Load Specifications
Load data in caliber .300 Rem. Ultra Mag. with .308 | 159gr | IBEX TRD 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 Accurate MAGPRO.
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% | 55,056 psi | 85% | 2930 fps | 100% |
| Accurate 4350 | <<locked>> | 82% | 55,535 psi | 85% | 2966 fps | 100% |
| Accurate MAGPRO | <<locked>> | 90% | 56,869 psi | 88% | 3068 fps | 98% |
| ADI AR 2209 | <<locked>> | 88% | 55,419 psi | 85% | 3002 fps | 99.3% |
| ADI AR 2213 | <<locked>> | 92% | 57,261 psi | 88% | 3064 fps | 98.9% |
| ADI AR 2217ᴾ | <<locked>> | 100% | 55,680 psi | 86% | 3025 fps | 99% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 50,560 psi | 78% | 2992 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 88% | 55,738 psi | 86% | 3002 fps | 99.3% |
| Alliant Reloder-16 | <<locked>> | 84% | 55,405 psi | 85% | 3009 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 90% | 58,784 psi | 90% | 3048 fps | 99.6% |
| Alliant Reloder-22 | <<locked>> | 92% | 57,870 psi | 89% | 3068 fps | 99.6% |
| Alliant Reloder-23 | <<locked>> | 92% | 55,695 psi | 86% | 2989 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 96% | 55,245 psi | 85% | 3045 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 88% | 56,478 psi | 87% | 3074 fps | 100% |
| Baschieri & Pellagri 109 | <<locked>> | 94% | 58,508 psi | 90% | 3012 fps | 96.8% |
| Bofors RP15 | <<locked>> | 94% | 57,101 psi | 88% | 3051 fps | 99.5% |
| Bofors RP30 | <<locked>> | 98% | 55,390 psi | 85% | 3045 fps | 99.1% |
| Bofors RP5 | <<locked>> | 92% | 57,870 psi | 89% | 3068 fps | 99.6% |
| Bofors RP7 | <<locked>> | 82% | 56,608 psi | 87% | 2953 fps | 99.8% |
| Hodgdon H1000 | <<locked>> | 98% | 57,203 psi | 88% | 3048 fps | 99.5% |
| Hodgdon H414 | <<locked>> | 82% | 56,289 psi | 87% | 3005 fps | 99.9% |
| Hodgdon H4350 | <<locked>> | 82% | 58,233 psi | 90% | 3012 fps | 99.6% |
| Hodgdon H4831 | <<locked>> | 90% | 57,072 psi | 88% | 3002 fps | 98.3% |
| Hodgdon H4831 SC | <<locked>> | 90% | 55,840 psi | 86% | 2982 fps | 98.1% |
| Hodgdon Hybrid 100V | <<locked>> | 86% | 56,057 psi | 86% | 2933 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 98% | 57,754 psi | 89% | 3173 fps | 100% |
| Hodgdon Superformance | <<locked>> | 82% | 56,753 psi | 87% | 3031 fps | 99.9% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,536 psi | 58% | 1952 fps | 100% |
| IMR 4350 | <<locked>> | 86% | 58,291 psi | 90% | 2986 fps | 99.9% |
| IMR 4451 Enduron | <<locked>> | 82% | 57,566 psi | 89% | 2969 fps | 99.9% |
| IMR 4831 | <<locked>> | 84% | 55,448 psi | 85% | 2949 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 90% | 57,479 psi | 88% | 2979 fps | 98.5% |
| IMR 7828 SSC | <<locked>> | 92% | 55,303 psi | 85% | 3041 fps | 98.7% |
| IMR 8133 Enduronᴾ | <<locked>> | 100% | 46,311 psi | 71% | 2904 fps | 97.3% |
| Lovex S065 | <<locked>> | 82% | 55,477 psi | 85% | 2923 fps | 100% |
| Lovex S070 | <<locked>> | 84% | 57,377 psi | 88% | 2972 fps | 100% |
