Load Specifications
Load data in caliber .300 RCM with .308 | 150gr | Fox Classic Hunter bullet and 96 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 ReloadSwiss RS 60.
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 2015 | <<locked>> | 88% | 54,592 psi | 86% | 2877 fps | 100% |
| Accurate 2460 | <<locked>> | 86% | 56,536 psi | 89% | 2949 fps | 100% |
| Accurate 2495 | <<locked>> | 94% | 55,274 psi | 87% | 2933 fps | 100% |
| Accurate 2520 | <<locked>> | 88% | 54,694 psi | 86% | 2963 fps | 100% |
| Accurate 4064 | <<locked>> | 96% | 55,201 psi | 87% | 2979 fps | 100% |
| Accurate 4350ᴾ | <<locked>> | 100% | 47,572 psi | 75% | 2927 fps | 97.6% |
| Accurate LT-30 | <<locked>> | 84% | 57,580 psi | 90% | 2867 fps | 100% |
| Accurate LT-32 | <<locked>> | 82% | 54,708 psi | 86% | 2851 fps | 100% |
| ADI AR 2206H | <<locked>> | 92% | 57,116 psi | 90% | 3018 fps | 99.7% |
| ADI AR 2208 | <<locked>> | 96% | 54,665 psi | 86% | 2959 fps | 99.1% |
| ADI AR 2219 | <<locked>> | 82% | 55,100 psi | 86% | 2946 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 90% | 56,347 psi | 88% | 2972 fps | 100% |
| Alliant AR-Comp | <<locked>> | 90% | 56,521 psi | 89% | 2956 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 84% | 54,563 psi | 86% | 3031 fps | 99.7% |
| Alliant Power Pro 2000-MR | <<locked>> | 94% | 57,188 psi | 90% | 3143 fps | 99.4% |
| Alliant Reloder- TS 15.5 | <<locked>> | 96% | 54,099 psi | 85% | 2982 fps | 99.8% |
| Alliant Reloder-10x | <<locked>> | 84% | 54,215 psi | 85% | 2884 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 94% | 54,824 psi | 86% | 3002 fps | 99.2% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 47,079 psi | 74% | 2936 fps | 97.7% |
| Alliant Reloder-17ᴾ | <<locked>> | 100% | 54,911 psi | 86% | 3100 fps | 99.8% |
| Baschieri & Pellagri 106 | <<locked>> | 84% | 57,087 psi | 89% | 2867 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 92% | 57,334 psi | 90% | 3038 fps | 99.2% |
| Bofors RP3 | <<locked>> | 96% | 54,317 psi | 85% | 2995 fps | 99.8% |
| Hodgdon Benchmark | <<locked>> | 88% | 55,259 psi | 87% | 2913 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 90% | 55,390 psi | 87% | 3002 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 86% | 53,722 psi | 84% | 3045 fps | 99.1% |
| Hodgdon H322 | <<locked>> | 86% | 57,261 psi | 90% | 2976 fps | 100% |
| Hodgdon H335 | <<locked>> | 84% | 54,781 psi | 86% | 2953 fps | 100% |
| Hodgdon H380 | <<locked>> | 96% | 56,159 psi | 88% | 3012 fps | 98.5% |
| Hodgdon H4895 | <<locked>> | 92% | 57,653 psi | 90% | 3031 fps | 99.9% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 43,323 psi | 68% | 2818 fps | 98.3% |
| Hodgdon LEVERevolution | <<locked>> | 94% | 56,797 psi | 89% | 3064 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 34,476 psi | 54% | 1801 fps | 100% |
| Hodgdon VARGET | <<locked>> | 92% | 55,912 psi | 88% | 2986 fps | 99.8% |
| IMR 3031 | <<locked>> | 92% | 57,203 psi | 90% | 3018 fps | 100% |
| IMR 4064 | <<locked>> | 96% | 57,609 psi | 90% | 2999 fps | 99.5% |
| IMR 4166 Enduron | <<locked>> | 92% | 54,984 psi | 86% | 2923 fps | 96.2% |
| IMR 4198 | <<locked>> | 84% | 54,810 psi | 86% | 2848 fps | 100% |
