Load Specifications
Load data in caliber .38 Special with .358 | 180gr | Rim Rock TC bullet and 8 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are ReloadSwiss RS 14 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 |
|---|---|---|---|---|---|---|
| ADI AP 100*² | <<locked>> | 68% | 17,956 psi | 83% | 833 fps | 88% |
| Alliant Herco² | <<locked>> | 68% | 19,435 psi | 89% | 840 fps | 99.7% |
| Baschieri & Pellagri 102 Pistol² | <<locked>> | 68% | 19,348 psi | 89% | 787 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 17,361 psi | 80% | 725 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 16,099 psi | 74% | 728 fps | 100% |
| Rottweil P 806*² | <<locked>> | 64% | 17,419 psi | 80% | 876 fps | 92.2% |
| SNPE Vectan BA7 1/2² | <<locked>> | 64% | 19,508 psi | 90% | 846 fps | 95% |
| Vihtavuori N32C Tin Star² | <<locked>> | 76% | 19,566 psi | 90% | 741 fps | 100% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 4"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| ADI AP 100*² | <<locked>> | 64% | 15,766 psi | 72% | 787 fps | 85.5% |
| Alliant Herco² | <<locked>> | 60% | 15,838 psi | 73% | 774 fps | 98.4% |
| Baschieri & Pellagri 102 Pistol² | <<locked>> | 60% | 15,476 psi | 71% | 728 fps | 100% |
| Hodgdon TrailBoss² | 2.6 gr | 60% | 8,108 psi | 37% | 538 fps | 100% |
| ReloadSwiss RS 14² | 2.6 gr | 60% | 7,440 psi | 34% | 531 fps | 99% |
| Rottweil P 806*² | <<locked>> | 60% | 15,084 psi | 69% | 827 fps | 89.6% |
| SNPE Vectan BA7 1/2*² | <<locked>> | 60% | 17,158 psi | 79% | 804 fps | 93.1% |
| Vihtavuori N32C Tin Star² | <<locked>> | 60% | 13,503 psi | 62% | 650 fps | 100% |
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 8 powders for .38 Special loaded with the .358 | 180gr | Rim Rock TC. Rottweil P 806 delivers the highest muzzle velocity at 876 fps; across all powders the maximum-charge window runs from 725 fps to 876 fps. Hodgdon TrailBoss gives the best case fill at 100 %, and 2 of the 8 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (150 MPa), the top charges use 74–90 %, 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. ReloadSwiss RS 14, Hodgdon TrailBoss rank at the top here: for .38 Special with the .358 | 180gr | Rim Rock TC they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, ADI AP 100, Rottweil P 806 burn incompletely and react more sensitively to barrel length and temperature. ADI AP 100, 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.