Load Specifications
Load data in caliber .300 Rem. Ultra Mag. with .308 | 165gr | Woodleigh PP SN 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, Winchester StaBALL HD and ReloadSwiss RS 76.
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>> | 90% | 55,042 psi | 85% | 2900 fps | 100% |
| Accurate 4350 | <<locked>> | 82% | 55,506 psi | 85% | 2933 fps | 100% |
| Accurate MAGPRO | <<locked>> | 90% | 57,841 psi | 89% | 3051 fps | 98.7% |
| ADI AR 2209 | <<locked>> | 88% | 56,478 psi | 87% | 2989 fps | 99.7% |
| ADI AR 2213 | <<locked>> | 92% | 58,595 psi | 90% | 3054 fps | 99.4% |
| ADI AR 2217ᴾ | <<locked>> | 100% | 57,101 psi | 88% | 3018 fps | 99.6% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 51,459 psi | 79% | 2976 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 84% | 56,463 psi | 87% | 2989 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 88% | 56,101 psi | 86% | 2979 fps | 99.7% |
| Alliant Reloder-22 | <<locked>> | 90% | 55,129 psi | 85% | 2992 fps | 99.6% |
| Alliant Reloder-23 | <<locked>> | 92% | 56,565 psi | 87% | 2959 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 96% | 56,579 psi | 87% | 3022 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 88% | 57,566 psi | 89% | 3048 fps | 100% |
| Alliant Reloder-33ᴾ | <<locked>> | 100% | 54,781 psi | 84% | 3028 fps | 96.6% |
| Baschieri & Pellagri 109 | <<locked>> | 92% | 55,883 psi | 86% | 2949 fps | 97% |
| Bofors RP15 | <<locked>> | 94% | 58,030 psi | 89% | 3035 fps | 99.8% |
| Bofors RP30 | <<locked>> | 98% | 56,550 psi | 87% | 3028 fps | 99.5% |
| Bofors RP5 | <<locked>> | 90% | 55,129 psi | 85% | 2992 fps | 99.6% |
| Bofors RP7 | <<locked>> | 82% | 56,884 psi | 88% | 2933 fps | 99.9% |
| Hodgdon H1000 | <<locked>> | 98% | 58,711 psi | 90% | 3041 fps | 99.9% |
| Hodgdon H414 | <<locked>> | 82% | 56,826 psi | 87% | 2982 fps | 100% |
| Hodgdon H4831 | <<locked>> | 90% | 57,972 psi | 89% | 2989 fps | 98.9% |
| Hodgdon H4831 SC | <<locked>> | 90% | 56,942 psi | 88% | 2972 fps | 98.8% |
| Hodgdon Hybrid 100V | <<locked>> | 86% | 56,652 psi | 87% | 2907 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 96% | 55,376 psi | 85% | 3100 fps | 100% |
| Hodgdon Superformance | <<locked>> | 82% | 58,001 psi | 89% | 3018 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,333 psi | 57% | 1936 fps | 100% |
| IMR 4350 | <<locked>> | 84% | 55,492 psi | 85% | 2920 fps | 99.9% |
| IMR 4451 Enduron | <<locked>> | 82% | 58,160 psi | 90% | 2953 fps | 100% |
| IMR 4831 | <<locked>> | 84% | 55,854 psi | 86% | 2923 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 90% | 58,407 psi | 90% | 2969 fps | 99% |
| IMR 7828 SSC | <<locked>> | 92% | 56,637 psi | 87% | 3031 fps | 99.2% |
| IMR 8133 Enduronᴾ | <<locked>> | 100% | 46,949 psi | 72% | 2884 fps | 98% |
| Lovex S065 | <<locked>> | 82% | 55,579 psi | 86% | 2900 fps | 100% |
| Lovex S070 | <<locked>> | 84% | 57,566 psi | 89% | 2949 fps | 100% |
| Lovex S071 | <<locked>> | 96% | 56,579 psi | 87% | 2923 fps | 100% |
| Norma 204 | <<locked>> | 84% | 56,710 psi | 87% | 2972 fps | 99.6% |
| Norma 217ᴾ | <<locked>> | 100% | 47,514 psi | 73% | 2907 fps | 99.6% |
| Norma MRP | <<locked>> | 88% | 55,100 psi | 85% | 3009 fps | 100% |
| Norma URP | <<locked>> | 84% | 57,363 psi | 88% | 2966 fps | 100% |
| Ramshot Grand | <<locked>> | 92% | 58,030 psi | 89% | 3054 fps | 99.6% |
| Ramshot Hunter | <<locked>> | 84% | 56,536 psi | 87% | 2972 fps | 100% |
| Ramshot Magnum | <<locked>> | 94% | 56,724 psi | 87% | 2986 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 38,159 psi | 59% | 1982 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 82% | 55,767 psi | 86% | 2953 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 84% | 58,276 psi | 90% | 3031 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 96% | 56,681 psi | 87% | 3091 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 98% | 56,173 psi | 86% | 3045 fps | 98.7% |
