Load Specifications
Load data in caliber .357 Mag. with .358 | 120gr | Rim Rock TC Cowboy bullet and 68 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Rottweil P 806, SNPE Vectan BA7 1/2 and Vihtavuori N350.
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: 6"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate No. 2² | <<locked>> | 76% | 36,593 psi | 84% | 1490 fps | 100% |
| Accurate No. 5² | <<locked>> | 64% | 39,305 psi | 90% | 1624 fps | 99.4% |
| Accurate No. 7* | <<locked>> | 80% | 39,073 psi | 90% | 1677 fps | 91.5% |
| Accurate Solo 1000 | <<locked>> | 80% | 38,522 psi | 89% | 1407 fps | 100% |
| Accurate Solo 1250 | <<locked>> | 84% | 38,000 psi | 87% | 1467 fps | 100% |
| ADI AP 100ᴾ | <<locked>> | 100% | 37,579 psi | 86% | 1598 fps | 98.2% |
| ADI AP 70N² | <<locked>> | 68% | 36,071 psi | 83% | 1460 fps | 100% |
| ADI APS 350² | <<locked>> | 76% | 37,420 psi | 86% | 1276 fps | 100% |
| ADI APS 450 | <<locked>> | 80% | 39,204 psi | 90% | 1335 fps | 100% |
| ADI AS 30 | <<locked>> | 80% | 37,739 psi | 87% | 1365 fps | 100% |
| ADI AS 50N² | <<locked>> | 76% | 37,652 psi | 87% | 1414 fps | 100% |
| Alliant BE-86 | <<locked>> | 80% | 36,434 psi | 84% | 1430 fps | 100% |
| Alliant BLUE DOT*ᴾ | <<locked>> | 100% | 35,868 psi | 82% | 1614 fps | 88.9% |
| Alliant BULLSEYE² | <<locked>> | 72% | 36,201 psi | 83% | 1522 fps | 100% |
| Alliant Green Dot | <<locked>> | 80% | 38,014 psi | 87% | 1424 fps | 100% |
| Alliant Hercoᴾ | <<locked>> | 100% | 38,479 psi | 88% | 1552 fps | 100% |
| Alliant POWER PISTOL | <<locked>> | 84% | 39,001 psi | 90% | 1673 fps | 98.1% |
| Alliant RED DOT | <<locked>> | 80% | 36,593 psi | 84% | 1375 fps | 100% |
| Alliant Sport Pistol² | <<locked>> | 68% | 36,854 psi | 85% | 1532 fps | 100% |
| Alliant UNIQUE | <<locked>> | 84% | 38,189 psi | 88% | 1555 fps | 100% |
| Baschieri & Pellagri 100 | <<locked>> | 80% | 38,203 psi | 88% | 1407 fps | 100% |
| Baschieri & Pellagri 102 Pistolᴾ | <<locked>> | 100% | 38,406 psi | 88% | 1421 fps | 100% |
| Baschieri & Pellagri 103 Pistol² | <<locked>> | 72% | 35,070 psi | 81% | 1391 fps | 100% |
| Hodgdon CFE Pistol | <<locked>> | 80% | 38,493 psi | 88% | 1483 fps | 100% |
| Hodgdon Clays | <<locked>> | 88% | 37,492 psi | 86% | 1312 fps | 100% |
| Hodgdon HS-6² | <<locked>> | 68% | 37,550 psi | 86% | 1578 fps | 99.8% |
| Hodgdon Longshot² | <<locked>> | 64% | 36,172 psi | 83% | 1552 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 15,983 psi | 37% | 1024 fps | 100% |
| Hodgdon Universal² | <<locked>> | 76% | 36,970 psi | 85% | 1470 fps | 100% |
| Lovex D036² | <<locked>> | 64% | 39,247 psi | 90% | 1627 fps | 99.4% |
| Lovex D037.1* | <<locked>> | 80% | 39,073 psi | 90% | 1677 fps | 91.5% |
| Lovex S011² | <<locked>> | 68% | 37,246 psi | 86% | 1424 fps | 100% |
| Lovex S020² | <<locked>> | 76% | 38,522 psi | 89% | 1506 fps | 100% |
| Maxam CSB 1 | <<locked>> | 88% | 38,247 psi | 88% | 1463 fps | 100% |
| Maxam CSB 2 | <<locked>> | 84% | 38,914 psi | 89% | 1473 fps | 100% |