| IMR 4451 Enduronᴾ | <<locked>> | 100% | 57,580 psi | 90% | 2995 fps | 96.6% |
| IMR 4831ᴾ | <<locked>> | 100% | 45,426 psi | 71% | 2867 fps | 97.3% |
| IMR 4895 | <<locked>> | 94% | 56,246 psi | 88% | 3038 fps | 99.7% |
| IMR 8208 XBR | <<locked>> | 90% | 56,347 psi | 88% | 2972 fps | 100% |
| Lovex D073.5 | <<locked>> | 86% | 56,652 psi | 89% | 2963 fps | 100% |
| Lovex D073.6 | <<locked>> | 92% | 56,492 psi | 89% | 2995 fps | 100% |
| Lovex S060 | <<locked>> | 92% | 57,130 psi | 90% | 2946 fps | 99.7% |
| Lovex S062 | <<locked>> | 96% | 57,159 psi | 90% | 2995 fps | 100% |
| Lovex S065ᴾ | <<locked>> | 100% | 52,721 psi | 83% | 2927 fps | 97.2% |
| Norma 200 | <<locked>> | 82% | 57,392 psi | 90% | 2900 fps | 100% |
| Norma 201 | <<locked>> | 92% | 55,521 psi | 87% | 2963 fps | 99.9% |
| Norma 202 | <<locked>> | 92% | 56,144 psi | 88% | 2969 fps | 100% |
| Norma 203B | <<locked>> | 96% | 57,551 psi | 90% | 3045 fps | 99.7% |
| Norma URPᴾ | <<locked>> | 100% | 47,340 psi | 74% | 2920 fps | 97.5% |
| Ramshot Big Game | <<locked>> | 94% | 54,752 psi | 86% | 3018 fps | 99.4% |
| Ramshot TAC | <<locked>> | 90% | 57,116 psi | 90% | 2989 fps | 98.1% |
| Ramshot Wild Boar | <<locked>> | 90% | 56,362 psi | 88% | 3012 fps | 99.6% |
| Ramshot X-Terminator | <<locked>> | 86% | 54,230 psi | 85% | 2923 fps | 99.3% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 34,780 psi | 55% | 1844 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 86% | 56,289 psi | 88% | 2963 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 96% | 56,710 psi | 89% | 2989 fps | 97.2% |
| ReloadSwiss RS 52 | <<locked>> | 92% | 55,013 psi | 86% | 3071 fps | 99.2% |
| ReloadSwiss RS 60 | <<locked>> | 98% | 54,940 psi | 86% | 3110 fps | 100% |
| ReloadSwiss RS 62ᴾ | <<locked>> | 100% | 47,326 psi | 74% | 2946 fps | 97.3% |
| ReloadSwiss RS 70ᴾ | <<locked>> | 100% | 48,559 psi | 76% | 2972 fps | 96.8% |
| Rottweil R 901 | <<locked>> | 90% | 56,536 psi | 89% | 2949 fps | 100% |
| Rottweil R 902 | <<locked>> | 94% | 56,028 psi | 88% | 2956 fps | 99.9% |
| Rottweil R 903ᴾ | <<locked>> | 100% | 57,667 psi | 90% | 3035 fps | 99.9% |
| Shooters World Long Rifleᴾ | <<locked>> | 100% | 52,721 psi | 83% | 2927 fps | 97.2% |
| Shooters World Match Rifle | <<locked>> | 92% | 56,492 psi | 89% | 2995 fps | 100% |
| Shooters World Precision | <<locked>> | 96% | 57,159 psi | 90% | 2995 fps | 100% |
| Shooters World Tactical Rifle | <<locked>> | 84% | 55,999 psi | 88% | 2930 fps | 99.9% |
| SNPE Vectan BA6 1/2 | <<locked>> | 82% | 57,348 psi | 90% | 2608 fps | 100% |
| SNPE Vectan SP 10 | <<locked>> | 82% | 55,245 psi | 87% | 2953 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 98% | 56,362 psi | 88% | 3051 fps | 99.6% |
| SNPE Vectan SP 3 | <<locked>> | 84% | 55,579 psi | 87% | 2910 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 90% | 55,013 psi | 86% | 2959 fps | 98.2% |
| SNPE Vectan SP 9 | <<locked>> | 92% | 55,651 psi | 87% | 2989 fps | 99.5% |
| SNPE Vectan Tubal 3000 | <<locked>> | 90% | 54,404 psi | 85% | 2861 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 98% | 57,696 psi | 90% | 2900 fps | 100% |