| Rottweil R 904 | <<locked>> | 88% | 57,290 psi | 88% | 2959 fps | 99.2% |
| Rottweil R 905 | <<locked>> | 88% | 55,637 psi | 86% | 2966 fps | 99.7% |
| Rottweil R 907 | <<locked>> | 82% | 56,884 psi | 88% | 2933 fps | 99.9% |
| Shooters World Long Rifle | <<locked>> | 82% | 55,579 psi | 86% | 2900 fps | 100% |
| Shooters World SW4350 | <<locked>> | 84% | 57,566 psi | 89% | 2949 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 84% | 58,421 psi | 90% | 2904 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 88% | 55,216 psi | 85% | 2963 fps | 99.6% |
| Somchem S361 | <<locked>> | 86% | 55,288 psi | 85% | 2890 fps | 98.5% |
| Somchem S365 | <<locked>> | 86% | 58,668 psi | 90% | 2966 fps | 100% |
| Somchem S385 | <<locked>> | 88% | 56,188 psi | 86% | 2940 fps | 99.9% |
| Vihtavuori N160 | <<locked>> | 82% | 55,347 psi | 85% | 2907 fps | 100% |
| Vihtavuori N165 | <<locked>> | 92% | 56,115 psi | 86% | 2920 fps | 99.9% |
| Vihtavuori N550 | <<locked>> | 84% | 58,436 psi | 90% | 2959 fps | 100% |
| Vihtavuori N555 | <<locked>> | 90% | 58,581 psi | 90% | 2989 fps | 100% |
| Vihtavuori N560 | <<locked>> | 90% | 58,610 psi | 90% | 3064 fps | 99.1% |
| Vihtavuori N565 | <<locked>> | 94% | 55,390 psi | 85% | 2989 fps | 98.9% |
| Vihtavuori N568 | <<locked>> | 98% | 56,681 psi | 87% | 3048 fps | 98.3% |
| Vihtavuori N570ᴾ | <<locked>> | 100% | 57,769 psi | 89% | 3104 fps | 96.9% |
| Winchester 6.5 StaBALL | <<locked>> | 82% | 54,926 psi | 85% | 2851 fps | 100% |
| Winchester 760 | <<locked>> | 82% | 57,029 psi | 88% | 2986 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 92% | 55,999 psi | 86% | 3045 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 90% | 56,144 psi | 86% | 2933 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% | 38,986 psi | 60% | 2621 fps | 98.7% |
| Accurate 4350 | <<locked>> | 80% | 51,706 psi | 80% | 2877 fps | 100% |
| Accurate MAGPRO | <<locked>> | 82% | 43,366 psi | 67% | 2795 fps | 95.2% |
| ADI AR 2209 | <<locked>> | 80% | 42,960 psi | 66% | 2756 fps | 97.5% |
| ADI AR 2213 | <<locked>> | 82% | 41,191 psi | 63% | 2743 fps | 95.7% |
| ADI AR 2217 | <<locked>> | 90% | 40,263 psi | 62% | 2710 fps | 95.9% |
| ADI AR 2225 | <<locked>> | 86% | 31,937 psi | 49% | 2549 fps | 95.6% |
| Alliant Reloder-16 | <<locked>> | 80% | 49,327 psi | 76% | 2884 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 42,975 psi | 66% | 2746 fps | 97.5% |
| Alliant Reloder-22 | <<locked>> | 80% | 38,986 psi | 60% | 2690 fps | 96.4% |
| Alliant Reloder-23 | <<locked>> | 80% | 37,550 psi | 58% | 2648 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 32,518 psi | 50% | 2562 fps | 97.5% |
| Alliant Reloder-26 | <<locked>> | 80% | 42,192 psi | 65% | 2799 fps | 99.9% |
| Alliant Reloder-33 | <<locked>> | 98% | 50,633 psi | 78% | 2959 fps | 95.6% |
| Baschieri & Pellagri 109 | <<locked>> | 88% | 49,197 psi | 76% | 2831 fps | 95.2% |
| Bofors RP15 | <<locked>> | 80% | 36,230 psi | 56% | 2625 fps | 95.2% |
| Bofors RP30 | <<locked>> | 88% | 39,900 psi | 61% | 2726 fps | 96% |
| Bofors RP5 | <<locked>> | 80% | 38,986 psi | 60% | 2690 fps | 96.4% |
| Bofors RP7 | <<locked>> | 80% | 53,345 psi | 82% | 2877 fps | 99.7% |
| Hodgdon H1000 | <<locked>> | 86% | 38,377 psi | 59% | 2671 fps | 95.8% |
| Hodgdon H414 | <<locked>> | 80% | 53,098 psi | 82% | 2927 fps | 99.9% |
| Hodgdon H4831 | <<locked>> | 80% | 41,031 psi | 63% | 2687 fps | 95% |
| Hodgdon H4831 SC | <<locked>> | 82% | 43,149 psi | 66% | 2730 fps | 95.7% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 46,470 psi | 72% | 2759 fps | 100% |
| Hodgdon Retumbo | 80 gr | 82% | 34,026 psi | 52% | 2641 fps | 95% |
| Hodgdon Superformance | <<locked>> | 80% | 53,867 psi | 83% | 2956 fps | 99.9% |
| Hodgdon TrailBoss | <<locked>> | 80% | 28,021 psi | 43% | 1742 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 48,704 psi | 75% | 2808 fps | 99.3% |
