Load Specifications
Load data in caliber .300 Rem. Ultra Mag. with .308 | 168gr | Sierra MatchKing bullet and 70 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Hodgdon Retumbo, ReloadSwiss RS 76 and Winchester StaBALL HD.
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: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 3100 | <<locked>> | 92% | 58,581 psi | 90% | 2930 fps | 100% |
| Accurate 4350 | <<locked>> | 82% | 55,013 psi | 85% | 2907 fps | 100% |
| Accurate MAGPRO | <<locked>> | 90% | 57,493 psi | 88% | 3028 fps | 98.7% |
| ADI AR 2209 | <<locked>> | 88% | 56,130 psi | 86% | 2966 fps | 99.7% |
| ADI AR 2213 | <<locked>> | 92% | 58,175 psi | 90% | 3028 fps | 99.4% |
| ADI AR 2217ᴾ | <<locked>> | 100% | 56,594 psi | 87% | 2992 fps | 99.5% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 51,039 psi | 79% | 2953 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 84% | 56,173 psi | 86% | 2963 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 88% | 55,796 psi | 86% | 2956 fps | 99.7% |
| Alliant Reloder-22 | <<locked>> | 92% | 58,450 psi | 90% | 3022 fps | 99.9% |
| Alliant Reloder-23 | <<locked>> | 92% | 56,289 psi | 87% | 2936 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 96% | 56,173 psi | 86% | 2999 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 88% | 57,101 psi | 88% | 3022 fps | 100% |
| Alliant Reloder-33ᴾ | <<locked>> | 100% | 54,244 psi | 83% | 3005 fps | 96.6% |
| Baschieri & Pellagri 109 | <<locked>> | 92% | 55,637 psi | 86% | 2927 fps | 97% |
| Bofors RP15 | <<locked>> | 94% | 57,595 psi | 89% | 3009 fps | 99.8% |
| Bofors RP30 | <<locked>> | 98% | 56,028 psi | 86% | 3005 fps | 99.5% |
| Bofors RP5 | <<locked>> | 92% | 58,450 psi | 90% | 3022 fps | 99.9% |
| Bofors RP7 | <<locked>> | 82% | 56,594 psi | 87% | 2907 fps | 99.9% |
| Hodgdon H1000 | <<locked>> | 98% | 58,262 psi | 90% | 3018 fps | 99.9% |
| Hodgdon H414 | <<locked>> | 82% | 56,623 psi | 87% | 2959 fps | 100% |
| Hodgdon H4831 | <<locked>> | 90% | 57,740 psi | 89% | 2966 fps | 98.9% |
| Hodgdon H4831 SC | <<locked>> | 90% | 56,507 psi | 87% | 2946 fps | 98.8% |
| Hodgdon Hybrid 100V | <<locked>> | 86% | 56,405 psi | 87% | 2884 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 96% | 55,013 psi | 85% | 3074 fps | 100% |
| Hodgdon Superformance | <<locked>> | 82% | 57,725 psi | 89% | 2992 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,376 psi | 58% | 1916 fps | 100% |
| IMR 4350 | <<locked>> | 86% | 58,711 psi | 90% | 2946 fps | 100% |
| IMR 4451 Enduron | <<locked>> | 82% | 57,899 psi | 89% | 2927 fps | 100% |
| IMR 4831 | <<locked>> | 84% | 55,419 psi | 85% | 2897 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 90% | 58,160 psi | 90% | 2946 fps | 99.1% |
| IMR 7828 SSC | <<locked>> | 92% | 56,376 psi | 87% | 3009 fps | 99.3% |
| IMR 8133 Enduronᴾ | <<locked>> | 100% | 46,456 psi | 71% | 2858 fps | 98% |
| Lovex S065 | <<locked>> | 82% | 55,288 psi | 85% | 2874 fps | 100% |
| Lovex S070 | <<locked>> | 84% | 57,363 psi | 88% | 2927 fps | 100% |