| SNPE Vectan Tubal 7000ᴾ | <<locked>> | 100% | 53,287 psi | 84% | 2877 fps | 95.8% |
| Somchem S321 | <<locked>> | 86% | 54,317 psi | 85% | 2959 fps | 99.9% |
| Somchem S335 | <<locked>> | 92% | 56,768 psi | 89% | 2904 fps | 100% |
| Somchem S341 | <<locked>> | 90% | 54,650 psi | 86% | 2956 fps | 99.4% |
| Somchem S355 | <<locked>> | 98% | 54,607 psi | 86% | 2982 fps | 99.7% |
| Somchem S365ᴾ | <<locked>> | 100% | 42,264 psi | 66% | 2867 fps | 99.2% |
| Vihtavuori N130 | <<locked>> | 88% | 57,667 psi | 90% | 2877 fps | 100% |
| Vihtavuori N133 | <<locked>> | 90% | 54,433 psi | 85% | 2848 fps | 100% |
| Vihtavuori N135 | <<locked>> | 94% | 55,405 psi | 87% | 2930 fps | 100% |
| Vihtavuori N140 | <<locked>> | 94% | 56,869 psi | 89% | 2946 fps | 100% |
| Vihtavuori N150ᴾ | <<locked>> | 100% | 56,376 psi | 88% | 2966 fps | 100% |
| Vihtavuori N160ᴾ | <<locked>> | 100% | 50,140 psi | 79% | 2927 fps | 97.9% |
| Vihtavuori N530 | <<locked>> | 90% | 57,116 psi | 90% | 2976 fps | 100% |
| Vihtavuori N540 | <<locked>> | 94% | 54,911 psi | 86% | 2943 fps | 100% |
| Vihtavuori N550ᴾ | <<locked>> | 100% | 49,182 psi | 77% | 2927 fps | 97.6% |
| Winchester 6.5 StaBALLᴾ | <<locked>> | 100% | 51,314 psi | 80% | 2913 fps | 99.5% |
| Winchester 748 | <<locked>> | 90% | 56,478 psi | 89% | 3022 fps | 100% |
| Winchester StaBALL Match | <<locked>> | 92% | 55,448 psi | 87% | 2999 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% | 42,206 psi | 66% | 2684 fps | 100% |
| Accurate 2460 | <<locked>> | 80% | 46,151 psi | 72% | 2789 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 34,461 psi | 54% | 2579 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 41,321 psi | 65% | 2736 fps | 99.6% |
| Accurate 4064 | <<locked>> | 80% | 32,590 psi | 51% | 2559 fps | 98.7% |
| Accurate 4350 | <<locked>> | 94% | 38,232 psi | 60% | 2743 fps | 95.1% |
| Accurate LT-30 | <<locked>> | 80% | 50,879 psi | 80% | 2772 fps | 100% |
| Accurate LT-32 | <<locked>> | 80% | 51,256 psi | 80% | 2795 fps | 100% |
| ADI AR 2206H | <<locked>> | 80% | 38,928 psi | 61% | 2687 fps | 96.7% |
| ADI AR 2208 | <<locked>> | 84% | 37,623 psi | 59% | 2638 fps | 95.5% |
| ADI AR 2219 | <<locked>> | 80% | 51,242 psi | 80% | 2890 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 80% | 41,046 psi | 64% | 2707 fps | 98.4% |
| Alliant AR-Comp | <<locked>> | 80% | 40,118 psi | 63% | 2710 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 80% | 47,659 psi | 75% | 2913 fps | 99.1% |
| Alliant Power Pro 2000-MR | 53.2 gr | 84% | 40,248 psi | 63% | 2812 fps | 95.9% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 32,126 psi | 50% | 2543 fps | 95.4% |
| Alliant Reloder-10x | <<locked>> | 80% | 47,979 psi | 75% | 2789 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 82% | 37,173 psi | 58% | 2667 fps | 95.6% |
| Alliant Reloder-16 | <<locked>> | 94% | 39,175 psi | 61% | 2762 fps | 95.3% |
| Alliant Reloder-17 | <<locked>> | 86% | 34,055 psi | 53% | 2667 fps | 95.3% |
| Baschieri & Pellagri 106 | <<locked>> | 80% | 50,053 psi | 78% | 2766 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 37,884 psi | 59% | 2680 fps | 95.1% |
| Bofors RP3 | <<locked>> | 80% | 31,299 psi | 49% | 2536 fps | 95.2% |
