Load Specifications
Load data in caliber .300 Rem. SA Ultra Mag. with .308 | 150gr | Barnes MRX BT bullet and 97 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Alliant Power Pro 2000-MR, ReloadSwiss RS 52 and Hodgdon LEVERevolution.
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.
A valid access license is required to use the Personalized Load Calculator.
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 2015 | <<locked>> | 90% | 57,827 psi | 89% | 2920 fps | 100% |
| Accurate 2200 | <<locked>> | 82% | 58,030 psi | 89% | 3028 fps | 99.3% |
| Accurate 2460 | <<locked>> | 86% | 56,405 psi | 87% | 2946 fps | 100% |
| Accurate 2495 | <<locked>> | 94% | 55,143 psi | 85% | 2933 fps | 100% |
| Accurate 2520 | <<locked>> | 90% | 58,378 psi | 90% | 3012 fps | 100% |
| Accurate 4064 | <<locked>> | 98% | 58,581 psi | 90% | 3025 fps | 100% |
| Accurate 4350ᴾ | <<locked>> | 100% | 47,471 psi | 73% | 2927 fps | 97.6% |
| Accurate LT-30 | <<locked>> | 84% | 57,450 psi | 88% | 2867 fps | 100% |
| Accurate LT-32 | <<locked>> | 84% | 57,870 psi | 89% | 2894 fps | 100% |
| ADI AR 2206H | <<locked>> | 92% | 57,000 psi | 88% | 3015 fps | 99.7% |
| ADI AR 2208 | <<locked>> | 98% | 58,204 psi | 90% | 3012 fps | 99.4% |
| ADI AR 2219 | <<locked>> | 84% | 58,726 psi | 90% | 2995 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 90% | 56,217 psi | 86% | 2969 fps | 99.9% |
| Alliant AR-Comp | <<locked>> | 90% | 56,347 psi | 87% | 2953 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 86% | 58,146 psi | 89% | 3087 fps | 99.9% |
| Alliant Power Pro 2000-MR | <<locked>> | 94% | 56,768 psi | 87% | 3133 fps | 99.4% |
| Alliant Reloder- TS 15.5 | <<locked>> | 98% | 57,334 psi | 88% | 3031 fps | 99.9% |
| Alliant Reloder-10x | <<locked>> | 86% | 57,696 psi | 89% | 2930 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 96% | 58,378 psi | 90% | 3058 fps | 99.5% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 46,992 psi | 72% | 2933 fps | 97.7% |
| Alliant Reloder-17ᴾ | <<locked>> | 100% | 54,824 psi | 84% | 3100 fps | 99.8% |
| Baschieri & Pellagri 106 | <<locked>> | 84% | 56,971 psi | 88% | 2864 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 92% | 57,276 psi | 88% | 3035 fps | 99.1% |
| Bofors RP3 | <<locked>> | 98% | 58,015 psi | 89% | 3048 fps | 100% |
| Hodgdon Benchmark | <<locked>> | 90% | 58,363 psi | 90% | 2956 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 90% | 55,288 psi | 85% | 2999 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 88% | 57,653 psi | 89% | 3107 fps | 99.5% |
| Hodgdon H322 | <<locked>> | 86% | 57,101 psi | 88% | 2972 fps | 100% |
| Hodgdon H335 | <<locked>> | 86% | 58,610 psi | 90% | 3005 fps | 100% |
| Hodgdon H380 | <<locked>> | 96% | 55,767 psi | 86% | 3002 fps | 98.5% |
| Hodgdon H4895 | <<locked>> | 92% | 57,508 psi | 88% | 3028 fps | 99.9% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 43,004 psi | 66% | 2808 fps | 98.2% |
| Hodgdon LEVERevolution | <<locked>> | 94% | 56,724 psi | 87% | 3061 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 34,650 psi | 53% | 1804 fps | 100% |
| Hodgdon VARGET | <<locked>> | 92% | 55,477 psi | 85% | 2979 fps | 99.7% |
| IMR 3031 | <<locked>> | 92% | 57,043 psi | 88% | 3015 fps | 100% |
| IMR 4064 | <<locked>> | 96% | 57,508 psi | 88% | 2995 fps | 99.5% |
