
Load Specifications
Load data in caliber .458 Win.Mag. with .458 | 600gr | Barnes RNSP bullet and 92 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Hodgdon CFE223, Alliant Power Pro 1200-R and Somchem S321.
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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You can find more information in our FAQ: How can I use the Personalized Load Calculator?
Max Load - Barrel Length: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 1680 | <<locked>> | 84% | 53,359 psi | 86% | 1699 fps | 100% |
| Accurate 2015 | <<locked>> | 98% | 54,708 psi | 88% | 1768 fps | 100% |
| Accurate 2200 | <<locked>> | 88% | 53,505 psi | 86% | 1804 fps | 98.6% |
| Accurate 2230 | <<locked>> | 88% | 53,766 psi | 86% | 1814 fps | 98.9% |
| Accurate 2460 | <<locked>> | 94% | 53,374 psi | 86% | 1791 fps | 100% |
| Accurate 2495ᴾ | <<locked>> | 100% | 45,948 psi | 74% | 1749 fps | 100% |
| Accurate 2520 | <<locked>> | 98% | 53,650 psi | 86% | 1827 fps | 100% |
| Accurate 4064ᴾ | <<locked>> | 100% | 42,757 psi | 69% | 1742 fps | 100% |
| Accurate LT-30 | <<locked>> | 90% | 54,288 psi | 87% | 1713 fps | 100% |
| Accurate LT-32 | <<locked>> | 90% | 54,810 psi | 88% | 1726 fps | 100% |
| ADI AR 2206Hᴾ | <<locked>> | 100% | 53,447 psi | 86% | 1827 fps | 99.2% |
| ADI AR 2207 | <<locked>> | 88% | 54,752 psi | 88% | 1726 fps | 100% |
| ADI AR 2208ᴾ | <<locked>> | 100% | 45,498 psi | 73% | 1729 fps | 97.4% |
| ADI AR 2219 | <<locked>> | 92% | 56,333 psi | 90% | 1824 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 98% | 53,432 psi | 86% | 1801 fps | 99.7% |
| Alliant AR-Compᴾ | <<locked>> | 100% | 54,346 psi | 87% | 1818 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 94% | 54,259 psi | 87% | 1867 fps | 99.7% |
| Alliant Power Pro 2000-MRᴾ | <<locked>> | 100% | 49,893 psi | 80% | 1857 fps | 97.9% |
| Alliant Reloder- TS 15.5ᴾ | <<locked>> | 100% | 42,931 psi | 69% | 1739 fps | 98.6% |
| Alliant Reloder-10x | <<locked>> | 94% | 55,259 psi | 89% | 1778 fps | 100% |
| Alliant Reloder-15ᴾ | <<locked>> | 100% | 47,108 psi | 76% | 1781 fps | 98% |
| Alliant Reloder-17ᴾ | <<locked>> | 100% | 38,653 psi | 62% | 1726 fps | 96.7% |
| Alliant Reloder-7 | <<locked>> | 88% | 56,144 psi | 90% | 1739 fps | 100% |
| Baschieri & Pellagri 106 | <<locked>> | 92% | 56,028 psi | 90% | 1749 fps | 100% |
| Baschieri & Pellagri 107ᴾ | <<locked>> | 100% | 53,040 psi | 85% | 1837 fps | 98.3% |
| Bofors RP3ᴾ | <<locked>> | 100% | 42,163 psi | 68% | 1742 fps | 98.6% |
| Hodgdon Benchmark | <<locked>> | 96% | 53,272 psi | 85% | 1765 fps | 99.9% |
| Hodgdon BL-C2ᴾ | <<locked>> | 100% | 54,259 psi | 87% | 1857 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 96% | 53,272 psi | 85% | 1883 fps | 98.9% |
| Hodgdon H322 | <<locked>> | 94% | 54,505 psi | 87% | 1808 fps | 100% |
| Hodgdon H335 | <<locked>> | 94% | 55,564 psi | 89% | 1831 fps | 100% |
| Hodgdon H380ᴾ | <<locked>> | 100% | 44,904 psi | 72% | 1749 fps | 96.2% |
| Hodgdon H4198 | <<locked>> | 86% | 53,185 psi | 85% | 1716 fps | 100% |
| Hodgdon H4895ᴾ | <<locked>> | 100% | 53,722 psi | 86% | 1834 fps | 99.5% |