| Lovex S071 | <<locked>> | 96% | 56,405 psi | 87% | 2949 fps | 100% |
| Norma 204 | <<locked>> | 84% | 55,869 psi | 86% | 2986 fps | 99.2% |
| Norma 217ᴾ | <<locked>> | 100% | 46,789 psi | 72% | 2936 fps | 99.2% |
| Norma MRP | <<locked>> | 90% | 57,899 psi | 89% | 3084 fps | 100% |
| Norma URP | <<locked>> | 84% | 56,869 psi | 88% | 2992 fps | 100% |
| Ramshot Grand | <<locked>> | 92% | 56,231 psi | 87% | 3061 fps | 99.1% |
| Ramshot Hunter | <<locked>> | 84% | 55,753 psi | 86% | 2992 fps | 100% |
| Ramshot Magnum | <<locked>> | 94% | 55,158 psi | 85% | 2995 fps | 99.8% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 38,450 psi | 59% | 1998 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 82% | 55,230 psi | 85% | 2976 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 84% | 56,927 psi | 88% | 3051 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 96% | 55,042 psi | 85% | 3104 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 98% | 54,650 psi | 84% | 3058 fps | 98% |
| Rottweil R 904 | <<locked>> | 88% | 56,463 psi | 87% | 2972 fps | 98.7% |
| Rottweil R 905 | <<locked>> | 90% | 58,697 psi | 90% | 3041 fps | 99.7% |
| Rottweil R 907 | <<locked>> | 82% | 56,608 psi | 87% | 2953 fps | 99.8% |
| Shooters World Long Rifle | <<locked>> | 82% | 55,477 psi | 85% | 2923 fps | 100% |
| Shooters World SW4350 | <<locked>> | 84% | 57,377 psi | 88% | 2972 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 84% | 58,044 psi | 89% | 2923 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 90% | 58,262 psi | 90% | 3038 fps | 99.6% |
| Somchem S361 | <<locked>> | 88% | 58,392 psi | 90% | 2959 fps | 98.5% |
| Somchem S365 | <<locked>> | 86% | 58,001 psi | 89% | 2995 fps | 100% |
| Somchem S385 | <<locked>> | 88% | 55,695 psi | 86% | 2959 fps | 99.7% |
| Vihtavuori N160 | <<locked>> | 84% | 58,276 psi | 90% | 2979 fps | 100% |
| Vihtavuori N165 | <<locked>> | 92% | 55,347 psi | 85% | 2936 fps | 99.6% |
| Vihtavuori N550 | <<locked>> | 84% | 57,783 psi | 89% | 2982 fps | 100% |
| Vihtavuori N555 | <<locked>> | 90% | 58,262 psi | 90% | 3022 fps | 100% |
| Vihtavuori N560 | <<locked>> | 90% | 57,305 psi | 88% | 3077 fps | 98.6% |
| Vihtavuori N565 | <<locked>> | 96% | 58,450 psi | 90% | 3068 fps | 98.9% |
| Vihtavuori N568 | <<locked>> | 98% | 55,332 psi | 85% | 3058 fps | 97.5% |
| Winchester 6.5 StaBALL | <<locked>> | 84% | 57,986 psi | 89% | 2927 fps | 100% |
| Winchester 760 | <<locked>> | 82% | 56,289 psi | 87% | 3005 fps | 99.9% |
| Winchester StaBALL HD | <<locked>> | 94% | 58,494 psi | 90% | 3127 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 90% | 55,288 psi | 85% | 2949 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 3100 | <<locked>> | 80% | 39,943 psi | 61% | 2667 fps | 98.5% |
| Accurate 4350 | <<locked>> | 80% | 51,924 psi | 80% | 2910 fps | 100% |
| Accurate MAGPRO | 82.8 gr | 84% | 46,195 psi | 71% | 2881 fps | 95.5% |
| ADI AR 2209 | <<locked>> | 80% | 42,728 psi | 66% | 2776 fps | 96.9% |