| IMR 4166 Enduron | <<locked>> | 94% | 58,494 psi | 90% | 2976 fps | 96.8% |
| IMR 4198 | <<locked>> | 86% | 58,001 psi | 89% | 2887 fps | 100% |
| IMR 4451 Enduronᴾ | <<locked>> | 100% | 57,537 psi | 89% | 2992 fps | 96.6% |
| IMR 4831ᴾ | <<locked>> | 100% | 45,295 psi | 70% | 2867 fps | 97.2% |
| IMR 4895 | <<locked>> | 94% | 56,086 psi | 86% | 3035 fps | 99.6% |
| IMR 8208 XBR | <<locked>> | 90% | 56,217 psi | 86% | 2969 fps | 99.9% |
| Lovex D073.5 | <<locked>> | 86% | 56,536 psi | 87% | 2959 fps | 100% |
| Lovex D073.6 | <<locked>> | 92% | 56,376 psi | 87% | 2995 fps | 100% |
| Lovex S060 | <<locked>> | 92% | 57,014 psi | 88% | 2943 fps | 99.6% |
| Lovex S062 | <<locked>> | 96% | 56,724 psi | 87% | 2989 fps | 100% |
| Lovex S065ᴾ | <<locked>> | 100% | 52,591 psi | 81% | 2923 fps | 97.2% |
| Norma 200 | <<locked>> | 82% | 57,174 psi | 88% | 2897 fps | 100% |
| Norma 201 | <<locked>> | 92% | 55,405 psi | 85% | 2959 fps | 99.9% |
| Norma 202 | <<locked>> | 92% | 56,014 psi | 86% | 2966 fps | 100% |
| Norma 203B | <<locked>> | 96% | 57,464 psi | 88% | 3045 fps | 99.7% |
| Norma URPᴾ | <<locked>> | 100% | 47,282 psi | 73% | 2917 fps | 97.5% |
| Ramshot Big Game | <<locked>> | 96% | 58,407 psi | 90% | 3071 fps | 99.7% |
| Ramshot TAC | <<locked>> | 90% | 57,058 psi | 88% | 2986 fps | 98.1% |
| Ramshot Wild Boar | <<locked>> | 90% | 56,275 psi | 87% | 3009 fps | 99.6% |
| Ramshot X-Terminator | <<locked>> | 88% | 57,870 psi | 89% | 2976 fps | 99.6% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 34,969 psi | 54% | 1844 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 86% | 56,144 psi | 86% | 2959 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 96% | 56,594 psi | 87% | 2986 fps | 97.2% |
| ReloadSwiss RS 52 | <<locked>> | 94% | 58,784 psi | 90% | 3127 fps | 99.6% |
| ReloadSwiss RS 60ᴾ | <<locked>> | 100% | 58,624 psi | 90% | 3166 fps | 100% |
| ReloadSwiss RS 62ᴾ | <<locked>> | 100% | 47,268 psi | 73% | 2943 fps | 97.3% |
| ReloadSwiss RS 70ᴾ | <<locked>> | 100% | 48,254 psi | 74% | 2966 fps | 96.7% |
| Rottweil R 901 | <<locked>> | 90% | 56,376 psi | 87% | 2946 fps | 100% |
| Rottweil R 902 | <<locked>> | 94% | 55,854 psi | 86% | 2956 fps | 99.9% |
| Rottweil R 903ᴾ | <<locked>> | 100% | 57,522 psi | 88% | 3031 fps | 99.9% |
| Shooters World Long Rifleᴾ | <<locked>> | 100% | 52,591 psi | 81% | 2923 fps | 97.2% |
| Shooters World Match Rifle | <<locked>> | 92% | 56,376 psi | 87% | 2995 fps | 100% |
| Shooters World Precision | <<locked>> | 96% | 56,724 psi | 87% | 2989 fps | 100% |
| Shooters World Tactical Rifle | <<locked>> | 84% | 55,840 psi | 86% | 2927 fps | 99.9% |
| SNPE Vectan BA6 1/2 | <<locked>> | 82% | 57,435 psi | 88% | 2608 fps | 100% |
| SNPE Vectan SP 10 | <<locked>> | 82% | 55,100 psi | 85% | 2953 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 98% | 56,275 psi | 87% | 3048 fps | 99.6% |
| SNPE Vectan SP 3 | <<locked>> | 84% | 55,419 psi | 85% | 2907 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 90% | 54,940 psi | 85% | 2959 fps | 98.2% |
| SNPE Vectan SP 9 | <<locked>> | 92% | 55,564 psi | 85% | 2989 fps | 99.5% |
| SNPE Vectan Tubal 3000 | <<locked>> | 92% | 58,015 psi | 89% | 2910 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 98% | 57,609 psi | 89% | 2900 fps | 100% |