| Hodgdon LEVERevolutionᴾ | <<locked>> | 100% | 48,312 psi | 77% | 1818 fps | 99.3% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 33,127 psi | 53% | 1010 fps | 100% |
| Hodgdon VARGETᴾ | <<locked>> | 100% | 52,315 psi | 84% | 1804 fps | 99.3% |
| IMR 3031ᴾ | <<locked>> | 100% | 51,416 psi | 82% | 1824 fps | 100% |
| IMR 4064ᴾ | <<locked>> | 100% | 47,790 psi | 77% | 1745 fps | 98% |
| IMR 4198 | <<locked>> | 92% | 53,403 psi | 86% | 1722 fps | 100% |
| IMR 4227 | <<locked>> | 82% | 53,301 psi | 85% | 1667 fps | 100% |
| IMR 4895ᴾ | <<locked>> | 100% | 48,182 psi | 77% | 1804 fps | 98.7% |
| IMR 8208 XBR | <<locked>> | 98% | 53,432 psi | 86% | 1801 fps | 99.7% |
| Lovex D073.4 | <<locked>> | 88% | 54,172 psi | 87% | 1801 fps | 100% |
| Lovex D073.5 | <<locked>> | 94% | 53,287 psi | 85% | 1798 fps | 100% |
| Lovex D073.6ᴾ | <<locked>> | 100% | 50,850 psi | 82% | 1811 fps | 100% |
| Lovex S053 | <<locked>> | 84% | 55,288 psi | 89% | 1657 fps | 100% |
| Lovex S060ᴾ | <<locked>> | 100% | 55,245 psi | 89% | 1781 fps | 99.2% |
| Lovex S062ᴾ | <<locked>> | 100% | 46,369 psi | 74% | 1749 fps | 99.3% |
| Norma 200 | <<locked>> | 90% | 55,709 psi | 89% | 1762 fps | 100% |
| Norma 201ᴾ | <<locked>> | 100% | 52,170 psi | 84% | 1791 fps | 99.7% |
| Norma 202ᴾ | <<locked>> | 100% | 52,098 psi | 84% | 1801 fps | 100% |
| Norma 203Bᴾ | <<locked>> | 100% | 46,108 psi | 74% | 1775 fps | 98.4% |
| Ramshot Big Gameᴾ | <<locked>> | 100% | 46,760 psi | 75% | 1788 fps | 98.1% |
| Ramshot TAC | <<locked>> | 98% | 54,476 psi | 87% | 1811 fps | 97.1% |
| Ramshot Wild Boarᴾ | <<locked>> | 100% | 56,043 psi | 90% | 1860 fps | 99.3% |
| Ramshot X-Terminator | <<locked>> | 96% | 55,622 psi | 89% | 1808 fps | 99.1% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 33,257 psi | 53% | 1037 fps | 100% |
| ReloadSwiss RS 36 | <<locked>> | 82% | 53,417 psi | 86% | 1696 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 94% | 53,896 psi | 86% | 1801 fps | 100% |
| ReloadSwiss RS 52ᴾ | <<locked>> | 100% | 49,588 psi | 80% | 1854 fps | 98.4% |
| ReloadSwiss RS 60ᴾ | <<locked>> | 100% | 41,365 psi | 66% | 1772 fps | 99.4% |
| Rottweil R 901 | <<locked>> | 98% | 53,388 psi | 86% | 1785 fps | 100% |
| Rottweil R 902ᴾ | <<locked>> | 100% | 49,197 psi | 79% | 1759 fps | 99.5% |
| Rottweil R 903ᴾ | <<locked>> | 100% | 39,305 psi | 63% | 1699 fps | 97.8% |
| Shooters World AR Plus | <<locked>> | 88% | 54,172 psi | 87% | 1801 fps | 100% |
| Shooters World Match Rifleᴾ | <<locked>> | 100% | 50,850 psi | 82% | 1811 fps | 100% |
| Shooters World Precisionᴾ | <<locked>> | 100% | 46,369 psi | 74% | 1749 fps | 99.3% |
| Shooters World Tactical Rifle | <<locked>> | 92% | 54,665 psi | 88% | 1781 fps | 99.6% |
| SNPE Vectan BA6 1/2 | <<locked>> | 88% | 55,680 psi | 89% | 1552 fps | 100% |
| SNPE Vectan SP 10 | <<locked>> | 90% | 53,258 psi | 85% | 1804 fps | 100% |
| SNPE Vectan SP 11ᴾ | <<locked>> | 100% | 42,322 psi | 68% | 1742 fps | 97.3% |
| SNPE Vectan SP 3 | <<locked>> | 94% | 56,391 psi | 90% | 1785 fps | 100% |
| SNPE Vectan SP 7ᴾ | <<locked>> | 100% | 55,172 psi | 88% | 1824 fps | 97.7% |
| SNPE Vectan SP 9ᴾ | <<locked>> | 100% | 51,866 psi | 83% | 1811 fps | 99% |
