Load Specifications
Load data in caliber .38 Special with .355 | 125gr | Barnes TAC-XP bullet and 11 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>> | 72% | 18,550 psi | 85% | 1010 fps | 96.1% |
| Baschieri & Pellagri 102 Pistol² | <<locked>> | 72% | 18,115 psi | 83% | 958 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 14,736 psi | 68% | 850 fps | 100% |
| Maxam CSB 1² | <<locked>> | 64% | 19,276 psi | 89% | 991 fps | 99.8% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 13,605 psi | 63% | 850 fps | 100% |
| ReloadSwiss RS 20² | <<locked>> | 64% | 18,623 psi | 86% | 1033 fps | 98% |
| SNPE Vectan A0² | <<locked>> | 64% | 19,174 psi | 88% | 997 fps | 96.4% |
| SNPE Vectan BA7 1/2*² | <<locked>> | 68% | 18,246 psi | 84% | 997 fps | 87.7% |
| Vihtavuori 3N37*² | <<locked>> | 64% | 18,275 psi | 84% | 1020 fps | 88.9% |
| Vihtavuori N32C Tin Star | <<locked>> | 80% | 18,333 psi | 84% | 909 fps | 100% |
| Vihtavuori N350*² | <<locked>> | 68% | 18,246 psi | 84% | 1017 fps | 89.3% |
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 Herco*² | <<locked>> | 60% | 13,692 psi | 63% | 886 fps | 91.5% |
| Baschieri & Pellagri 102 Pistol² | <<locked>> | 60% | 12,879 psi | 59% | 843 fps | 100% |
| Hodgdon TrailBoss² | 2.7 gr | 60% | 7,150 psi | 33% | 627 fps | 98.1% |
| Maxam CSB 1² | <<locked>> | 60% | 17,376 psi | 80% | 951 fps | 99.4% |
| ReloadSwiss RS 14*² | 2.8 gr | 60% | 6,947 psi | 32% | 623 fps | 94.1% |
| ReloadSwiss RS 20² | <<locked>> | 60% | 16,244 psi | 75% | 978 fps | 96.4% |
| SNPE Vectan A0² | <<locked>> | 60% | 17,390 psi | 80% | 958 fps | 95.2% |
| SNPE Vectan BA7 1/2*² | <<locked>> | 64% | 16,244 psi | 75% | 948 fps | 85.4% |
| Vihtavuori 3N37*² | <<locked>> | 60% | 16,230 psi | 75% | 971 fps | 86.6% |
| Vihtavuori N32C Tin Star² | <<locked>> | 60% | 11,690 psi | 54% | 771 fps | 100% |
| Vihtavuori N350*² | <<locked>> | 64% | 16,085 psi | 74% | 968 fps | 87% |
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 11 powders for .38 Special loaded with the .355 | 125gr | Barnes TAC-XP. ReloadSwiss RS 20 delivers the highest muzzle velocity at 1,033 fps; across all powders the maximum-charge window runs from 850 fps to 1,033 fps. Hodgdon TrailBoss gives the best case fill at 100 %, and 3 of the 11 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (150 MPa), the top charges use 63–89 %, leaving at least 11 % 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. Hodgdon TrailBoss, ReloadSwiss RS 14 rank at the top here: for .38 Special with the .355 | 125gr | Barnes TAC-XP they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, SNPE Vectan BA7 1/2, Vihtavuori 3N37, Vihtavuori N350 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.