| IMR 4451 Enduron | <<locked>> | 80% | 54,665 psi | 84% | 2900 fps | 99.9% |
| IMR 4831 | <<locked>> | 80% | 48,834 psi | 75% | 2818 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 42,366 psi | 65% | 2687 fps | 95.7% |
| IMR 7828 SSC | <<locked>> | 82% | 39,798 psi | 61% | 2720 fps | 95.3% |
| IMR 8133 Enduron | <<locked>> | 94% | 38,029 psi | 59% | 2697 fps | 95.1% |
| Lovex S065 | <<locked>> | 80% | 52,170 psi | 80% | 2848 fps | 100% |
| Lovex S070 | <<locked>> | 80% | 50,749 psi | 78% | 2841 fps | 99.8% |
| Lovex S071 | <<locked>> | 80% | 33,504 psi | 52% | 2497 fps | 97.1% |
| Norma 204 | <<locked>> | 80% | 49,240 psi | 76% | 2851 fps | 98.7% |
| Norma 217 | <<locked>> | 90% | 33,301 psi | 51% | 2602 fps | 95.6% |
| Norma MRP | <<locked>> | 80% | 41,191 psi | 63% | 2762 fps | 98.4% |
| Norma URP | <<locked>> | 80% | 50,314 psi | 77% | 2861 fps | 100% |
| Ramshot Grand | <<locked>> | 82% | 39,653 psi | 61% | 2726 fps | 95.7% |
| Ramshot Hunter | <<locked>> | 80% | 49,211 psi | 76% | 2858 fps | 99.9% |
| Ramshot Magnum | <<locked>> | 80% | 33,040 psi | 51% | 2539 fps | 95.1% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,674 psi | 44% | 1781 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 51,851 psi | 80% | 2894 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 50,299 psi | 77% | 2917 fps | 100% |
| ReloadSwiss RS 76 | 85.6 gr | 82% | 33,344 psi | 51% | 2615 fps | 96.2% |
| ReloadSwiss RS 80 | <<locked>> | 92% | 44,396 psi | 68% | 2838 fps | 96% |
| Rottweil R 904 | <<locked>> | 80% | 44,019 psi | 68% | 2733 fps | 96.7% |
| Rottweil R 905 | <<locked>> | 80% | 42,395 psi | 65% | 2736 fps | 97.5% |
| Rottweil R 907 | <<locked>> | 80% | 53,345 psi | 82% | 2877 fps | 99.7% |
| Shooters World Long Rifle | <<locked>> | 80% | 52,170 psi | 80% | 2848 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 50,749 psi | 78% | 2841 fps | 99.8% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 51,227 psi | 79% | 2799 fps | 99.8% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 42,047 psi | 65% | 2730 fps | 97.4% |
| Somchem S361 | <<locked>> | 80% | 45,107 psi | 69% | 2717 fps | 96.3% |
| Somchem S365 | <<locked>> | 80% | 47,732 psi | 73% | 2815 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 43,047 psi | 66% | 2717 fps | 98.4% |
| Vihtavuori N160 | <<locked>> | 80% | 51,706 psi | 80% | 2851 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 37,333 psi | 57% | 2585 fps | 96.5% |
| Vihtavuori N550 | <<locked>> | 80% | 51,140 psi | 79% | 2854 fps | 100% |
| Vihtavuori N555 | <<locked>> | 80% | 41,989 psi | 65% | 2726 fps | 100% |
| Vihtavuori N560 | <<locked>> | 80% | 41,075 psi | 63% | 2749 fps | 95.2% |
| Vihtavuori N565 | <<locked>> | 86% | 41,901 psi | 64% | 2743 fps | 95.8% |
| Vihtavuori N568 | <<locked>> | 92% | 45,440 psi | 70% | 2851 fps | 95.6% |
| Vihtavuori N570 | <<locked>> | 98% | 53,635 psi | 83% | 3038 fps | 95.9% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 51,169 psi | 79% | 2802 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 53,287 psi | 82% | 2927 fps | 99.9% |
| Winchester StaBALL HD | 80.1 gr | 80% | 34,621 psi | 53% | 2680 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 39,494 psi | 61% | 2638 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 | 165gr | Woodleigh PP SN. Vihtavuori N570 delivers the highest muzzle velocity at 3,104 fps; across all powders the maximum-charge window runs from 1,936 fps to 3,104 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 57–90 %, leaving at least 10 % headroom. The 165.0 gr projectile in 0.308" calls for a 1:15.5 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, Winchester StaBALL HD, ReloadSwiss RS 76 rank at the top here: for .300 Rem. Ultra Mag. with the .308 | 165gr | Woodleigh PP SN 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.