Load Specifications
Load data in caliber .300 RCM with .308 | 170gr | Swift A-Frame bullet and 98 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Alliant Reloder-17, ReloadSwiss RS 60 and Winchester 760.
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>> | 84% | 57,508 psi | 90% | 2756 fps | 100% |
| Accurate 2495 | <<locked>> | 88% | 56,768 psi | 89% | 2785 fps | 100% |
| Accurate 2520 | <<locked>> | 82% | 54,534 psi | 85% | 2802 fps | 100% |
| Accurate 2700 | <<locked>> | 88% | 55,347 psi | 87% | 2789 fps | 97.4% |
| Accurate 3100ᴾ | <<locked>> | 100% | 43,540 psi | 68% | 2690 fps | 96.9% |
| Accurate 4064 | <<locked>> | 90% | 56,608 psi | 89% | 2835 fps | 100% |
| Accurate 4350 | <<locked>> | 98% | 56,550 psi | 89% | 2923 fps | 99.9% |
| ADI AR 2206H | <<locked>> | 86% | 56,681 psi | 89% | 2867 fps | 100% |
| ADI AR 2208 | <<locked>> | 92% | 57,653 psi | 90% | 2864 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 84% | 55,506 psi | 87% | 2812 fps | 100% |
| Alliant AR-Comp | <<locked>> | 84% | 56,811 psi | 89% | 2785 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 88% | 56,492 psi | 89% | 2989 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 90% | 54,404 psi | 85% | 2838 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 88% | 54,984 psi | 86% | 2861 fps | 99.9% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 57,682 psi | 90% | 2979 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 94% | 55,216 psi | 87% | 2959 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 41,336 psi | 65% | 2720 fps | 99.4% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 46,499 psi | 73% | 2887 fps | 98.9% |
| Baschieri & Pellagri 107 | <<locked>> | 86% | 56,652 psi | 89% | 2884 fps | 99.9% |
| Bofors RP3 | <<locked>> | 90% | 55,172 psi | 86% | 2854 fps | 100% |
| Bofors RP7 | <<locked>> | 94% | 55,042 psi | 86% | 2825 fps | 97.7% |
| Hodgdon Benchmark | <<locked>> | 84% | 57,072 psi | 89% | 2795 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 84% | 55,027 psi | 86% | 2844 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 82% | 57,305 psi | 90% | 2949 fps | 100% |
| Hodgdon H380 | <<locked>> | 90% | 55,941 psi | 88% | 2867 fps | 99.6% |
| Hodgdon H414 | <<locked>> | 96% | 55,796 psi | 87% | 2920 fps | 98.4% |
| Hodgdon H4350 | <<locked>> | 94% | 56,043 psi | 88% | 2881 fps | 97.2% |
| Hodgdon H4895 | <<locked>> | 86% | 57,246 psi | 90% | 2874 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 53,809 psi | 84% | 2851 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 88% | 57,029 psi | 89% | 2910 fps | 100% |
| Hodgdon Superformance | <<locked>> | 96% | 56,217 psi | 88% | 2959 fps | 98.2% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,795 psi | 56% | 1739 fps | 100% |
| Hodgdon VARGET | <<locked>> | 86% | 54,868 psi | 86% | 2825 fps | 100% |
| IMR 3031 | <<locked>> | 86% | 57,638 psi | 90% | 2854 fps | 100% |
| IMR 4064 | <<locked>> | 90% | 57,305 psi | 90% | 2851 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 88% | 56,927 psi | 89% | 2831 fps | 98.4% |
| IMR 4350 | <<locked>> | 98% | 55,361 psi | 87% | 2851 fps | 97.7% |
| IMR 4451 Enduron | <<locked>> | 94% | 56,913 psi | 89% | 2858 fps | 98.3% |
| IMR 4831ᴾ | <<locked>> | 100% | 57,014 psi | 89% | 2913 fps | 99.9% |
| IMR 4895 | <<locked>> | 88% | 56,405 psi | 88% | 2890 fps | 100% |
| IMR 8208 XBR | <<locked>> | 84% | 55,506 psi | 87% | 2812 fps | 100% |
| Lovex D073.6 | <<locked>> | 86% | 56,782 psi | 89% | 2841 fps | 100% |
| Lovex S060 | <<locked>> | 86% | 55,956 psi | 88% | 2792 fps | 100% |
| Lovex S062 | <<locked>> | 90% | 57,101 psi | 89% | 2844 fps | 100% |
| Lovex S065 | <<locked>> | 96% | 56,231 psi | 88% | 2848 fps | 99.2% |
| Lovex S070 | <<locked>> | 98% | 57,479 psi | 90% | 2887 fps | 98.7% |
| Norma 201 | <<locked>> | 86% | 55,376 psi | 87% | 2808 fps | 100% |
| Norma 202 | <<locked>> | 86% | 55,941 psi | 88% | 2808 fps | 100% |
| Norma 203B | <<locked>> | 90% | 57,508 psi | 90% | 2894 fps | 100% |
| Norma 204 | <<locked>> | 98% | 56,086 psi | 88% | 2904 fps | 96.7% |
| Norma MRPᴾ | <<locked>> | 100% | 46,325 psi | 73% | 2841 fps | 96.4% |
| Norma URP | <<locked>> | 98% | 55,579 psi | 87% | 2910 fps | 99.8% |
| Ramshot Big Game | <<locked>> | 88% | 54,607 psi | 86% | 2871 fps | 100% |