| SNPE Vectan Tubal 7000ᴾ | <<locked>> | 100% | 53,214 psi | 82% | 2874 fps | 95.8% |
| Somchem S321 | <<locked>> | 88% | 57,769 psi | 89% | 3009 fps | 100% |
| Somchem S335 | <<locked>> | 92% | 56,652 psi | 87% | 2900 fps | 100% |
| Somchem S341 | <<locked>> | 92% | 58,566 psi | 90% | 3012 fps | 99.7% |
| Somchem S355ᴾ | <<locked>> | 100% | 58,189 psi | 90% | 3035 fps | 99.9% |
| Somchem S365ᴾ | <<locked>> | 100% | 41,959 psi | 65% | 2861 fps | 99.2% |
| Vihtavuori N130 | <<locked>> | 88% | 57,493 psi | 88% | 2874 fps | 100% |
| Vihtavuori N133 | <<locked>> | 92% | 57,943 psi | 89% | 2894 fps | 100% |
| Vihtavuori N135 | <<locked>> | 96% | 58,798 psi | 90% | 2972 fps | 100% |
| Vihtavuori N140 | <<locked>> | 94% | 56,753 psi | 87% | 2946 fps | 100% |
| Vihtavuori N150ᴾ | <<locked>> | 100% | 56,318 psi | 87% | 2963 fps | 100% |
| Vihtavuori N160ᴾ | <<locked>> | 100% | 50,053 psi | 77% | 2923 fps | 97.9% |
| Vihtavuori N530 | <<locked>> | 90% | 56,985 psi | 88% | 2972 fps | 100% |
| Vihtavuori N540 | <<locked>> | 96% | 58,479 psi | 90% | 2989 fps | 100% |
| Vihtavuori N550ᴾ | <<locked>> | 100% | 49,081 psi | 76% | 2927 fps | 97.6% |
| Winchester 6.5 StaBALLᴾ | <<locked>> | 100% | 51,256 psi | 79% | 2910 fps | 99.5% |
| Winchester 748 | <<locked>> | 90% | 56,362 psi | 87% | 3018 fps | 100% |
| Winchester StaBALL Match | <<locked>> | 92% | 55,332 psi | 85% | 2995 fps | 99.8% |
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 2015 | <<locked>> | 80% | 42,032 psi | 65% | 2677 fps | 100% |
| Accurate 2200 | <<locked>> | 80% | 54,230 psi | 83% | 2969 fps | 98.9% |
| Accurate 2460 | <<locked>> | 80% | 45,992 psi | 71% | 2785 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 34,287 psi | 53% | 2575 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 41,176 psi | 63% | 2733 fps | 99.5% |
| Accurate 4064 | <<locked>> | 80% | 32,460 psi | 50% | 2556 fps | 98.7% |
| Accurate 4350 | <<locked>> | 94% | 38,116 psi | 59% | 2740 fps | 95.1% |
| Accurate LT-30 | <<locked>> | 80% | 50,995 psi | 78% | 2776 fps | 100% |
| Accurate LT-32 | <<locked>> | 80% | 51,401 psi | 79% | 2799 fps | 100% |
| ADI AR 2206H | <<locked>> | 80% | 38,769 psi | 60% | 2680 fps | 96.7% |
| ADI AR 2208 | <<locked>> | 84% | 37,492 psi | 58% | 2635 fps | 95.4% |
| ADI AR 2219 | <<locked>> | 80% | 51,358 psi | 79% | 2890 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 80% | 40,872 psi | 63% | 2703 fps | 98.4% |
| Alliant AR-Comp | <<locked>> | 80% | 40,161 psi | 62% | 2707 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 80% | 47,456 psi | 73% | 2910 fps | 99% |
| Alliant Power Pro 2000-MR | 53 gr | 84% | 40,147 psi | 62% | 2812 fps | 95.9% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 31,966 psi | 49% | 2539 fps | 95.4% |
| Alliant Reloder-10x | <<locked>> | 80% | 47,747 psi | 73% | 2785 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 82% | 37,057 psi | 57% | 2664 fps | 95.5% |
| Alliant Reloder-16 | <<locked>> | 94% | 39,088 psi | 60% | 2762 fps | 95.3% |
| Alliant Reloder-17 | <<locked>> | 86% | 33,982 psi | 52% | 2664 fps | 95.2% |
| Baschieri & Pellagri 106 | <<locked>> | 80% | 49,937 psi | 77% | 2766 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 37,811 psi | 58% | 2674 fps | 95.1% |
| Bofors RP3 | <<locked>> | 80% | 31,169 psi | 48% | 2533 fps | 95.2% |