| Lovex S071 | <<locked>> | 96% | 56,130 psi | 86% | 2897 fps | 100% |
| Norma 204 | <<locked>> | 84% | 56,362 psi | 87% | 2946 fps | 99.6% |
| Norma 217ᴾ | <<locked>> | 100% | 47,166 psi | 73% | 2887 fps | 99.6% |
| Norma MRP | <<locked>> | 90% | 58,682 psi | 90% | 3045 fps | 100% |
| Norma URP | <<locked>> | 84% | 57,101 psi | 88% | 2943 fps | 100% |
| Ramshot Grand | <<locked>> | 92% | 57,363 psi | 88% | 3028 fps | 99.6% |
| Ramshot Hunter | <<locked>> | 84% | 56,217 psi | 87% | 2946 fps | 100% |
| Ramshot Magnum | <<locked>> | 94% | 56,217 psi | 87% | 2959 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 38,218 psi | 59% | 1962 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 82% | 55,390 psi | 85% | 2927 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 84% | 57,943 psi | 89% | 3009 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 96% | 56,260 psi | 87% | 3068 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 98% | 55,608 psi | 86% | 3018 fps | 98.7% |
| Rottweil R 904 | <<locked>> | 88% | 56,956 psi | 88% | 2936 fps | 99.2% |
| Rottweil R 905 | <<locked>> | 88% | 55,288 psi | 85% | 2943 fps | 99.7% |
| Rottweil R 907 | <<locked>> | 82% | 56,594 psi | 87% | 2907 fps | 99.9% |
| Shooters World Long Rifle | <<locked>> | 82% | 55,288 psi | 85% | 2874 fps | 100% |
| Shooters World SW4350 | <<locked>> | 84% | 57,363 psi | 88% | 2927 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 84% | 58,073 psi | 89% | 2877 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 90% | 58,697 psi | 90% | 2995 fps | 99.9% |
| Somchem S361 | <<locked>> | 88% | 58,697 psi | 90% | 2920 fps | 99% |
| Somchem S365 | <<locked>> | 86% | 58,276 psi | 90% | 2943 fps | 100% |
| Somchem S385 | <<locked>> | 88% | 55,912 psi | 86% | 2913 fps | 99.9% |
| Vihtavuori N160 | <<locked>> | 82% | 54,897 psi | 84% | 2881 fps | 100% |
| Vihtavuori N165 | <<locked>> | 92% | 55,709 psi | 86% | 2894 fps | 99.9% |
| Vihtavuori N550 | <<locked>> | 84% | 58,044 psi | 89% | 2936 fps | 100% |
| Vihtavuori N555 | <<locked>> | 90% | 58,247 psi | 90% | 2966 fps | 100% |
| Vihtavuori N560 | <<locked>> | 90% | 58,189 psi | 90% | 3041 fps | 99.2% |
| Vihtavuori N565 | <<locked>> | 94% | 54,853 psi | 84% | 2963 fps | 98.9% |
| Vihtavuori N568 | <<locked>> | 98% | 56,260 psi | 87% | 3025 fps | 98.3% |
| Vihtavuori N570ᴾ | <<locked>> | 100% | 57,334 psi | 88% | 3081 fps | 96.9% |
| Winchester 6.5 StaBALL | <<locked>> | 84% | 58,682 psi | 90% | 2881 fps | 100% |
| Winchester 760 | <<locked>> | 82% | 56,811 psi | 87% | 2963 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 92% | 55,506 psi | 85% | 3018 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 90% | 55,753 psi | 86% | 2907 fps | 99.7% |
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 3100 | <<locked>> | 80% | 38,696 psi | 60% | 2602 fps | 98.7% |
| Accurate 4350 | <<locked>> | 80% | 51,358 psi | 79% | 2851 fps | 100% |
| Accurate MAGPRO | <<locked>> | 82% | 43,047 psi | 66% | 2772 fps | 95.3% |
| ADI AR 2209 | <<locked>> | 80% | 42,656 psi | 66% | 2730 fps | 97.5% |