| SNPE Vectan Tubal 3000ᴾ | <<locked>> | 100% | 55,883 psi | 90% | 1762 fps | 100% |
| SNPE Vectan Tubal 5000ᴾ | <<locked>> | 100% | 45,049 psi | 72% | 1677 fps | 100% |
| Somchem S321 | <<locked>> | 96% | 54,636 psi | 88% | 1834 fps | 99.9% |
| Somchem S335ᴾ | <<locked>> | 100% | 53,853 psi | 86% | 1762 fps | 100% |
| Somchem S341ᴾ | <<locked>> | 100% | 54,273 psi | 87% | 1824 fps | 99.1% |
| Somchem S355ᴾ | <<locked>> | 100% | 40,959 psi | 66% | 1706 fps | 97.8% |
| Vihtavuori N120 | <<locked>> | 88% | 54,766 psi | 88% | 1690 fps | 100% |
| Vihtavuori N130 | <<locked>> | 96% | 55,680 psi | 89% | 1742 fps | 100% |
| Vihtavuori N133ᴾ | <<locked>> | 100% | 55,056 psi | 88% | 1752 fps | 100% |
| Vihtavuori N135ᴾ | <<locked>> | 100% | 47,137 psi | 76% | 1742 fps | 100% |
| Vihtavuori N140ᴾ | <<locked>> | 100% | 49,313 psi | 79% | 1755 fps | 100% |
| Vihtavuori N150ᴾ | <<locked>> | 100% | 39,407 psi | 63% | 1670 fps | 98.6% |
| Vihtavuori N530 | <<locked>> | 98% | 54,230 psi | 87% | 1804 fps | 99.8% |
| Vihtavuori N540ᴾ | <<locked>> | 100% | 47,572 psi | 76% | 1759 fps | 100% |
| Winchester 6.5 StaBALLᴾ | <<locked>> | 100% | 36,883 psi | 59% | 1624 fps | 95.9% |
| Winchester 748ᴾ | <<locked>> | 100% | 55,535 psi | 89% | 1867 fps | 100% |
| Winchester StaBALL Matchᴾ | <<locked>> | 100% | 50,879 psi | 82% | 1818 fps | 99.3% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 1680 | <<locked>> | 80% | 47,094 psi | 76% | 1644 fps | 100% |
| Accurate 2015 | <<locked>> | 80% | 31,720 psi | 51% | 1522 fps | 99.9% |
| Accurate 2200 | <<locked>> | 80% | 41,307 psi | 66% | 1667 fps | 96.4% |
| Accurate 2230 | <<locked>> | 80% | 40,683 psi | 65% | 1673 fps | 96.7% |
| Accurate 2460 | <<locked>> | 80% | 33,678 psi | 54% | 1575 fps | 98.8% |
| Accurate 2495 | <<locked>> | 80% | 24,033 psi | 39% | 1457 fps | 99% |
| Accurate 2520 | <<locked>> | 80% | 29,283 psi | 47% | 1539 fps | 97.4% |
| Accurate 4064 | <<locked>> | 80% | 22,887 psi | 37% | 1440 fps | 96.2% |
| Accurate LT-30 | <<locked>> | 80% | 40,451 psi | 65% | 1575 fps | 100% |
| Accurate LT-32 | <<locked>> | 80% | 40,843 psi | 65% | 1585 fps | 99.4% |
| ADI AR 2206H | <<locked>> | 84% | 32,866 psi | 53% | 1575 fps | 95% |
| ADI AR 2207 | <<locked>> | 80% | 43,192 psi | 69% | 1621 fps | 100% |
| ADI AR 2208 | <<locked>> | 92% | 35,940 psi | 58% | 1604 fps | 95% |
| ADI AR 2219 | <<locked>> | 80% | 37,985 psi | 61% | 1637 fps | 99.9% |
| ADI Benchmark 8208 | <<locked>> | 80% | 30,806 psi | 49% | 1522 fps | 95.7% |
| Alliant AR-Comp | <<locked>> | 80% | 28,877 psi | 46% | 1532 fps | 100% |
| Alliant Power Pro 1200-R | 45.2 gr | 80% | 34,621 psi | 56% | 1634 fps | 96.6% |
| Alliant Power Pro 2000-MR | <<locked>> | 94% | 41,075 psi | 66% | 1745 fps | 95.8% |
| Alliant Reloder- TS 15.5 | <<locked>> | 88% | 29,878 psi | 48% | 1552 fps | 95.1% |
| Alliant Reloder-10x | <<locked>> | 80% | 36,434 psi | 58% | 1588 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 90% | 34,708 psi | 56% | 1624 fps | 95.1% |
| Alliant Reloder-17 | <<locked>> | 96% | 34,069 psi | 55% | 1654 fps | 95% |
| Alliant Reloder-7 | <<locked>> | 80% | 44,135 psi | 71% | 1627 fps | 100% |