| Hodgdon Benchmark | <<locked>> | 80% | 43,105 psi | 68% | 2707 fps | 99.1% |
| Hodgdon BL-C2 | <<locked>> | 80% | 39,189 psi | 61% | 2717 fps | 98.5% |
| Hodgdon CFE223 | <<locked>> | 80% | 43,236 psi | 68% | 2854 fps | 97.3% |
| Hodgdon H322 | <<locked>> | 80% | 46,818 psi | 73% | 2818 fps | 100% |
| Hodgdon H335 | <<locked>> | 80% | 47,863 psi | 75% | 2844 fps | 100% |
| Hodgdon H380 | <<locked>> | 86% | 40,016 psi | 63% | 2717 fps | 95% |
| Hodgdon H4895 | <<locked>> | 80% | 39,204 psi | 61% | 2697 fps | 97.4% |
| Hodgdon Hybrid 100V | <<locked>> | 92% | 33,286 psi | 52% | 2589 fps | 95.1% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 35,099 psi | 55% | 2654 fps | 96.6% |
| Hodgdon TrailBoss | <<locked>> | 80% | 25,541 psi | 40% | 1608 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 37,724 psi | 59% | 2648 fps | 96.9% |
| IMR 3031 | <<locked>> | 80% | 38,276 psi | 60% | 2707 fps | 100% |
| IMR 4064 | <<locked>> | 82% | 37,115 psi | 58% | 2621 fps | 95.6% |
| IMR 4166 Enduron | <<locked>> | 90% | 51,634 psi | 81% | 2867 fps | 95.5% |
| IMR 4198 | <<locked>> | 80% | 48,718 psi | 76% | 2756 fps | 100% |
| IMR 4451 Enduron | <<locked>> | 96% | 50,763 psi | 80% | 2881 fps | 95.2% |
| IMR 4831 | <<locked>> | 96% | 39,581 psi | 62% | 2753 fps | 95.7% |
| IMR 4895 | <<locked>> | 80% | 35,563 psi | 56% | 2641 fps | 95.7% |
| IMR 8208 XBR | <<locked>> | 80% | 41,046 psi | 64% | 2707 fps | 98.4% |
| Lovex D073.5 | <<locked>> | 80% | 45,992 psi | 72% | 2795 fps | 99.7% |
| Lovex D073.6 | <<locked>> | 80% | 37,144 psi | 58% | 2661 fps | 98.9% |
| Lovex S060 | <<locked>> | 80% | 39,610 psi | 62% | 2635 fps | 96.9% |
| Lovex S062 | <<locked>> | 80% | 34,272 psi | 54% | 2569 fps | 96.7% |
| Lovex S065 | <<locked>> | 94% | 43,642 psi | 68% | 2762 fps | 95.1% |
| Norma 200 | <<locked>> | 80% | 54,056 psi | 85% | 2854 fps | 100% |
| Norma 201 | <<locked>> | 80% | 38,072 psi | 60% | 2644 fps | 97.8% |
| Norma 202 | <<locked>> | 80% | 38,145 psi | 60% | 2657 fps | 99.5% |
| Norma 203B | <<locked>> | 80% | 34,156 psi | 54% | 2595 fps | 95.1% |
| Norma URP | <<locked>> | 94% | 38,914 psi | 61% | 2749 fps | 95.1% |
| Ramshot Big Game | <<locked>> | 82% | 36,143 psi | 57% | 2664 fps | 95.6% |
| Ramshot TAC | <<locked>> | 82% | 43,830 psi | 69% | 2756 fps | 95.3% |
| Ramshot Wild Boar | <<locked>> | 80% | 40,190 psi | 63% | 2720 fps | 97% |
| Ramshot X-Terminator | <<locked>> | 80% | 44,469 psi | 70% | 2753 fps | 97.9% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 25,701 psi | 40% | 1647 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 46,079 psi | 72% | 2799 fps | 99.8% |
| ReloadSwiss RS 50 | <<locked>> | 90% | 46,514 psi | 73% | 2818 fps | 95% |
| ReloadSwiss RS 52 | 49.1 gr | 80% | 35,839 psi | 56% | 2700 fps | 95% |
| ReloadSwiss RS 60 | 49.9 gr | 80% | 29,602 psi | 46% | 2549 fps | 95.8% |
| ReloadSwiss RS 62 | <<locked>> | 96% | 41,075 psi | 64% | 2822 fps | 95.6% |
| ReloadSwiss RS 70 | <<locked>> | 98% | 45,208 psi | 71% | 2904 fps | 95.8% |
| Rottweil R 901 | <<locked>> | 80% | 41,582 psi | 65% | 2697 fps | 99.7% |
| Rottweil R 902 | <<locked>> | 80% | 36,114 psi | 57% | 2589 fps | 97.2% |
