Load Specifications
Load data in caliber .38 Special with .357 | 147gr | H&N KS HS bullet and 16 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Hodgdon TrailBoss and ReloadSwiss RS 14.
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 |
|---|---|---|---|---|---|---|
| Alliant Herco² | <<locked>> | 68% | 18,275 psi | 84% | 945 fps | 98.2% |
| Alliant Herco² | <<locked>> | 68% | 19,537 psi | 90% | 961 fps | 98.9% |
| Baschieri & Pellagri 102 Pistol² | <<locked>> | 68% | 17,608 psi | 81% | 886 fps | 100% |
| Baschieri & Pellagri 102 Pistol² | <<locked>> | 68% | 19,232 psi | 88% | 902 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 15,940 psi | 73% | 820 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 17,042 psi | 78% | 830 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 14,243 psi | 65% | 817 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 15,679 psi | 72% | 830 fps | 100% |
| Rottweil P 806*² | <<locked>> | 68% | 17,767 psi | 82% | 997 fps | 89% |
| Rottweil P 806*² | <<locked>> | 68% | 19,421 psi | 89% | 1027 fps | 91% |
| SNPE Vectan BA7 1/2*² | <<locked>> | 64% | 18,028 psi | 83% | 942 fps | 91.3% |
| SNPE Vectan BA7 1/2*² | <<locked>> | 64% | 19,000 psi | 87% | 951 fps | 92.3% |
| Vihtavuori N32C Tin Star² | <<locked>> | 76% | 17,883 psi | 82% | 843 fps | 100% |
| Vihtavuori N32C Tin Star² | <<locked>> | 76% | 19,667 psi | 90% | 856 fps | 100% |
| Vihtavuori N350*² | <<locked>> | 64% | 18,391 psi | 85% | 965 fps | 93.1% |
| Vihtavuori N350*² | <<locked>> | 64% | 19,406 psi | 89% | 978 fps | 94.1% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 4"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Alliant Herco² | <<locked>> | 60% | 14,315 psi | 66% | 856 fps | 95.3% |
| Alliant Herco² | <<locked>> | 60% | 15,534 psi | 71% | 873 fps | 96.5% |
| Baschieri & Pellagri 102 Pistol² | <<locked>> | 60% | 13,909 psi | 64% | 814 fps | 100% |
| Baschieri & Pellagri 102 Pistol² | <<locked>> | 60% | 15,447 psi | 71% | 837 fps | 100% |
| Hodgdon TrailBoss² | 3.1 gr | 60% | 6,585 psi | 30% | 584 fps | 98.8% |
| Hodgdon TrailBoss² | 3.1 gr | 60% | 8,006 psi | 37% | 614 fps | 99.9% |
| ReloadSwiss RS 14*² | 3.1 gr | 60% | 6,063 psi | 28% | 574 fps | 94.2% |
| ReloadSwiss RS 14² | 3.1 gr | 60% | 7,339 psi | 34% | 604 fps | 97.4% |
| Rottweil P 806*² | <<locked>> | 64% | 14,837 psi | 68% | 928 fps | 85.1% |
| Rottweil P 806*² | <<locked>> | 64% | 16,853 psi | 77% | 968 fps | 88.1% |
| SNPE Vectan BA7 1/2*² | <<locked>> | 60% | 16,085 psi | 74% | 896 fps | 89.3% |
| SNPE Vectan BA7 1/2*² | <<locked>> | 60% | 17,071 psi | 78% | 909 fps | 90.4% |
| Vihtavuori N32C Tin Star² | <<locked>> | 60% | 11,806 psi | 54% | 728 fps | 100% |
| Vihtavuori N32C Tin Star² | <<locked>> | 60% | 13,474 psi | 62% | 748 fps | 100% |
| Vihtavuori N350*² | <<locked>> | 60% | 15,737 psi | 72% | 906 fps | 90.5% |
| Vihtavuori N350*² | <<locked>> | 60% | 16,752 psi | 77% | 919 fps | 91.7% |
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 16 powders for .38 Special loaded with the .357 | 147gr | H&N KS HS. Rottweil P 806 delivers the highest muzzle velocity at 1,027 fps; across all powders the maximum-charge window runs from 817 fps to 1,027 fps. Hodgdon TrailBoss gives the best case fill at 100 %, and 4 of the 16 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (150 MPa), the top charges use 65–90 %, leaving at least 10 % headroom. Hodgdon TrailBoss, 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. Hodgdon TrailBoss, ReloadSwiss RS 14 rank at the top here: for .38 Special with the .357 | 147gr | H&N KS HS they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, Rottweil P 806, Rottweil P 806, SNPE Vectan BA7 1/2 burn incompletely and react more sensitively to barrel length and temperature. Alliant Herco, Alliant Herco, Baschieri & Pellagri 102 Pistol 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.