Load Specifications
Load data in caliber .357 Mag. with .355 | 124gr | Speer HPSB GD bullet and 66 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% | 37,768 psi | 87% | 1473 fps | 100% |
| Accurate No. 7*² | <<locked>> | 76% | 34,795 psi | 80% | 1585 fps | 90.1% |
| Accurate Solo 1000² | <<locked>> | 76% | 35,868 psi | 82% | 1348 fps | 100% |
| Accurate Solo 1250 | <<locked>> | 84% | 38,247 psi | 88% | 1437 fps | 100% |
| Accurate TCM* | <<locked>> | 88% | 39,363 psi | 90% | 1631 fps | 87.6% |
| ADI AP 100ᴾ | <<locked>> | 100% | 38,145 psi | 88% | 1578 fps | 98.6% |
| ADI AP 70N² | <<locked>> | 68% | 36,289 psi | 83% | 1434 fps | 100% |
| ADI APS 350² | <<locked>> | 76% | 37,202 psi | 86% | 1250 fps | 100% |
| ADI APS 450 | <<locked>> | 80% | 39,131 psi | 90% | 1306 fps | 100% |
| ADI AS 30 | <<locked>> | 80% | 38,682 psi | 89% | 1348 fps | 100% |
| ADI AS 50N² | <<locked>> | 76% | 38,696 psi | 89% | 1398 fps | 100% |
| Alliant BE-86 | <<locked>> | 80% | 36,753 psi | 84% | 1407 fps | 100% |
| Alliant BLUE DOT*ᴾ | <<locked>> | 100% | 36,622 psi | 84% | 1598 fps | 89.8% |
| Alliant BULLSEYE² | <<locked>> | 72% | 36,361 psi | 84% | 1493 fps | 100% |
| Alliant Green Dot | <<locked>> | 80% | 38,101 psi | 88% | 1394 fps | 100% |
| Alliant Hercoᴾ | <<locked>> | 100% | 38,986 psi | 90% | 1526 fps | 100% |
| Alliant POWER PISTOL | <<locked>> | 80% | 34,925 psi | 80% | 1578 fps | 97.3% |
| Alliant RED DOT | <<locked>> | 80% | 36,550 psi | 84% | 1345 fps | 100% |
| Alliant Sport Pistol² | <<locked>> | 68% | 37,101 psi | 85% | 1506 fps | 100% |
| Alliant UNIQUE | <<locked>> | 84% | 38,551 psi | 89% | 1529 fps | 100% |
| Baschieri & Pellagri 100 | <<locked>> | 80% | 38,305 psi | 88% | 1381 fps | 100% |
| Baschieri & Pellagri 102 Pistolᴾ | <<locked>> | 100% | 38,725 psi | 89% | 1398 fps | 100% |
| Baschieri & Pellagri 103 Pistol² | <<locked>> | 72% | 35,418 psi | 81% | 1368 fps | 100% |
| Hodgdon CFE Pistol | <<locked>> | 80% | 38,827 psi | 89% | 1457 fps | 100% |
| Hodgdon Clays | <<locked>> | 88% | 38,319 psi | 88% | 1296 fps | 100% |
| Hodgdon HS-6² | <<locked>> | 68% | 38,072 psi | 88% | 1555 fps | 99.9% |
| Hodgdon Longshot² | <<locked>> | 64% | 36,695 psi | 84% | 1529 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 16,418 psi | 38% | 1014 fps | 100% |
| Hodgdon Universal² | <<locked>> | 76% | 37,130 psi | 85% | 1444 fps | 100% |
| Lovex D037.1*² | <<locked>> | 76% | 34,795 psi | 80% | 1585 fps | 90.1% |
| Lovex S011² | <<locked>> | 68% | 38,276 psi | 88% | 1407 fps | 100% |
| Lovex S020² | <<locked>> | 76% | 38,914 psi | 89% | 1483 fps | 100% |
| Maxam CSB 1 | <<locked>> | 88% | 39,363 psi | 90% | 1447 fps | 100% |
| Maxam CSB 2 | <<locked>> | 84% | 39,218 psi | 90% | 1447 fps | 100% |