| ADI AR 2213 | <<locked>> | 84% | 43,961 psi | 68% | 2825 fps | 96% |
| ADI AR 2217 | <<locked>> | 90% | 40,205 psi | 62% | 2730 fps | 95% |
| ADI AR 2225 | <<locked>> | 86% | 32,532 psi | 50% | 2582 fps | 95.1% |
| Alliant Power Pro Varmint | <<locked>> | 80% | 43,221 psi | 67% | 2779 fps | 97% |
| Alliant Reloder-16 | <<locked>> | 80% | 48,704 psi | 75% | 2907 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 42,873 psi | 66% | 2772 fps | 97% |
| Alliant Reloder-22 | <<locked>> | 80% | 39,059 psi | 60% | 2720 fps | 95.9% |
| Alliant Reloder-23 | <<locked>> | 80% | 37,782 psi | 58% | 2687 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 33,069 psi | 51% | 2602 fps | 97.2% |
| Alliant Reloder-26 | <<locked>> | 80% | 42,105 psi | 65% | 2835 fps | 99.8% |
| Baschieri & Pellagri 109 | <<locked>> | 90% | 51,648 psi | 79% | 2897 fps | 95.1% |
| Bofors RP15 | <<locked>> | 82% | 39,044 psi | 60% | 2717 fps | 95.7% |
| Bofors RP30 | <<locked>> | 88% | 39,798 psi | 61% | 2756 fps | 95.4% |
| Bofors RP5 | <<locked>> | 80% | 39,059 psi | 60% | 2720 fps | 95.9% |
| Bofors RP7 | <<locked>> | 80% | 53,287 psi | 82% | 2904 fps | 99.5% |
| Hodgdon H1000 | <<locked>> | 86% | 38,464 psi | 59% | 2694 fps | 95% |
| Hodgdon H414 | <<locked>> | 80% | 52,779 psi | 81% | 2949 fps | 99.7% |
| Hodgdon H4350 | <<locked>> | 80% | 54,650 psi | 84% | 2956 fps | 99.3% |
| Hodgdon H4831 | <<locked>> | 82% | 43,787 psi | 67% | 2769 fps | 95.2% |
| Hodgdon H4831 SC | <<locked>> | 82% | 43,018 psi | 66% | 2753 fps | 95% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 46,369 psi | 71% | 2789 fps | 100% |
| Hodgdon Retumbo | 78.4 gr | 84% | 36,767 psi | 57% | 2740 fps | 95.6% |
| Hodgdon Superformance | <<locked>> | 80% | 52,968 psi | 82% | 2972 fps | 99.7% |
| Hodgdon TrailBoss | <<locked>> | 80% | 28,166 psi | 43% | 1755 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 48,385 psi | 74% | 2828 fps | 98.9% |
| IMR 4451 Enduron | <<locked>> | 80% | 54,041 psi | 83% | 2917 fps | 99.7% |
| IMR 4831 | <<locked>> | 80% | 48,863 psi | 75% | 2848 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 82% | 45,121 psi | 69% | 2766 fps | 95.8% |
| IMR 7828 SSC | <<locked>> | 84% | 42,511 psi | 65% | 2805 fps | 95.6% |
| IMR 8133 Enduron | <<locked>> | 96% | 40,640 psi | 63% | 2789 fps | 95.5% |
| Lovex S065 | <<locked>> | 80% | 52,257 psi | 80% | 2874 fps | 100% |
| Lovex S070 | <<locked>> | 80% | 50,749 psi | 78% | 2867 fps | 99.6% |
| Lovex S071 | <<locked>> | 80% | 34,766 psi | 54% | 2552 fps | 97% |
| Norma 204 | <<locked>> | 80% | 48,849 psi | 75% | 2871 fps | 98.2% |
| Norma 217 | <<locked>> | 90% | 33,808 psi | 52% | 2644 fps | 95.1% |
| Norma MRP | <<locked>> | 80% | 41,046 psi | 63% | 2792 fps | 97.9% |
| Norma URP | <<locked>> | 80% | 50,053 psi | 77% | 2887 fps | 100% |
| Ramshot Grand | <<locked>> | 84% | 42,438 psi | 65% | 2812 fps | 96% |
| Ramshot Hunter | <<locked>> | 80% | 48,907 psi | 75% | 2881 fps | 99.7% |