| Hodgdon Benchmark | <<locked>> | 80% | 42,931 psi | 66% | 2703 fps | 99.1% |
| Hodgdon BL-C2 | <<locked>> | 80% | 39,059 psi | 60% | 2710 fps | 98.5% |
| Hodgdon CFE223 | <<locked>> | 80% | 43,105 psi | 66% | 2854 fps | 97.3% |
| Hodgdon H322 | <<locked>> | 80% | 46,920 psi | 72% | 2818 fps | 100% |
| Hodgdon H335 | <<locked>> | 80% | 47,718 psi | 73% | 2841 fps | 100% |
| Hodgdon H380 | <<locked>> | 88% | 42,627 psi | 66% | 2772 fps | 95.8% |
| Hodgdon H4895 | <<locked>> | 80% | 39,059 psi | 60% | 2697 fps | 97.3% |
| Hodgdon Hybrid 100V | <<locked>> | 92% | 33,199 psi | 51% | 2585 fps | 95.1% |
| Hodgdon LEVERevolution | 49.5 gr | 80% | 34,969 psi | 54% | 2651 fps | 96.6% |
| Hodgdon TrailBoss | <<locked>> | 80% | 25,657 psi | 39% | 1611 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 37,811 psi | 58% | 2651 fps | 96.9% |
| IMR 3031 | <<locked>> | 80% | 38,101 psi | 59% | 2703 fps | 100% |
| IMR 4064 | <<locked>> | 82% | 36,956 psi | 57% | 2615 fps | 95.6% |
| IMR 4166 Enduron | <<locked>> | 90% | 51,474 psi | 79% | 2864 fps | 95.4% |
| IMR 4198 | <<locked>> | 80% | 48,515 psi | 75% | 2756 fps | 100% |
| IMR 4451 Enduron | <<locked>> | 96% | 50,618 psi | 78% | 2881 fps | 95.1% |
| IMR 4831 | <<locked>> | 96% | 39,479 psi | 61% | 2749 fps | 95.6% |
| IMR 4895 | <<locked>> | 80% | 35,433 psi | 55% | 2638 fps | 95.7% |
| IMR 8208 XBR | <<locked>> | 80% | 40,872 psi | 63% | 2703 fps | 98.4% |
| Lovex D073.5 | <<locked>> | 80% | 45,847 psi | 71% | 2792 fps | 99.6% |
| Lovex D073.6 | <<locked>> | 80% | 37,231 psi | 57% | 2661 fps | 98.9% |
| Lovex S060 | <<locked>> | 80% | 39,450 psi | 61% | 2631 fps | 96.9% |
| Lovex S062 | <<locked>> | 80% | 34,156 psi | 53% | 2562 fps | 96.7% |
| Lovex S065 | <<locked>> | 94% | 43,526 psi | 67% | 2759 fps | 95% |
| Norma 200 | <<locked>> | 80% | 53,838 psi | 83% | 2851 fps | 100% |
| Norma 201 | <<locked>> | 80% | 37,898 psi | 58% | 2638 fps | 97.8% |
| Norma 202 | <<locked>> | 80% | 38,014 psi | 58% | 2654 fps | 99.4% |
| Norma 203B | <<locked>> | 80% | 33,997 psi | 52% | 2592 fps | 95.1% |
| Norma URP | <<locked>> | 94% | 38,827 psi | 60% | 2746 fps | 95.1% |
| Ramshot Big Game | <<locked>> | 82% | 36,042 psi | 55% | 2661 fps | 95.5% |
| Ramshot TAC | <<locked>> | 82% | 43,714 psi | 67% | 2753 fps | 95.3% |
| Ramshot Wild Boar | <<locked>> | 80% | 40,074 psi | 62% | 2717 fps | 97% |
| Ramshot X-Terminator | <<locked>> | 80% | 44,353 psi | 68% | 2753 fps | 97.9% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 25,817 psi | 40% | 1647 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 45,905 psi | 71% | 2795 fps | 99.8% |
| ReloadSwiss RS 50 | <<locked>> | 92% | 49,501 psi | 76% | 2871 fps | 95.7% |
| ReloadSwiss RS 52 | 49 gr | 80% | 35,926 psi | 55% | 2700 fps | 95% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 29,501 psi | 45% | 2543 fps | 95.8% |
| ReloadSwiss RS 62 | <<locked>> | 96% | 41,002 psi | 63% | 2822 fps | 95.6% |
| ReloadSwiss RS 70 | <<locked>> | 98% | 45,165 psi | 69% | 2904 fps | 95.8% |
| Rottweil R 901 | <<locked>> | 80% | 41,394 psi | 64% | 2694 fps | 99.7% |
| Rottweil R 902 | <<locked>> | 80% | 35,940 psi | 55% | 2585 fps | 97.2% |
| Rottweil R 903 | <<locked>> | 84% | 33,547 psi | 52% | 2585 fps | 95.8% |