| ADI AR 2213 | <<locked>> | 82% | 41,002 psi | 63% | 2720 fps | 95.8% |
| ADI AR 2217 | <<locked>> | 90% | 39,900 psi | 61% | 2687 fps | 95.9% |
| ADI AR 2225 | <<locked>> | 86% | 31,691 psi | 49% | 2526 fps | 95.6% |
| Alliant Reloder-16 | <<locked>> | 80% | 48,950 psi | 75% | 2858 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 42,685 psi | 66% | 2723 fps | 97.6% |
| Alliant Reloder-22 | <<locked>> | 80% | 38,740 psi | 60% | 2671 fps | 96.5% |
| Alliant Reloder-23 | <<locked>> | 80% | 37,405 psi | 58% | 2628 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 32,285 psi | 50% | 2539 fps | 97.6% |
| Alliant Reloder-26 | <<locked>> | 80% | 41,974 psi | 65% | 2779 fps | 99.9% |
| Alliant Reloder-33 | <<locked>> | 98% | 50,154 psi | 77% | 2936 fps | 95.5% |
| Baschieri & Pellagri 109 | <<locked>> | 88% | 48,907 psi | 75% | 2808 fps | 95.2% |
| Bofors RP15 | <<locked>> | 80% | 35,969 psi | 55% | 2602 fps | 95.2% |
| Bofors RP30 | <<locked>> | 86% | 36,912 psi | 57% | 2644 fps | 95% |
| Bofors RP5 | <<locked>> | 80% | 38,740 psi | 60% | 2671 fps | 96.5% |
| Bofors RP7 | <<locked>> | 80% | 53,026 psi | 82% | 2851 fps | 99.7% |
| Hodgdon H1000 | <<locked>> | 86% | 38,101 psi | 59% | 2648 fps | 95.9% |
| Hodgdon H414 | <<locked>> | 80% | 52,852 psi | 81% | 2904 fps | 99.9% |
| Hodgdon H4831 | <<locked>> | 80% | 40,814 psi | 63% | 2667 fps | 95% |
| Hodgdon H4831 SC | <<locked>> | 82% | 42,917 psi | 66% | 2710 fps | 95.7% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 46,137 psi | 71% | 2736 fps | 100% |
| Hodgdon Retumbo | 78.7 gr | 82% | 33,808 psi | 52% | 2621 fps | 95.1% |
| Hodgdon Superformance | <<locked>> | 80% | 53,388 psi | 82% | 2930 fps | 99.9% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,920 psi | 43% | 1719 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 48,414 psi | 75% | 2785 fps | 99.3% |
| IMR 4451 Enduron | <<locked>> | 80% | 54,346 psi | 84% | 2874 fps | 99.9% |
| IMR 4831 | <<locked>> | 80% | 48,559 psi | 75% | 2792 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 42,148 psi | 65% | 2667 fps | 95.7% |
| IMR 7828 SSC | <<locked>> | 82% | 39,566 psi | 61% | 2700 fps | 95.4% |
| IMR 8133 Enduron | <<locked>> | 94% | 37,666 psi | 58% | 2677 fps | 95.2% |
| Lovex S065 | <<locked>> | 80% | 52,025 psi | 80% | 2825 fps | 100% |
| Lovex S070 | <<locked>> | 80% | 50,415 psi | 78% | 2818 fps | 99.8% |
| Lovex S071 | <<locked>> | 80% | 33,330 psi | 51% | 2480 fps | 97.1% |
| Norma 204 | <<locked>> | 80% | 48,979 psi | 75% | 2828 fps | 98.7% |
| Norma 217 | <<locked>> | 90% | 33,040 psi | 51% | 2582 fps | 95.6% |
| Norma MRP | <<locked>> | 80% | 40,959 psi | 63% | 2743 fps | 98.4% |
| Norma URP | <<locked>> | 80% | 50,009 psi | 77% | 2838 fps | 100% |
| Ramshot Grand | <<locked>> | 82% | 39,450 psi | 61% | 2707 fps | 95.8% |
| Ramshot Hunter | <<locked>> | 80% | 48,965 psi | 75% | 2835 fps | 99.9% |
