Load Specifications
Load data in caliber 9 x 21 with .357 | 125gr | X-TREME FP bullet and 58 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are ReloadSwiss RS 20, Alliant UNIQUE and Maxam CSB 2.
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: 4.5"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate No. 2 | <<locked>> | 80% | 29,936 psi | 88% | 1115 fps | 97.5% |
| Accurate No. 5*² | <<locked>> | 68% | 30,530 psi | 90% | 1188 fps | 90.2% |
| Accurate Solo 1000 | <<locked>> | 80% | 30,037 psi | 88% | 1060 fps | 100% |
| Accurate Solo 1250 | <<locked>> | 88% | 29,602 psi | 87% | 1109 fps | 100% |
| ADI AP 70N² | <<locked>> | 72% | 29,472 psi | 86% | 1122 fps | 100% |
| ADI APS 350² | <<locked>> | 72% | 28,326 psi | 83% | 942 fps | 100% |
| ADI APS 450² | <<locked>> | 76% | 29,617 psi | 87% | 988 fps | 100% |
| ADI AS 30 | <<locked>> | 80% | 29,602 psi | 87% | 1030 fps | 100% |
| ADI AS 50N² | <<locked>> | 76% | 29,167 psi | 86% | 1066 fps | 100% |
| Alliant BE-86 | <<locked>> | 84% | 28,253 psi | 83% | 1089 fps | 100% |
| Alliant BULLSEYE² | <<locked>> | 76% | 28,703 psi | 84% | 1142 fps | 99.4% |
| Alliant Green Dot | <<locked>> | 80% | 28,761 psi | 84% | 1063 fps | 100% |
| Alliant Hercoᴾ | <<locked>> | 100% | 26,977 psi | 79% | 1122 fps | 98.7% |
| Alliant RED DOT | <<locked>> | 80% | 28,456 psi | 83% | 1037 fps | 100% |
| Alliant Sport Pistol² | <<locked>> | 72% | 30,095 psi | 88% | 1165 fps | 99.3% |
| Alliant UNIQUE | <<locked>> | 88% | 29,486 psi | 87% | 1165 fps | 99.3% |
| Baschieri & Pellagri 100 | <<locked>> | 80% | 28,311 psi | 83% | 1047 fps | 100% |
| Baschieri & Pellagri 102 Pistolᴾ | <<locked>> | 100% | 27,485 psi | 81% | 1063 fps | 100% |
| Baschieri & Pellagri 103 Pistol | <<locked>> | 80% | 30,429 psi | 89% | 1102 fps | 100% |
| Hodgdon CFE Pistol² | <<locked>> | 64% | 30,081 psi | 88% | 1132 fps | 100% |
| Hodgdon Clays | <<locked>> | 84% | 28,268 psi | 83% | 971 fps | 100% |
| Hodgdon HS-6*² | <<locked>> | 72% | 28,892 psi | 85% | 1152 fps | 91.6% |
| Hodgdon Longshot*² | <<locked>> | 68% | 27,644 psi | 81% | 1135 fps | 93% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 12,546 psi | 37% | 761 fps | 100% |
| Hodgdon Universal | <<locked>> | 80% | 29,472 psi | 86% | 1122 fps | 100% |
| Lovex D036*² | <<locked>> | 68% | 30,632 psi | 90% | 1188 fps | 90.2% |
| Lovex S011² | <<locked>> | 68% | 27,398 psi | 80% | 1053 fps | 100% |
| Lovex S020 | <<locked>> | 80% | 29,457 psi | 86% | 1132 fps | 99.9% |
| Maxam CSB 1 | <<locked>> | 92% | 30,269 psi | 89% | 1115 fps | 100% |
| Maxam CSB 2 | <<locked>> | 88% | 28,921 psi | 85% | 1122 fps | 100% |
| Maxam CSB 3 | <<locked>> | 84% | 28,631 psi | 84% | 1076 fps | 100% |
| Maxam CSB 4 | <<locked>> | 80% | 29,443 psi | 86% | 1070 fps | 100% |
| Maxam CSB 5² | <<locked>> | 76% | 29,805 psi | 87% | 1030 fps | 100% |
| Ramshot Silhouette² | <<locked>> | 72% | 28,471 psi | 84% | 1138 fps | 97.6% |
| Ramshot True Blue*² | <<locked>> | 68% | 29,225 psi | 86% | 1152 fps | 93.8% |
| ReloadSwiss RS 12² | <<locked>> | 76% | 29,762 psi | 87% | 1115 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 11,879 psi | 35% | 764 fps | 99% |
| ReloadSwiss RS 20 | <<locked>> | 92% | 28,935 psi | 85% | 1171 fps | 99.9% |
| Rottweil P 801² | <<locked>> | 72% | 30,748 psi | 90% | 1089 fps | 100% |
| Rottweil P 806*ᴾ | <<locked>> | 100% | 27,340 psi | 80% | 1237 fps | 91.9% |
| Shooters World Auto Pistol*² | <<locked>> | 68% | 30,632 psi | 90% | 1188 fps | 90.2% |
