Load Specifications
Load data in caliber .32 H&R Mag. with .313 | 100gr | Rim Rock RNFP Cowboy bullet and 9 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% | 17,390 psi | 86% | 958 fps | 95.5% |
| Baschieri & Pellagri 102 Pistol² | <<locked>> | 72% | 16,853 psi | 83% | 906 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 13,953 psi | 69% | 810 fps | 100% |
| Maxam CSB 1² | <<locked>> | 64% | 18,289 psi | 90% | 942 fps | 99.7% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 12,923 psi | 64% | 810 fps | 99.9% |
| ReloadSwiss RS 20² | <<locked>> | 64% | 17,550 psi | 86% | 981 fps | 97.6% |
| Vihtavuori 3N37*² | <<locked>> | 64% | 17,651 psi | 87% | 978 fps | 88.5% |
| Vihtavuori N32C Tin Star | <<locked>> | 80% | 17,593 psi | 87% | 869 fps | 100% |
| Vihtavuori N350*² | <<locked>> | 68% | 16,694 psi | 82% | 955 fps | 87.9% |
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% | 12,749 psi | 63% | 837 fps | 90.4% |
| Baschieri & Pellagri 102 Pistol² | <<locked>> | 60% | 11,864 psi | 58% | 794 fps | 99.8% |
| Hodgdon TrailBoss² | 1.9 gr | 60% | 6,425 psi | 32% | 584 fps | 97% |
| Maxam CSB 1² | <<locked>> | 60% | 16,520 psi | 81% | 906 fps | 99.2% |
| ReloadSwiss RS 14*² | 2 gr | 60% | 6,266 psi | 31% | 587 fps | 92.4% |
| ReloadSwiss RS 20² | <<locked>> | 60% | 15,142 psi | 75% | 922 fps | 95.7% |
| Vihtavuori 3N37*² | <<locked>> | 60% | 15,519 psi | 76% | 925 fps | 86% |
| Vihtavuori N32C Tin Star² | <<locked>> | 60% | 10,660 psi | 53% | 725 fps | 100% |
| Vihtavuori N350*² | <<locked>> | 64% | 15,229 psi | 75% | 919 fps | 86.1% |
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 9 powders for .32 H&R Mag. loaded with the .313 | 100gr | Rim Rock RNFP Cowboy. ReloadSwiss RS 20 delivers the highest muzzle velocity at 981 fps; across all powders the maximum-charge window runs from 810 fps to 981 fps. Hodgdon TrailBoss gives the best case fill at 100 %, and 3 of the 9 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (140 MPa), the top charges use 64–90 %, 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 | 100gr | Rim Rock RNFP Cowboy they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, 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.