| Ramshot Magnum | <<locked>> | 80% | 32,851 psi | 51% | 2520 fps | 95.2% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,587 psi | 44% | 1762 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 51,648 psi | 79% | 2871 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 49,922 psi | 77% | 2894 fps | 100% |
| ReloadSwiss RS 76 | 84.2 gr | 82% | 33,127 psi | 51% | 2595 fps | 96.2% |
| ReloadSwiss RS 80 | <<locked>> | 92% | 43,932 psi | 68% | 2815 fps | 96% |
| Rottweil R 904 | <<locked>> | 80% | 43,874 psi | 68% | 2710 fps | 96.8% |
| Rottweil R 905 | <<locked>> | 80% | 42,250 psi | 65% | 2713 fps | 97.6% |
| Rottweil R 907 | <<locked>> | 80% | 53,026 psi | 82% | 2851 fps | 99.7% |
| Shooters World Long Rifle | <<locked>> | 80% | 52,025 psi | 80% | 2825 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 50,415 psi | 78% | 2818 fps | 99.8% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 50,952 psi | 78% | 2772 fps | 99.8% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 41,901 psi | 64% | 2707 fps | 97.5% |
| Somchem S361 | <<locked>> | 80% | 44,817 psi | 69% | 2694 fps | 96.4% |
| Somchem S365 | <<locked>> | 80% | 47,398 psi | 73% | 2792 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 42,801 psi | 66% | 2694 fps | 98.4% |
| Vihtavuori N160 | <<locked>> | 80% | 51,387 psi | 79% | 2828 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 37,101 psi | 57% | 2562 fps | 96.5% |
| Vihtavuori N550 | <<locked>> | 80% | 50,879 psi | 78% | 2831 fps | 100% |
| Vihtavuori N555 | <<locked>> | 80% | 41,669 psi | 64% | 2707 fps | 100% |
| Vihtavuori N560 | <<locked>> | 80% | 40,872 psi | 63% | 2726 fps | 95.2% |
| Vihtavuori N565 | <<locked>> | 86% | 41,582 psi | 64% | 2723 fps | 95.8% |
| Vihtavuori N568 | <<locked>> | 92% | 45,121 psi | 69% | 2831 fps | 95.6% |
| Vihtavuori N570 | <<locked>> | 98% | 53,200 psi | 82% | 3012 fps | 95.9% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 50,865 psi | 78% | 2779 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 53,040 psi | 82% | 2904 fps | 99.9% |
| Winchester StaBALL HD | 78.8 gr | 80% | 34,301 psi | 53% | 2661 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 39,247 psi | 60% | 2618 fps | 96.6% |
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 76 powders for .300 Rem. Ultra Mag. loaded with the .308 | 168gr | Sierra MatchKing. Vihtavuori N570 delivers the highest muzzle velocity at 3,081 fps; across all powders the maximum-charge window runs from 1,916 fps to 3,081 fps. ADI AR 2217 gives the best case fill at 100 %, and 76 of the 76 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (448 MPa), the top charges use 58–90 %, leaving at least 10 % headroom. The 168.0 gr projectile in 0.308" calls for a 1:13.5 twist; slower twists will usually not stabilise this weight. ADI AR 2217, ADI AR 2218, ADI AR 2225 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 Retumbo, ReloadSwiss RS 76, Winchester StaBALL HD rank at the top here: for .300 Rem. Ultra Mag. with the .308 | 168gr | Sierra MatchKing they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, ADI AR 2218, Alliant Reloder-50, IMR 7977 Enduron 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.