| Ramshot Magnum | <<locked>> | 82% | 36,027 psi | 55% | 2638 fps | 95.8% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,906 psi | 44% | 1798 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 51,721 psi | 80% | 2923 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 49,545 psi | 76% | 2940 fps | 100% |
| ReloadSwiss RS 76 | 81.9 gr | 82% | 33,924 psi | 52% | 2654 fps | 95.7% |
| ReloadSwiss RS 80 | <<locked>> | 92% | 43,903 psi | 68% | 2861 fps | 95.1% |
| Rottweil R 904 | <<locked>> | 80% | 44,034 psi | 68% | 2753 fps | 96.1% |
| Rottweil R 905 | <<locked>> | 80% | 42,583 psi | 66% | 2766 fps | 97% |
| Rottweil R 907 | <<locked>> | 80% | 53,287 psi | 82% | 2904 fps | 99.5% |
| Shooters World Long Rifle | <<locked>> | 80% | 52,257 psi | 80% | 2874 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 50,749 psi | 78% | 2867 fps | 99.6% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 51,271 psi | 79% | 2822 fps | 99.6% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 42,235 psi | 65% | 2759 fps | 96.9% |
| Somchem S361 | <<locked>> | 80% | 45,150 psi | 69% | 2736 fps | 95.6% |
| Somchem S365 | <<locked>> | 80% | 47,529 psi | 73% | 2848 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 43,294 psi | 67% | 2746 fps | 98% |
| Vihtavuori N160 | <<locked>> | 80% | 51,387 psi | 79% | 2877 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 37,695 psi | 58% | 2618 fps | 96% |
| Vihtavuori N550 | <<locked>> | 80% | 50,952 psi | 78% | 2881 fps | 100% |
| Vihtavuori N555 | <<locked>> | 80% | 42,569 psi | 66% | 2769 fps | 99.9% |
| Vihtavuori N560 | <<locked>> | 82% | 43,903 psi | 68% | 2838 fps | 95.5% |
| Vihtavuori N565 | <<locked>> | 86% | 42,163 psi | 65% | 2779 fps | 95.3% |
| Vihtavuori N568 | <<locked>> | 94% | 48,153 psi | 74% | 2936 fps | 95.8% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 50,691 psi | 78% | 2828 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 52,779 psi | 81% | 2949 fps | 99.7% |
| Winchester StaBALL HD | <<locked>> | 80% | 34,432 psi | 53% | 2726 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 39,653 psi | 61% | 2664 fps | 96% |
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 70 powders for .300 Rem. Ultra Mag. loaded with the .308 | 159gr | IBEX TRD. Hodgdon Retumbo delivers the highest muzzle velocity at 3,173 fps; across all powders the maximum-charge window runs from 1,952 fps to 3,173 fps. ADI AR 2217 gives the best case fill at 100 %, and 70 of the 70 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 159.0 gr projectile in 0.308" calls for a 1:11.5 twist; slower twists will usually not stabilise this weight. ADI AR 2217, ADI AR 2225, Hodgdon TrailBoss 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, Accurate MAGPRO rank at the top here: for .300 Rem. Ultra Mag. with the .308 | 159gr | IBEX TRD they combine a high case fill with complete burn and sit in the upper velocity band. Always begin at the start load and work up in small increments while checking case and primer for pressure signs.