| Shooters World Long Rifle | <<locked>> | 94% | 43,526 psi | 67% | 2759 fps | 95% |
| Shooters World Match Rifle | <<locked>> | 80% | 37,231 psi | 57% | 2661 fps | 98.9% |
| Shooters World Precision | <<locked>> | 80% | 34,156 psi | 53% | 2562 fps | 96.7% |
| Shooters World Tactical Rifle | <<locked>> | 80% | 48,718 psi | 75% | 2815 fps | 99.3% |
| SNPE Vectan BA6 1/2 | <<locked>> | 80% | 54,404 psi | 84% | 2569 fps | 100% |
| SNPE Vectan SP 10 | <<locked>> | 80% | 51,721 psi | 80% | 2900 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 84% | 35,114 psi | 54% | 2644 fps | 95.3% |
| SNPE Vectan SP 3 | <<locked>> | 80% | 48,646 psi | 75% | 2805 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 82% | 41,423 psi | 64% | 2717 fps | 95.3% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 37,492 psi | 58% | 2651 fps | 96.2% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 39,581 psi | 61% | 2608 fps | 99.6% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 32,474 psi | 50% | 2464 fps | 99.1% |
| SNPE Vectan Tubal 7000 | <<locked>> | 98% | 49,632 psi | 76% | 2818 fps | 95% |
| Somchem S321 | <<locked>> | 80% | 43,874 psi | 67% | 2782 fps | 99.1% |
| Somchem S335 | <<locked>> | 80% | 39,117 psi | 60% | 2612 fps | 99.9% |
| Somchem S341 | <<locked>> | 80% | 38,493 psi | 59% | 2664 fps | 96.5% |
| Somchem S355 | <<locked>> | 82% | 32,503 psi | 50% | 2543 fps | 95.1% |
| Somchem S365 | <<locked>> | 90% | 30,153 psi | 46% | 2566 fps | 95.4% |
| Vihtavuori N130 | <<locked>> | 80% | 44,962 psi | 69% | 2690 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 39,798 psi | 61% | 2615 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 34,969 psi | 54% | 2582 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 36,027 psi | 55% | 2589 fps | 99.4% |
| Vihtavuori N150 | <<locked>> | 80% | 28,935 psi | 45% | 2428 fps | 95.2% |
| Vihtavuori N160 | <<locked>> | 94% | 40,872 psi | 63% | 2753 fps | 95.7% |
| Vihtavuori N530 | <<locked>> | 80% | 40,727 psi | 63% | 2694 fps | 98.4% |
| Vihtavuori N540 | <<locked>> | 80% | 34,519 psi | 53% | 2569 fps | 98.7% |
| Vihtavuori N550 | <<locked>> | 94% | 39,987 psi | 62% | 2753 fps | 95.2% |
| Winchester 6.5 StaBALL | <<locked>> | 88% | 34,040 psi | 52% | 2566 fps | 95.5% |
| Winchester 748 | <<locked>> | 80% | 39,856 psi | 61% | 2736 fps | 98.9% |
| Winchester StaBALL Match | <<locked>> | 80% | 36,593 psi | 56% | 2651 fps | 96.7% |
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 97 powders for .300 Rem. SA Ultra Mag. loaded with the .308 | 150gr | Barnes MRX BT. ReloadSwiss RS 60 delivers the highest muzzle velocity at 3,166 fps; across all powders the maximum-charge window runs from 1,804 fps to 3,166 fps. Accurate 4350 gives the best case fill at 100 %, and 97 of the 97 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (448 MPa), the top charges use 53–90 %, leaving at least 10 % headroom. The 150.0 gr projectile in 0.308" calls for a 1:11.5 twist; slower twists will usually not stabilise this weight. Accurate 4350, Alliant Reloder-16, Alliant Reloder-17 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 Power Pro 2000-MR, ReloadSwiss RS 52, Hodgdon LEVERevolution rank at the top here: for .300 Rem. SA Ultra Mag. with the .308 | 150gr | Barnes MRX BT 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.