Load Specifications
Load data in caliber 10.3 x 60 R Swiss with .41 | 240gr | Rim Rock SWC?FB bullet and 14 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Alliant AR-Comp, Accurate 2495 and Vihtavuori N135.
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 ≥ 80% and propellant combustion ≥ 95%. 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: 23.62"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2015 | <<locked>> | 88% | 34,809 psi | 89% | 2543 fps | 98% |
| Accurate 2495 | <<locked>> | 96% | 33,373 psi | 85% | 2589 fps | 98.1% |
| Alliant AR-Comp | <<locked>> | 90% | 34,374 psi | 88% | 2618 fps | 99.7% |
| Alliant Reloder-10x | <<locked>> | 82% | 33,228 psi | 85% | 2523 fps | 98.5% |
| Hodgdon H322 | <<locked>> | 84% | 34,577 psi | 88% | 2569 fps | 96.2% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 31,647 psi | 81% | 1713 fps | 100% |
| IMR 3031 | <<locked>> | 92% | 34,824 psi | 89% | 2638 fps | 97.2% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 31,488 psi | 80% | 1752 fps | 100% |
| SNPE Vectan SP 3 | <<locked>> | 82% | 34,272 psi | 88% | 2533 fps | 97.1% |
| SNPE Vectan Tubal 5000 | <<locked>> | 96% | 35,114 psi | 90% | 2510 fps | 96.3% |
| Somchem S335 | <<locked>> | 90% | 34,925 psi | 89% | 2516 fps | 96.2% |
| Vihtavuori N130 | <<locked>> | 84% | 34,258 psi | 87% | 2490 fps | 98.5% |
| Vihtavuori N133 | <<locked>> | 88% | 33,721 psi | 86% | 2487 fps | 97.5% |
| Vihtavuori N135 | <<locked>> | 94% | 33,518 psi | 86% | 2569 fps | 97.9% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 23.62"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2015 | <<locked>> | 80% | 26,556 psi | 68% | 2336 fps | 95% |
| Accurate 2495 | 70.1 gr | 90% | 26,774 psi | 68% | 2421 fps | 95.7% |
| Alliant AR-Comp | 61.6 gr | 80% | 24,511 psi | 63% | 2343 fps | 96.6% |
| Alliant Reloder-10x | <<locked>> | 80% | 31,082 psi | 79% | 2467 fps | 97.9% |
| Hodgdon H322 | <<locked>> | 82% | 32,314 psi | 83% | 2510 fps | 95.3% |
| Hodgdon TrailBoss | <<locked>> | 80% | 23,177 psi | 59% | 1529 fps | 100% |
| IMR 3031 | <<locked>> | 88% | 30,487 psi | 78% | 2526 fps | 95.5% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 22,887 psi | 58% | 1565 fps | 100% |
| SNPE Vectan SP 3 | <<locked>> | 80% | 32,068 psi | 82% | 2480 fps | 96.3% |
| SNPE Vectan Tubal 5000 | <<locked>> | 94% | 32,967 psi | 84% | 2464 fps | 95.6% |
| Somchem S335 | <<locked>> | 88% | 32,837 psi | 84% | 2467 fps | 95.4% |
| Vihtavuori N130 | <<locked>> | 80% | 30,081 psi | 77% | 2388 fps | 97.4% |
| Vihtavuori N133 | <<locked>> | 82% | 27,818 psi | 71% | 2336 fps | 95.3% |
| Vihtavuori N135 | 66.3 gr | 88% | 27,499 psi | 70% | 2411 fps | 95.6% |
Recommended = one of the top powders for this cartridge and bullet combination.
ᴾ possible press load - work up slowly to this load while watching for signs of excessive pressure.
This overview compares 39 powders for 10.3 x 60 R Swiss loaded with the .41 | 240gr | Rim Rock SWC?FB. IMR 3031 delivers the highest muzzle velocity at 2,638 fps; across all powders the maximum-charge window runs from 1,713 fps to 2,638 fps. Hodgdon TrailBoss gives the best case fill at 100 %, and 39 of the 39 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (270 MPa), the top charges use 80–90 %, leaving at least 10 % headroom. Hodgdon TrailBoss, ReloadSwiss RS 14, Vihtavuori N150 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. Alliant AR-Comp, Accurate 2495, Vihtavuori N135 rank at the top here: for 10.3 x 60 R Swiss with the .41 | 240gr | Rim Rock SWC?FB they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, Accurate 2520, ADI Benchmark 8208, Alliant Reloder- TS 15.5 burn incompletely and react more sensitively to barrel length and temperature. Always begin at the start load and work up in small increments while checking case and primer for pressure signs.