| SNPE Vectan A0 | <<locked>> | 92% | 30,589 psi | 90% | 1132 fps | 99.3% |
| SNPE Vectan A1 | <<locked>> | 80% | 29,907 psi | 88% | 1096 fps | 100% |
| SNPE Vectan BA 9 | <<locked>> | 80% | 28,906 psi | 85% | 1093 fps | 100% |
| SNPE Vectan BA10² | <<locked>> | 72% | 29,660 psi | 87% | 991 fps | 100% |
| SNPE Vectan BA7 1/2* | <<locked>> | 96% | 28,660 psi | 84% | 1135 fps | 92.7% |
| SNPE Vectan BA9 1/2 | <<locked>> | 84% | 30,676 psi | 90% | 1129 fps | 100% |
| SNPE Vectan SP 2* | <<locked>> | 88% | 30,443 psi | 89% | 1247 fps | 89.5% |
| Somchem MP200 | <<locked>> | 80% | 29,051 psi | 85% | 1142 fps | 98.4% |
| Somchem MS200 | <<locked>> | 84% | 28,514 psi | 84% | 1119 fps | 99.5% |
| Vihtavuori 3N37* | <<locked>> | 88% | 27,847 psi | 82% | 1152 fps | 93.7% |
| Vihtavuori N320 | <<locked>> | 80% | 30,487 psi | 89% | 1093 fps | 100% |
| Vihtavuori N32C Tin Starᴾ | <<locked>> | 100% | 22,104 psi | 65% | 928 fps | 100% |
| Vihtavuori N330 | <<locked>> | 80% | 27,891 psi | 82% | 1115 fps | 100% |
| Vihtavuori N340 | <<locked>> | 88% | 30,690 psi | 90% | 1152 fps | 99.5% |
| Vihtavuori N350* | <<locked>> | 96% | 29,080 psi | 85% | 1165 fps | 94.6% |
| Winchester 231² | <<locked>> | 68% | 28,776 psi | 84% | 1089 fps | 100% |
| Winchester AutoComp | <<locked>> | 88% | 29,631 psi | 87% | 1125 fps | 100% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 4.5"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate No. 2*² | <<locked>> | 60% | 16,824 psi | 49% | 892 fps | 89.8% |
| Accurate No. 5*² | <<locked>> | 60% | 23,902 psi | 70% | 1076 fps | 85.8% |
| Accurate Solo 1000² | <<locked>> | 60% | 18,608 psi | 55% | 892 fps | 100% |
| Accurate Solo 1250² | <<locked>> | 60% | 14,765 psi | 43% | 853 fps | 96.9% |
| ADI AP 70N² | <<locked>> | 60% | 21,045 psi | 62% | 991 fps | 99.9% |
| ADI APS 350² | <<locked>> | 60% | 21,669 psi | 64% | 853 fps | 100% |
| ADI APS 450² | <<locked>> | 60% | 19,899 psi | 58% | 860 fps | 100% |
| ADI AS 30² | <<locked>> | 60% | 19,000 psi | 56% | 879 fps | 100% |
| ADI AS 50N² | <<locked>> | 60% | 19,189 psi | 56% | 915 fps | 100% |
| Alliant BE-86² | <<locked>> | 60% | 15,185 psi | 45% | 866 fps | 99% |
| Alliant BULLSEYE² | <<locked>> | 60% | 19,363 psi | 57% | 978 fps | 95.8% |
| Alliant Green Dot² | <<locked>> | 60% | 18,086 psi | 53% | 896 fps | 100% |
| Alliant Herco*² | <<locked>> | 60% | 11,719 psi | 34% | 784 fps | 86.8% |
| Alliant RED DOT² | <<locked>> | 60% | 18,144 psi | 53% | 879 fps | 100% |
| Alliant Sport Pistol² | <<locked>> | 60% | 21,524 psi | 63% | 1024 fps | 96.4% |
| Alliant UNIQUE*² | 3.5 gr | 60% | 15,287 psi | 45% | 889 fps | 91.5% |
| Baschieri & Pellagri 100² | <<locked>> | 60% | 16,882 psi | 50% | 869 fps | 99.9% |
| Baschieri & Pellagri 102 Pistol² | <<locked>> | 60% | 11,153 psi | 33% | 764 fps | 98.9% |
| Baschieri & Pellagri 103 Pistol² | <<locked>> | 60% | 17,709 psi | 52% | 919 fps | 100% |
| Hodgdon CFE Pistol² | <<locked>> | 60% | 26,760 psi | 79% | 1086 fps | 100% |
| Hodgdon Clays² | <<locked>> | 60% | 17,042 psi | 50% | 810 fps | 100% |
| Hodgdon HS-6*² | <<locked>> | 64% | 22,568 psi | 66% | 1047 fps | 87.5% |
| Hodgdon Longshot*² | <<locked>> | 60% | 21,509 psi | 63% | 1030 fps | 89% |
| Hodgdon TrailBoss² | <<locked>> | 60% | 6,889 psi | 20% | 568 fps | 96.7% |
| Hodgdon Universal² | <<locked>> | 60% | 18,405 psi | 54% | 938 fps | 99.3% |
| Lovex D036*² | <<locked>> | 60% | 23,844 psi | 70% | 1076 fps | 85.8% |