| Maxam CSB 3 | <<locked>> | 80% | 35,984 psi | 83% | 1411 fps | 100% |
| Maxam CSB 4 | <<locked>> | 80% | 38,856 psi | 89% | 1421 fps | 100% |
| Maxam CSB 5² | <<locked>> | 76% | 38,769 psi | 89% | 1365 fps | 100% |
| Ramshot Silhouette² | <<locked>> | 68% | 36,506 psi | 84% | 1529 fps | 100% |
| Ramshot True Blue² | <<locked>> | 64% | 37,405 psi | 86% | 1562 fps | 100% |
| ReloadSwiss RS 12² | <<locked>> | 72% | 37,927 psi | 87% | 1444 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 14,997 psi | 34% | 1037 fps | 100% |
| ReloadSwiss RS 20 | <<locked>> | 84% | 36,405 psi | 84% | 1522 fps | 100% |
| ReloadSwiss RS 24* | <<locked>> | 84% | 35,969 psi | 83% | 1614 fps | 92.5% |
| Rottweil P 801² | <<locked>> | 68% | 38,290 psi | 88% | 1411 fps | 100% |
| Rottweil P 806 | <<locked>> | 88% | 34,650 psi | 80% | 1624 fps | 99.8% |
| Shooters World Auto Pistol² | <<locked>> | 64% | 39,247 psi | 90% | 1627 fps | 99.4% |
| Shooters World Major Pistol* | <<locked>> | 80% | 39,073 psi | 90% | 1677 fps | 91.5% |
| SNPE Vectan A0 | <<locked>> | 88% | 38,493 psi | 88% | 1506 fps | 100% |
| SNPE Vectan A1² | <<locked>> | 76% | 36,201 psi | 83% | 1424 fps | 100% |
| SNPE Vectan BA 9 | <<locked>> | 80% | 39,204 psi | 90% | 1480 fps | 100% |
| SNPE Vectan BA10² | <<locked>> | 72% | 36,463 psi | 84% | 1302 fps | 100% |
| SNPE Vectan BA7 1/2 | <<locked>> | 92% | 38,072 psi | 88% | 1562 fps | 100% |
| SNPE Vectan BA9 1/2 | <<locked>> | 80% | 38,435 psi | 88% | 1480 fps | 100% |
| SNPE Vectan SP 2 | <<locked>> | 80% | 39,291 psi | 90% | 1683 fps | 99.2% |
| Somchem MP200² | <<locked>> | 76% | 36,970 psi | 85% | 1526 fps | 100% |
| Somchem MS200 | <<locked>> | 80% | 35,694 psi | 82% | 1483 fps | 100% |
| Somchem S221² | <<locked>> | 72% | 38,058 psi | 87% | 1624 fps | 96.1% |
| Vihtavuori 3N37 | <<locked>> | 84% | 37,550 psi | 86% | 1578 fps | 100% |
| Vihtavuori 3N38*ᴾ | <<locked>> | 100% | 38,435 psi | 88% | 1640 fps | 94.3% |
| Vihtavuori N105ᴾ | <<locked>> | 100% | 32,532 psi | 75% | 1611 fps | 95.9% |
| Vihtavuori N320² | <<locked>> | 76% | 38,116 psi | 88% | 1417 fps | 100% |
| Vihtavuori N32C Tin Starᴾ | <<locked>> | 100% | 29,602 psi | 68% | 1234 fps | 100% |
| Vihtavuori N330² | <<locked>> | 76% | 37,724 psi | 87% | 1476 fps | 100% |
| Vihtavuori N340 | <<locked>> | 80% | 35,969 psi | 83% | 1490 fps | 100% |
| Vihtavuori N350 | <<locked>> | 88% | 36,201 psi | 83% | 1555 fps | 100% |
| Winchester 231² | <<locked>> | 64% | 35,157 psi | 81% | 1417 fps | 100% |
| Winchester AutoComp | <<locked>> | 84% | 37,333 psi | 86% | 1473 fps | 100% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 6"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate No. 2² | <<locked>> | 60% | 22,669 psi | 52% | 1266 fps | 99.5% |
| Accurate No. 5² | <<locked>> | 60% | 34,011 psi | 78% | 1545 fps | 98.5% |
| Accurate No. 7*² | <<locked>> | 72% | 29,544 psi | 68% | 1519 fps | 86.7% |
| Accurate Solo 1000² | <<locked>> | 60% | 23,917 psi | 55% | 1201 fps | 100% |