| Baschieri & Pellagri 106 | <<locked>> | 80% | 38,508 psi | 62% | 1578 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 90% | 38,508 psi | 62% | 1670 fps | 95.2% |
| Bofors RP3 | <<locked>> | 90% | 30,414 psi | 49% | 1581 fps | 95.6% |
| Hodgdon Benchmark | <<locked>> | 80% | 33,286 psi | 53% | 1529 fps | 97.1% |
| Hodgdon BL-C2 | <<locked>> | 80% | 28,094 psi | 45% | 1529 fps | 95.6% |
| Hodgdon CFE223 | 51.8 gr | 84% | 35,882 psi | 58% | 1667 fps | 95.1% |
| Hodgdon H322 | <<locked>> | 80% | 34,882 psi | 56% | 1594 fps | 99.7% |
| Hodgdon H335 | <<locked>> | 80% | 34,954 psi | 56% | 1608 fps | 99.2% |
| Hodgdon H380 | <<locked>> | 98% | 41,930 psi | 67% | 1716 fps | 95.5% |
| Hodgdon H4198 | <<locked>> | 80% | 44,614 psi | 72% | 1631 fps | 100% |
| Hodgdon H4895 | <<locked>> | 82% | 31,038 psi | 50% | 1552 fps | 95.1% |
| Hodgdon LEVERevolution | <<locked>> | 86% | 31,386 psi | 50% | 1588 fps | 95.4% |
| Hodgdon TrailBoss | <<locked>> | 80% | 24,526 psi | 39% | 899 fps | 100% |
| Hodgdon VARGET | <<locked>> | 84% | 32,213 psi | 52% | 1555 fps | 95.2% |
| IMR 3031 | <<locked>> | 80% | 27,717 psi | 44% | 1526 fps | 99% |
| IMR 4064 | <<locked>> | 90% | 35,302 psi | 57% | 1594 fps | 95.1% |
| IMR 4198 | <<locked>> | 80% | 38,029 psi | 61% | 1568 fps | 100% |
| IMR 4227 | <<locked>> | 80% | 50,343 psi | 81% | 1640 fps | 100% |
| IMR 4895 | <<locked>> | 88% | 33,170 psi | 53% | 1611 fps | 95.4% |
| IMR 8208 XBR | <<locked>> | 80% | 30,806 psi | 49% | 1522 fps | 95.7% |
| Lovex D073.4 | <<locked>> | 80% | 41,278 psi | 66% | 1670 fps | 99.5% |
| Lovex D073.5 | <<locked>> | 80% | 33,330 psi | 53% | 1572 fps | 97.7% |
| Lovex D073.6 | <<locked>> | 80% | 26,281 psi | 42% | 1496 fps | 96.3% |
| Lovex S053 | <<locked>> | 80% | 49,501 psi | 79% | 1608 fps | 100% |
| Lovex S060 | <<locked>> | 84% | 34,635 psi | 56% | 1545 fps | 95.4% |
| Lovex S062 | <<locked>> | 84% | 28,631 psi | 46% | 1506 fps | 95.1% |
| Norma 200 | <<locked>> | 80% | 40,944 psi | 66% | 1624 fps | 100% |
| Norma 201 | <<locked>> | 80% | 28,456 psi | 46% | 1486 fps | 95% |
| Norma 202 | <<locked>> | 80% | 28,108 psi | 45% | 1503 fps | 97.6% |
| Norma 203B | <<locked>> | 90% | 33,939 psi | 54% | 1617 fps | 95.5% |
| Ramshot Big Game | <<locked>> | 92% | 36,347 psi | 58% | 1657 fps | 95.6% |
| Ramshot TAC | <<locked>> | 92% | 45,063 psi | 72% | 1713 fps | 95.3% |
| Ramshot Wild Boar | <<locked>> | 84% | 33,388 psi | 54% | 1594 fps | 95% |
| Ramshot X-Terminator | <<locked>> | 82% | 35,839 psi | 57% | 1585 fps | 95.6% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 24,555 psi | 39% | 922 fps | 100% |
| ReloadSwiss RS 36 | <<locked>> | 80% | 50,270 psi | 81% | 1667 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 34,577 psi | 55% | 1581 fps | 98.3% |
| ReloadSwiss RS 52 | <<locked>> | 90% | 35,839 psi | 57% | 1680 fps | 95.2% |
| ReloadSwiss RS 60 | <<locked>> | 88% | 28,543 psi | 46% | 1558 fps | 95.3% |
| Rottweil R 901 | <<locked>> | 80% | 31,865 psi | 51% | 1526 fps | 98.3% |
| Rottweil R 902 | <<locked>> | 82% | 28,834 psi | 46% | 1490 fps | 95.1% |
| Rottweil R 903 | <<locked>> | 92% | 30,385 psi | 49% | 1575 fps | 95.2% |
