Load Specifications
Load data in caliber .32 H&R Mag. with .313 | 78gr | Rim Rock RN Cowboy 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 Herco*² | <<locked>> | 76% | 17,912 psi | 88% | 1122 fps | 92.8% |
| Alliant UNIQUE*² | <<locked>> | 64% | 18,173 psi | 90% | 1132 fps | 92.9% |
| Baschieri & Pellagri 102 Pistol² | <<locked>> | 76% | 17,898 psi | 88% | 1086 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 13,402 psi | 66% | 942 fps | 100% |
| Maxam CSB 1² | <<locked>> | 64% | 17,027 psi | 84% | 1073 fps | 97.7% |
| Maxam CSB 2² | <<locked>> | 64% | 18,318 psi | 90% | 1125 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 11,748 psi | 58% | 912 fps | 98% |
| ReloadSwiss RS 20*² | <<locked>> | 64% | 16,302 psi | 80% | 1102 fps | 93.6% |
| SNPE Vectan A0*² | <<locked>> | 64% | 17,550 psi | 86% | 1086 fps | 92.5% |
| Vihtavuori N32C Tin Star | <<locked>> | 84% | 17,941 psi | 88% | 1033 fps | 100% |
| Winchester AutoComp ² | <<locked>> | 64% | 18,304 psi | 90% | 1112 fps | 97.4% |
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% | 11,893 psi | 59% | 938 fps | 85.1% |
| Alliant UNIQUE*² | <<locked>> | 60% | 16,085 psi | 79% | 1076 fps | 90.8% |
| Baschieri & Pellagri 102 Pistol² | <<locked>> | 60% | 11,269 psi | 56% | 909 fps | 98% |
| Hodgdon TrailBoss*² | 2.3 gr | 60% | 6,309 psi | 31% | 679 fps | 93.8% |
| Maxam CSB 1² | <<locked>> | 60% | 15,635 psi | 77% | 1033 fps | 96.7% |
| Maxam CSB 2² | <<locked>> | 60% | 16,027 psi | 79% | 1073 fps | 99.7% |
| ReloadSwiss RS 14*² | 2.3 gr | 60% | 5,787 psi | 28% | 656 fps | 87.1% |
| ReloadSwiss RS 20*² | <<locked>> | 60% | 14,388 psi | 71% | 1047 fps | 91.2% |
| SNPE Vectan A0*² | <<locked>> | 60% | 15,563 psi | 77% | 1030 fps | 90.4% |
| Vihtavuori N32C Tin Star² | <<locked>> | 60% | 10,240 psi | 50% | 843 fps | 100% |
| Winchester AutoComp ² | <<locked>> | 60% | 15,751 psi | 78% | 1047 fps | 95.6% |
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 .32 H&R Mag. loaded with the .313 | 78gr | Rim Rock RN Cowboy. Alliant UNIQUE delivers the highest muzzle velocity at 1,132 fps; across all powders the maximum-charge window runs from 912 fps to 1,132 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 (140 MPa), the top charges use 58–90 %, 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. Hodgdon TrailBoss, ReloadSwiss RS 14 rank at the top here: for .32 H&R Mag. with the .313 | 78gr | Rim Rock RN Cowboy they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, Alliant Herco, Alliant UNIQUE, ReloadSwiss RS 20 burn incompletely and react more sensitively to barrel length and temperature. Alliant Herco, Alliant UNIQUE, 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.