| Maxam CSB 3 | <<locked>> | 80% | 36,999 psi | 85% | 1394 fps | 100% |
| Maxam CSB 4 | <<locked>> | 80% | 38,986 psi | 90% | 1394 fps | 100% |
| Maxam CSB 5² | <<locked>> | 72% | 35,882 psi | 82% | 1302 fps | 100% |
| Ramshot Silhouette² | <<locked>> | 68% | 36,941 psi | 85% | 1506 fps | 100% |
| Ramshot True Blue² | <<locked>> | 64% | 37,956 psi | 87% | 1542 fps | 100% |
| ReloadSwiss RS 12² | <<locked>> | 72% | 38,189 psi | 88% | 1417 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 15,011 psi | 35% | 1017 fps | 100% |
| ReloadSwiss RS 20 | <<locked>> | 84% | 37,695 psi | 87% | 1509 fps | 100% |
| ReloadSwiss RS 24* | <<locked>> | 84% | 36,651 psi | 84% | 1598 fps | 93.3% |
| Rottweil P 801² | <<locked>> | 68% | 38,493 psi | 88% | 1385 fps | 100% |
| Rottweil P 806 | <<locked>> | 88% | 35,650 psi | 82% | 1608 fps | 100% |
| Shooters World Major Pistol*² | <<locked>> | 76% | 34,795 psi | 80% | 1585 fps | 90.1% |
| SNPE Vectan A0 | <<locked>> | 84% | 35,578 psi | 82% | 1440 fps | 100% |
| SNPE Vectan A1² | <<locked>> | 76% | 37,217 psi | 86% | 1407 fps | 100% |
| SNPE Vectan BA 9² | <<locked>> | 76% | 36,230 psi | 83% | 1417 fps | 100% |
| SNPE Vectan BA10² | <<locked>> | 72% | 37,260 psi | 86% | 1286 fps | 100% |
| SNPE Vectan BA7 1/2 | <<locked>> | 92% | 38,580 psi | 89% | 1542 fps | 100% |
| SNPE Vectan BA9 1/2 | <<locked>> | 80% | 38,667 psi | 89% | 1453 fps | 100% |
| SNPE Vectan SP 2² | <<locked>> | 76% | 36,013 psi | 83% | 1604 fps | 98.8% |
| Somchem MP200² | <<locked>> | 76% | 37,304 psi | 86% | 1503 fps | 100% |
| Somchem MS200 | <<locked>> | 80% | 36,767 psi | 85% | 1470 fps | 100% |
| Somchem S221² | <<locked>> | 72% | 38,696 psi | 89% | 1604 fps | 96.6% |
| Vihtavuori 3N37 | <<locked>> | 84% | 38,130 psi | 88% | 1558 fps | 100% |
| Vihtavuori 3N38ᴾ | <<locked>> | 100% | 39,160 psi | 90% | 1624 fps | 95% |
| Vihtavuori N105ᴾ | <<locked>> | 100% | 33,301 psi | 77% | 1598 fps | 96.6% |
| Vihtavuori N320² | <<locked>> | 76% | 38,276 psi | 88% | 1391 fps | 100% |
| Vihtavuori N32C Tin Starᴾ | <<locked>> | 100% | 30,443 psi | 70% | 1217 fps | 100% |
| Vihtavuori N330² | <<locked>> | 76% | 38,087 psi | 88% | 1453 fps | 100% |
| Vihtavuori N340 | <<locked>> | 80% | 37,144 psi | 85% | 1473 fps | 100% |
| Vihtavuori N350 | <<locked>> | 88% | 36,680 psi | 84% | 1532 fps | 100% |
| Winchester 231² | <<locked>> | 64% | 35,302 psi | 81% | 1391 fps | 100% |
| Winchester AutoComp | <<locked>> | 84% | 37,623 psi | 86% | 1450 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% | 22,684 psi | 52% | 1243 fps | 99.6% |
| Accurate No. 7*² | <<locked>> | 72% | 30,226 psi | 69% | 1506 fps | 87.7% |
| Accurate Solo 1000² | <<locked>> | 60% | 23,815 psi | 55% | 1175 fps | 100% |
