 768 fps. Hodgdon TrailBoss gives the best case fill at 100 %, and 5 of the 5 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (120 MPa), the top charges use 43–88 %, leaving at least 12 % 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, Hodgdon TrailBoss rank at the top here: for .38 S&W (Colt N.P.) with the .358 | 158gr | LEE Mold 358-158-RF they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, Alliant Herco, ReloadSwiss RS 14 burn incompletely and react more sensitively to barrel length and temperature. Alliant Herco, Baschieri & Pellagri 102 Pistol, Hodgdon TrailBoss 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.