| Accurate Solo 1250² | <<locked>> | 60% | 19,986 psi | 46% | 1188 fps | 100% |
| ADI AP 100*² | <<locked>> | 68% | 16,665 psi | 38% | 1171 fps | 86.1% |
| ADI AP 70N² | <<locked>> | 60% | 29,037 psi | 67% | 1358 fps | 100% |
| ADI APS 350² | <<locked>> | 60% | 25,918 psi | 60% | 1122 fps | 100% |
| ADI APS 450² | <<locked>> | 60% | 24,352 psi | 56% | 1132 fps | 100% |
| ADI AS 30² | <<locked>> | 60% | 23,699 psi | 54% | 1165 fps | 100% |
| ADI AS 50N² | <<locked>> | 60% | 25,512 psi | 59% | 1243 fps | 100% |
| Alliant BE-86² | <<locked>> | 60% | 20,378 psi | 47% | 1188 fps | 100% |
| Alliant BLUE DOT* | <<locked>> | 96% | 32,605 psi | 75% | 1558 fps | 87.2% |
| Alliant BULLSEYE² | <<locked>> | 60% | 26,063 psi | 60% | 1358 fps | 100% |
| Alliant Green Dot² | <<locked>> | 60% | 23,090 psi | 53% | 1204 fps | 100% |
| Alliant Herco² | <<locked>> | 60% | 14,663 psi | 34% | 1093 fps | 97.4% |
| Alliant POWER PISTOL*² | <<locked>> | 60% | 19,174 psi | 44% | 1270 fps | 87.6% |
| Alliant RED DOT² | <<locked>> | 60% | 22,640 psi | 52% | 1168 fps | 100% |
| Alliant Sport Pistol² | <<locked>> | 60% | 28,979 psi | 67% | 1414 fps | 100% |
| Alliant UNIQUE² | <<locked>> | 60% | 20,233 psi | 47% | 1247 fps | 99.7% |
| Baschieri & Pellagri 100² | <<locked>> | 60% | 22,365 psi | 51% | 1184 fps | 100% |
| Baschieri & Pellagri 102 Pistol² | <<locked>> | 60% | 14,286 psi | 33% | 1033 fps | 100% |
| Baschieri & Pellagri 103 Pistol² | <<locked>> | 60% | 24,018 psi | 55% | 1237 fps | 100% |
| Hodgdon CFE Pistol² | <<locked>> | 60% | 22,423 psi | 52% | 1243 fps | 100% |
| Hodgdon Clays² | <<locked>> | 60% | 20,537 psi | 47% | 1066 fps | 100% |
| Hodgdon HS-6² | <<locked>> | 60% | 28,050 psi | 64% | 1424 fps | 98% |
| Hodgdon Longshot² | <<locked>> | 60% | 31,270 psi | 72% | 1476 fps | 99.6% |
| Hodgdon TrailBoss² | <<locked>> | 60% | 7,498 psi | 17% | 764 fps | 100% |
| Hodgdon Universal² | <<locked>> | 60% | 24,192 psi | 56% | 1276 fps | 100% |
| Lovex D036² | <<locked>> | 60% | 34,011 psi | 78% | 1545 fps | 98.4% |
| Lovex D037.1*² | <<locked>> | 72% | 29,544 psi | 68% | 1519 fps | 86.7% |
| Lovex S011² | <<locked>> | 60% | 29,530 psi | 68% | 1322 fps | 100% |
| Lovex S020² | <<locked>> | 60% | 23,453 psi | 54% | 1286 fps | 100% |
| Maxam CSB 1² | <<locked>> | 60% | 19,145 psi | 44% | 1161 fps | 100% |
| Maxam CSB 2² | <<locked>> | 60% | 20,160 psi | 46% | 1194 fps | 100% |
| Maxam CSB 3² | <<locked>> | 60% | 21,741 psi | 50% | 1194 fps | 100% |
| Maxam CSB 4² | <<locked>> | 60% | 23,482 psi | 54% | 1204 fps | 100% |
| Maxam CSB 5² | <<locked>> | 60% | 26,513 psi | 61% | 1204 fps | 100% |
| Ramshot Silhouette² | <<locked>> | 60% | 28,036 psi | 64% | 1401 fps | 100% |
| Ramshot True Blue² | <<locked>> | 60% | 32,416 psi | 75% | 1490 fps | 99.8% |
| ReloadSwiss RS 12² | <<locked>> | 60% | 26,643 psi | 61% | 1293 fps | 100% |
| ReloadSwiss RS 14² | <<locked>> | 60% | 7,136 psi | 16% | 764 fps | 98.4% |
| ReloadSwiss RS 20² | <<locked>> | 60% | 18,144 psi | 42% | 1211 fps | 100% |