| Shooters World AR Plus | <<locked>> | 80% | 41,278 psi | 66% | 1670 fps | 99.5% |
| Shooters World Match Rifle | <<locked>> | 80% | 26,281 psi | 42% | 1496 fps | 96.3% |
| Shooters World Precision | <<locked>> | 84% | 28,631 psi | 46% | 1506 fps | 95.1% |
| Shooters World Tactical Rifle | <<locked>> | 80% | 36,666 psi | 59% | 1585 fps | 97.1% |
| SNPE Vectan BA6 1/2 | <<locked>> | 80% | 45,411 psi | 73% | 1467 fps | 100% |
| SNPE Vectan SP 10 | <<locked>> | 80% | 38,363 psi | 62% | 1644 fps | 99.5% |
| SNPE Vectan SP 11 | <<locked>> | 94% | 35,244 psi | 57% | 1644 fps | 95.3% |
| SNPE Vectan SP 3 | <<locked>> | 80% | 36,999 psi | 59% | 1591 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 92% | 42,148 psi | 68% | 1690 fps | 95.3% |
| SNPE Vectan SP 9 | <<locked>> | 86% | 33,518 psi | 54% | 1588 fps | 95.1% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 30,574 psi | 49% | 1476 fps | 98.1% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 24,787 psi | 40% | 1394 fps | 97.2% |
| Somchem S321 | 48.7 gr | 80% | 32,314 psi | 52% | 1572 fps | 96.7% |
| Somchem S335 | <<locked>> | 80% | 29,704 psi | 48% | 1480 fps | 98.6% |
| Somchem S341 | <<locked>> | 86% | 34,330 psi | 55% | 1591 fps | 95.2% |
| Somchem S355 | <<locked>> | 92% | 32,140 psi | 52% | 1585 fps | 95.5% |
| Vihtavuori N120 | <<locked>> | 80% | 43,279 psi | 69% | 1588 fps | 100% |
| Vihtavuori N130 | <<locked>> | 80% | 34,838 psi | 56% | 1532 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 30,342 psi | 49% | 1483 fps | 99.7% |
| Vihtavuori N135 | <<locked>> | 80% | 25,440 psi | 41% | 1463 fps | 99.2% |
| Vihtavuori N140 | <<locked>> | 80% | 26,672 psi | 43% | 1463 fps | 97.4% |
| Vihtavuori N150 | <<locked>> | 88% | 27,296 psi | 44% | 1486 fps | 95% |
| Vihtavuori N530 | <<locked>> | 80% | 30,400 psi | 49% | 1519 fps | 95.7% |
| Vihtavuori N540 | <<locked>> | 80% | 25,527 psi | 41% | 1457 fps | 96.3% |
| Winchester 6.5 StaBALL | <<locked>> | 98% | 34,693 psi | 56% | 1591 fps | 95.1% |
| Winchester 748 | <<locked>> | 80% | 29,138 psi | 47% | 1539 fps | 96.1% |
| Winchester StaBALL Match | <<locked>> | 86% | 32,561 psi | 52% | 1588 fps | 95.5% |
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 92 powders for .458 Win.Mag. loaded with the .458 | 600gr | Barnes RNSP. Hodgdon CFE223 delivers the highest muzzle velocity at 1,883 fps; across all powders the maximum-charge window runs from 1,010 fps to 1,883 fps. Accurate 2495 gives the best case fill at 100 %, and 92 of the 92 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (430 MPa), the top charges use 53–90 %, leaving at least 10 % headroom. The 600.0 gr projectile in 0.458" calls for a 1:6.0 twist; slower twists will usually not stabilise this weight. Accurate 2495, Accurate 4064, ADI AR 2206H 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 CFE223, Alliant Power Pro 1200-R, Somchem S321 rank at the top here: for .458 Win.Mag. with the .458 | 600gr | Barnes RNSP they combine a high case fill with complete burn and sit in the upper velocity band. Hodgdon TrailBoss, ReloadSwiss RS 14 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.