| Accurate Solo 1250² | <<locked>> | 60% | 20,581 psi | 47% | 1175 fps | 100% |
| Accurate TCM* | <<locked>> | 84% | 34,360 psi | 79% | 1555 fps | 85.1% |
| ADI AP 100*² | <<locked>> | 68% | 16,795 psi | 39% | 1155 fps | 86.9% |
| ADI AP 70N² | <<locked>> | 60% | 29,138 psi | 67% | 1335 fps | 100% |
| ADI APS 350² | <<locked>> | 60% | 26,440 psi | 61% | 1109 fps | 100% |
| ADI APS 450² | <<locked>> | 60% | 24,918 psi | 57% | 1119 fps | 100% |
| ADI AS 30² | <<locked>> | 60% | 23,583 psi | 54% | 1138 fps | 100% |
| ADI AS 50N² | <<locked>> | 60% | 25,454 psi | 59% | 1217 fps | 100% |
| Alliant BE-86² | <<locked>> | 60% | 21,002 psi | 48% | 1175 fps | 100% |
| Alliant BLUE DOT* | <<locked>> | 92% | 29,617 psi | 68% | 1480 fps | 86% |
| Alliant BULLSEYE² | <<locked>> | 60% | 26,092 psi | 60% | 1332 fps | 100% |
| Alliant Green Dot² | <<locked>> | 60% | 23,714 psi | 55% | 1191 fps | 100% |
| Alliant Herco² | <<locked>> | 60% | 14,692 psi | 34% | 1076 fps | 97.8% |
| Alliant POWER PISTOL*² | <<locked>> | 60% | 19,334 psi | 44% | 1257 fps | 88.4% |
| Alliant RED DOT² | <<locked>> | 60% | 23,235 psi | 53% | 1152 fps | 100% |
| Alliant Sport Pistol² | <<locked>> | 60% | 29,878 psi | 69% | 1401 fps | 100% |
| Alliant UNIQUE² | <<locked>> | 60% | 20,291 psi | 47% | 1224 fps | 99.9% |
| Baschieri & Pellagri 100² | <<locked>> | 60% | 23,047 psi | 53% | 1171 fps | 100% |
| Baschieri & Pellagri 102 Pistol² | <<locked>> | 60% | 14,257 psi | 33% | 1014 fps | 100% |
| Baschieri & Pellagri 103 Pistol² | <<locked>> | 60% | 24,758 psi | 57% | 1224 fps | 100% |
| Hodgdon CFE Pistol² | <<locked>> | 60% | 22,495 psi | 52% | 1220 fps | 100% |
| Hodgdon Clays² | <<locked>> | 60% | 21,016 psi | 48% | 1053 fps | 100% |
| Hodgdon HS-6² | <<locked>> | 60% | 29,051 psi | 67% | 1417 fps | 98.6% |
| Hodgdon Longshot² | <<locked>> | 60% | 31,662 psi | 73% | 1457 fps | 99.8% |
| Hodgdon TrailBoss² | <<locked>> | 60% | 7,673 psi | 18% | 758 fps | 100% |
| Hodgdon Universal² | <<locked>> | 60% | 24,236 psi | 56% | 1253 fps | 100% |
| Lovex D037.1*² | <<locked>> | 72% | 30,226 psi | 69% | 1506 fps | 87.7% |
| Lovex S011² | <<locked>> | 60% | 30,327 psi | 70% | 1309 fps | 100% |
| Lovex S020² | <<locked>> | 60% | 23,540 psi | 54% | 1260 fps | 100% |
| Maxam CSB 1² | <<locked>> | 60% | 19,145 psi | 44% | 1138 fps | 100% |
| Maxam CSB 2² | <<locked>> | 60% | 20,856 psi | 48% | 1184 fps | 100% |
| Maxam CSB 3² | <<locked>> | 60% | 21,698 psi | 50% | 1168 fps | 100% |
| Maxam CSB 4² | <<locked>> | 60% | 23,424 psi | 54% | 1178 fps | 100% |
| Maxam CSB 5² | <<locked>> | 60% | 26,368 psi | 61% | 1178 fps | 100% |
| Ramshot Silhouette² | <<locked>> | 60% | 28,935 psi | 67% | 1388 fps | 100% |
| Ramshot True Blue² | <<locked>> | 60% | 32,779 psi | 75% | 1467 fps | 99.9% |