| ReloadSwiss RS 24*² | <<locked>> | 72% | 24,932 psi | 57% | 1407 fps | 86.1% |
| Rottweil P 801² | <<locked>> | 60% | 30,081 psi | 69% | 1306 fps | 100% |
| Rottweil P 806*² | 10 gr | 60% | 13,053 psi | 30% | 1142 fps | 86.9% |
| Shooters World Auto Pistol² | <<locked>> | 60% | 34,011 psi | 78% | 1545 fps | 98.4% |
| Shooters World Major Pistol*² | <<locked>> | 72% | 29,544 psi | 68% | 1519 fps | 86.7% |
| SNPE Vectan A0² | <<locked>> | 60% | 18,652 psi | 43% | 1171 fps | 99.3% |
| SNPE Vectan A1² | <<locked>> | 60% | 23,728 psi | 55% | 1240 fps | 100% |
| SNPE Vectan BA 9² | <<locked>> | 60% | 22,902 psi | 53% | 1240 fps | 100% |
| SNPE Vectan BA10² | <<locked>> | 60% | 27,369 psi | 63% | 1181 fps | 100% |
| SNPE Vectan BA7 1/2*² | 7.4 gr | 60% | 16,085 psi | 37% | 1135 fps | 91.6% |
| SNPE Vectan BA9 1/2² | <<locked>> | 60% | 22,336 psi | 51% | 1237 fps | 100% |
| SNPE Vectan SP 2*² | <<locked>> | 60% | 20,479 psi | 47% | 1325 fps | 91.1% |
| Somchem MP200² | <<locked>> | 60% | 23,163 psi | 53% | 1299 fps | 99.9% |
| Somchem MS200² | <<locked>> | 60% | 21,306 psi | 49% | 1240 fps | 100% |
| Somchem S221*² | <<locked>> | 60% | 25,179 psi | 58% | 1391 fps | 89.9% |
| Vihtavuori 3N37*² | <<locked>> | 60% | 18,376 psi | 42% | 1224 fps | 94.9% |
| Vihtavuori 3N38* | <<locked>> | 84% | 24,816 psi | 57% | 1401 fps | 87.2% |
| Vihtavuori N105* | <<locked>> | 84% | 20,117 psi | 46% | 1352 fps | 87.5% |
| Vihtavuori N320² | <<locked>> | 60% | 24,482 psi | 56% | 1230 fps | 100% |
| Vihtavuori N32C Tin Star² | <<locked>> | 60% | 12,502 psi | 29% | 925 fps | 100% |
| Vihtavuori N330² | <<locked>> | 60% | 23,453 psi | 54% | 1273 fps | 100% |
| Vihtavuori N340² | <<locked>> | 60% | 20,523 psi | 47% | 1230 fps | 99.9% |
| Vihtavuori N350*² | 7.2 gr | 60% | 15,737 psi | 36% | 1148 fps | 93% |
| Winchester 231² | <<locked>> | 60% | 31,198 psi | 72% | 1365 fps | 100% |
| Winchester AutoComp ² | <<locked>> | 60% | 19,682 psi | 45% | 1194 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 22 powders for .357 Mag. loaded with the .358 | 120gr | Rim Rock TC Cowboy. Alliant POWER PISTOL delivers the highest muzzle velocity at 1,673 fps; across all powders the maximum-charge window runs from 1,024 fps to 1,673 fps. ADI AP 100 gives the best case fill at 100 %, and 22 of the 22 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (300 MPa), the top charges use 34–90 %, leaving at least 10 % headroom. ADI AP 100, Alliant Herco, Baschieri & Pellagri 102 Pistol 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. Rottweil P 806, SNPE Vectan BA7 1/2, Vihtavuori N350 rank at the top here: for .357 Mag. with the .358 | 120gr | Rim Rock TC Cowboy they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, ReloadSwiss RS 24, Vihtavuori 3N38 burn incompletely and react more sensitively to barrel length and temperature. Hodgdon TrailBoss, ReloadSwiss RS 14, Vihtavuori N32C Tin Star 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.