| Lovex S011² | <<locked>> | 60% | 22,785 psi | 67% | 984 fps | 100% |
| Lovex S020² | <<locked>> | 60% | 16,447 psi | 48% | 909 fps | 95.2% |
| Maxam CSB 1² | <<locked>> | 60% | 14,373 psi | 42% | 840 fps | 96.7% |
| Maxam CSB 2² | 3.3 gr | 60% | 14,605 psi | 43% | 879 fps | 99.8% |
| Maxam CSB 3² | <<locked>> | 60% | 16,389 psi | 48% | 876 fps | 99.9% |
| Maxam CSB 4² | <<locked>> | 60% | 17,376 psi | 51% | 886 fps | 100% |
| Maxam CSB 5² | <<locked>> | 60% | 19,841 psi | 58% | 896 fps | 100% |
| Ramshot Silhouette*² | <<locked>> | 60% | 20,218 psi | 59% | 1001 fps | 93.4% |
| Ramshot True Blue*² | <<locked>> | 60% | 22,814 psi | 67% | 1047 fps | 90% |
| ReloadSwiss RS 12² | <<locked>> | 60% | 19,102 psi | 56% | 958 fps | 100% |
| ReloadSwiss RS 14*² | <<locked>> | 60% | 6,599 psi | 19% | 558 fps | 91.8% |
| ReloadSwiss RS 20*² | 3.6 gr | 60% | 13,039 psi | 38% | 850 fps | 91.2% |
| Rottweil P 801² | <<locked>> | 60% | 22,727 psi | 67% | 984 fps | 100% |
| Rottweil P 806* | <<locked>> | 88% | 18,971 psi | 56% | 1086 fps | 85.3% |
| Shooters World Auto Pistol*² | <<locked>> | 60% | 23,844 psi | 70% | 1076 fps | 85.8% |
| SNPE Vectan A0*² | <<locked>> | 60% | 14,634 psi | 43% | 843 fps | 90.4% |
| SNPE Vectan A1² | <<locked>> | 60% | 17,622 psi | 52% | 902 fps | 99.4% |
| SNPE Vectan BA 9² | <<locked>> | 60% | 16,839 psi | 49% | 889 fps | 96.7% |
| SNPE Vectan BA10² | <<locked>> | 60% | 22,133 psi | 65% | 892 fps | 100% |
| SNPE Vectan BA7 1/2* | <<locked>> | 80% | 20,189 psi | 59% | 988 fps | 86.9% |
| SNPE Vectan BA9 1/2² | <<locked>> | 60% | 16,926 psi | 50% | 902 fps | 98.1% |
| SNPE Vectan SP 2* | <<locked>> | 80% | 24,468 psi | 72% | 1148 fps | 85.6% |
| Somchem MP200*² | <<locked>> | 60% | 17,390 psi | 51% | 928 fps | 92% |
| Somchem MS200*² | <<locked>> | 60% | 15,867 psi | 47% | 883 fps | 93.2% |
| Vihtavuori 3N37*² | <<locked>> | 72% | 18,449 psi | 54% | 981 fps | 86.9% |
| Vihtavuori N320² | <<locked>> | 60% | 17,782 psi | 52% | 909 fps | 100% |
| Vihtavuori N32C Tin Star² | <<locked>> | 60% | 10,269 psi | 30% | 699 fps | 100% |
| Vihtavuori N330² | <<locked>> | 60% | 15,940 psi | 47% | 915 fps | 99% |
| Vihtavuori N340*² | <<locked>> | 60% | 14,779 psi | 43% | 866 fps | 91.4% |
| Vihtavuori N350*² | <<locked>> | 76% | 17,506 psi | 51% | 958 fps | 86.2% |
| Winchester 231² | <<locked>> | 60% | 23,293 psi | 68% | 1010 fps | 100% |
| Winchester AutoComp ² | <<locked>> | 60% | 14,808 psi | 43% | 860 fps | 95.9% |
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 58 powders for 9 x 21 loaded with the .357 | 125gr | X-TREME FP. SNPE Vectan SP 2 delivers the highest muzzle velocity at 1,247 fps; across all powders the maximum-charge window runs from 761 fps to 1,247 fps. Alliant Herco gives the best case fill at 100 %, and 38 of the 58 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (235 MPa), the top charges use 35–90 %, leaving at least 10 % headroom. Alliant Herco, Baschieri & Pellagri 102 Pistol, Hodgdon TrailBoss 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 20, Alliant UNIQUE, Maxam CSB 2 rank at the top here: for 9 x 21 with the .357 | 125gr | X-TREME FP they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, Accurate No. 5, Hodgdon HS-6, Hodgdon Longshot burn incompletely and react more sensitively to barrel length and temperature. Accurate No. 2, Accurate No. 5, Accurate Solo 1000 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.