| Rottweil R 903 | <<locked>> | 82% | 31,604 psi | 50% | 2536 fps | 95% |
| Shooters World Long Rifle | <<locked>> | 94% | 43,642 psi | 68% | 2762 fps | 95.1% |
| Shooters World Match Rifle | <<locked>> | 80% | 37,144 psi | 58% | 2661 fps | 98.9% |
| Shooters World Precision | <<locked>> | 80% | 34,272 psi | 54% | 2569 fps | 96.7% |
| Shooters World Tactical Rifle | <<locked>> | 80% | 48,805 psi | 76% | 2818 fps | 99.3% |
| SNPE Vectan BA6 1/2 | <<locked>> | 80% | 54,650 psi | 86% | 2572 fps | 100% |
| SNPE Vectan SP 10 | <<locked>> | 80% | 51,866 psi | 81% | 2904 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 84% | 35,230 psi | 55% | 2648 fps | 95.3% |
| SNPE Vectan SP 3 | <<locked>> | 80% | 48,820 psi | 77% | 2812 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 82% | 41,539 psi | 65% | 2720 fps | 95.3% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 37,391 psi | 59% | 2648 fps | 96.2% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 39,711 psi | 62% | 2612 fps | 99.6% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 32,619 psi | 51% | 2467 fps | 99.2% |
| SNPE Vectan Tubal 7000 | <<locked>> | 98% | 49,734 psi | 78% | 2822 fps | 95.1% |
| Somchem S321 | <<locked>> | 80% | 44,019 psi | 69% | 2782 fps | 99.1% |
| Somchem S335 | <<locked>> | 80% | 39,276 psi | 62% | 2615 fps | 99.9% |
| Somchem S341 | <<locked>> | 80% | 38,595 psi | 60% | 2664 fps | 96.5% |
| Somchem S355 | <<locked>> | 82% | 32,634 psi | 51% | 2546 fps | 95.1% |
| Somchem S365 | <<locked>> | 90% | 30,429 psi | 48% | 2575 fps | 95.5% |
| Vihtavuori N130 | <<locked>> | 80% | 45,136 psi | 71% | 2694 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 39,929 psi | 63% | 2615 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 35,128 psi | 55% | 2589 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 36,143 psi | 57% | 2592 fps | 99.4% |
| Vihtavuori N150 | <<locked>> | 80% | 29,037 psi | 46% | 2431 fps | 95.3% |
| Vihtavuori N160 | <<locked>> | 94% | 40,959 psi | 64% | 2753 fps | 95.7% |
| Vihtavuori N530 | <<locked>> | 80% | 40,886 psi | 64% | 2700 fps | 98.4% |
| Vihtavuori N540 | <<locked>> | 80% | 34,650 psi | 54% | 2572 fps | 98.8% |
| Vihtavuori N550 | <<locked>> | 94% | 40,059 psi | 63% | 2753 fps | 95.2% |
| Winchester 6.5 StaBALL | <<locked>> | 88% | 34,084 psi | 53% | 2566 fps | 95.5% |
| Winchester 748 | <<locked>> | 80% | 39,987 psi | 63% | 2740 fps | 98.9% |
| Winchester StaBALL Match | <<locked>> | 80% | 36,738 psi | 58% | 2654 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 96 powders for .300 RCM loaded with the .308 | 150gr | Fox Classic Hunter. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 3,143 fps; across all powders the maximum-charge window runs from 1,801 fps to 3,143 fps. Accurate 4350 gives the best case fill at 100 %, and 96 of the 96 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (440 MPa), the top charges use 54–90 %, leaving at least 10 % headroom. The 150.0 gr projectile in 0.308" calls for a 1:12.0 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, ReloadSwiss RS 60 rank at the top here: for .300 RCM with the .308 | 150gr | Fox Classic Hunter 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.