| ReloadSwiss RS 12² | <<locked>> | 60% | 27,441 psi | 63% | 1276 fps | 100% |
| ReloadSwiss RS 14² | <<locked>> | 60% | 7,049 psi | 16% | 745 fps | 98.5% |
| ReloadSwiss RS 20² | <<locked>> | 60% | 18,797 psi | 43% | 1201 fps | 100% |
| ReloadSwiss RS 24*² | <<locked>> | 72% | 25,309 psi | 58% | 1394 fps | 87.1% |
| Rottweil P 801² | <<locked>> | 60% | 30,951 psi | 71% | 1293 fps | 100% |
| Rottweil P 806*² | 10 gr | 60% | 13,634 psi | 31% | 1142 fps | 88.5% |
| Shooters World Major Pistol*² | <<locked>> | 72% | 30,226 psi | 69% | 1506 fps | 87.7% |
| SNPE Vectan A0² | <<locked>> | 60% | 19,203 psi | 44% | 1161 fps | 99.6% |
| SNPE Vectan A1² | <<locked>> | 60% | 23,801 psi | 55% | 1217 fps | 100% |
| SNPE Vectan BA 9² | <<locked>> | 60% | 22,960 psi | 53% | 1217 fps | 100% |
| SNPE Vectan BA10² | <<locked>> | 60% | 27,978 psi | 64% | 1165 fps | 100% |
| SNPE Vectan BA7 1/2*² | 7.3 gr | 60% | 16,172 psi | 37% | 1115 fps | 92.2% |
| SNPE Vectan BA9 1/2² | <<locked>> | 60% | 22,365 psi | 51% | 1211 fps | 100% |
| SNPE Vectan SP 2*² | <<locked>> | 60% | 20,769 psi | 48% | 1312 fps | 92% |
| Somchem MP200² | <<locked>> | 60% | 23,264 psi | 53% | 1276 fps | 100% |
| Somchem MS200² | <<locked>> | 60% | 21,321 psi | 49% | 1217 fps | 100% |
| Somchem S221*² | <<locked>> | 60% | 25,570 psi | 59% | 1378 fps | 90.8% |
| Vihtavuori 3N37² | <<locked>> | 60% | 18,579 psi | 43% | 1204 fps | 95.5% |
| Vihtavuori 3N38* | <<locked>> | 80% | 22,191 psi | 51% | 1319 fps | 85.7% |
| Vihtavuori N105* | <<locked>> | 80% | 18,275 psi | 42% | 1280 fps | 86.1% |
| Vihtavuori N320² | <<locked>> | 60% | 25,208 psi | 58% | 1217 fps | 100% |
| Vihtavuori N32C Tin Star² | <<locked>> | 60% | 12,444 psi | 29% | 902 fps | 100% |
| Vihtavuori N330² | <<locked>> | 60% | 23,554 psi | 54% | 1250 fps | 100% |
| Vihtavuori N340² | <<locked>> | 60% | 20,566 psi | 47% | 1211 fps | 100% |
| Vihtavuori N350*² | 7.1 gr | 60% | 15,853 psi | 36% | 1132 fps | 93.6% |
| Winchester 231² | <<locked>> | 60% | 31,256 psi | 72% | 1339 fps | 100% |
| Winchester AutoComp ² | <<locked>> | 60% | 19,769 psi | 45% | 1171 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 21 powders for .357 Mag. loaded with the .355 | 124gr | Speer HPSB GD. Vihtavuori 3N38 delivers the highest muzzle velocity at 1,624 fps; across all powders the maximum-charge window runs from 1,014 fps to 1,624 fps. ADI AP 100 gives the best case fill at 100 %, and 21 of the 21 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (300 MPa), the top charges use 35–90 %, 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 .355 | 124gr | Speer HPSB GD they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, ReloadSwiss RS 24 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.