| Ramshot Hunter | <<locked>> | 98% | 54,317 psi | 85% | 2907 fps | 98.8% |
| Ramshot TAC | <<locked>> | 84% | 55,709 psi | 87% | 2835 fps | 99.3% |
| Ramshot Wild Boar | <<locked>> | 84% | 55,535 psi | 87% | 2851 fps | 100% |
| Ramshot X-Terminator | <<locked>> | 82% | 56,347 psi | 88% | 2815 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,274 psi | 57% | 1778 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 90% | 56,246 psi | 88% | 2851 fps | 98.8% |
| ReloadSwiss RS 52 | <<locked>> | 86% | 55,535 psi | 87% | 2927 fps | 99.9% |
| ReloadSwiss RS 60 | <<locked>> | 92% | 55,042 psi | 86% | 2959 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 98% | 56,289 psi | 88% | 2946 fps | 99.8% |
| ReloadSwiss RS 70 | <<locked>> | 98% | 55,637 psi | 87% | 2976 fps | 99.7% |
| Rottweil R 901 | <<locked>> | 84% | 56,463 psi | 88% | 2789 fps | 100% |
| Rottweil R 902 | <<locked>> | 88% | 56,014 psi | 88% | 2808 fps | 100% |
| Rottweil R 903 | <<locked>> | 92% | 55,013 psi | 86% | 2844 fps | 100% |
| Rottweil R 907 | <<locked>> | 94% | 55,042 psi | 86% | 2825 fps | 97.7% |
| Shooters World Long Rifle | <<locked>> | 96% | 56,231 psi | 88% | 2848 fps | 99.2% |
| Shooters World Match Rifle | <<locked>> | 86% | 56,782 psi | 89% | 2841 fps | 100% |
| Shooters World Precision | <<locked>> | 90% | 57,101 psi | 89% | 2844 fps | 100% |
| Shooters World SW4350 | <<locked>> | 98% | 57,479 psi | 90% | 2887 fps | 98.7% |
| SNPE Vectan SP 11 | <<locked>> | 92% | 56,623 psi | 89% | 2904 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 84% | 54,259 psi | 85% | 2812 fps | 99.4% |
| SNPE Vectan SP 9 | <<locked>> | 86% | 55,085 psi | 86% | 2835 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 86% | 56,695 psi | 89% | 2743 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 92% | 56,956 psi | 89% | 2743 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 96% | 56,623 psi | 89% | 2805 fps | 98.3% |
| Somchem S321 | <<locked>> | 82% | 56,768 psi | 89% | 2844 fps | 100% |
| Somchem S335 | <<locked>> | 86% | 56,115 psi | 88% | 2743 fps | 100% |
| Somchem S341 | <<locked>> | 84% | 53,940 psi | 85% | 2802 fps | 100% |
| Somchem S355 | <<locked>> | 92% | 55,071 psi | 86% | 2841 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 53,722 psi | 84% | 2913 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 49,705 psi | 78% | 2792 fps | 96.6% |
| Vihtavuori N130 | <<locked>> | 82% | 56,391 psi | 88% | 2703 fps | 100% |
| Vihtavuori N133 | <<locked>> | 86% | 56,985 psi | 89% | 2726 fps | 100% |
| Vihtavuori N135 | <<locked>> | 88% | 55,738 psi | 87% | 2769 fps | 100% |
| Vihtavuori N140 | <<locked>> | 88% | 56,608 psi | 89% | 2789 fps | 100% |
| Vihtavuori N150 | <<locked>> | 94% | 56,536 psi | 89% | 2818 fps | 100% |
| Vihtavuori N160 | <<locked>> | 96% | 54,534 psi | 85% | 2854 fps | 99.7% |
| Vihtavuori N530 | <<locked>> | 84% | 56,057 psi | 88% | 2815 fps | 100% |
| Vihtavuori N540 | <<locked>> | 88% | 54,694 psi | 86% | 2785 fps | 100% |
| Vihtavuori N550 | <<locked>> | 98% | 57,072 psi | 89% | 2913 fps | 99.8% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 45,818 psi | 72% | 2799 fps | 99.3% |
| Winchester 6.5 StaBALL | <<locked>> | 96% | 54,418 psi | 85% | 2828 fps | 100% |
| Winchester 748 | <<locked>> | 84% | 56,144 psi | 88% | 2861 fps | 100% |
| Winchester 760 | <<locked>> | 96% | 55,796 psi | 87% | 2920 fps | 98.4% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 37,101 psi | 58% | 2733 fps | 99.5% |
| Winchester StaBALL Match | <<locked>> | 86% | 55,056 psi | 86% | 2844 fps | 100% |
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% | 50,952 psi | 80% | 2667 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 43,787 psi | 69% | 2598 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 50,792 psi | 80% | 2749 fps | 100% |
| Accurate 2700 | <<locked>> | 82% | 45,426 psi | 71% | 2621 fps | 95.3% |
| Accurate 3100 | <<locked>> | 96% | 38,014 psi | 60% | 2582 fps | 95.2% |
| Accurate 4064 | <<locked>> | 80% | 41,394 psi | 65% | 2595 fps | 100% |
| Accurate 4350 | <<locked>> | 82% | 32,735 psi | 51% | 2477 fps | 95.3% |
| ADI AR 2206H | <<locked>> | 80% | 47,007 psi | 74% | 2710 fps | 99.6% |
| ADI AR 2208 | <<locked>> | 80% | 39,929 psi | 63% | 2559 fps | 98.1% |
| ADI Benchmark 8208 | <<locked>> | 80% | 49,052 psi | 77% | 2713 fps | 100% |
| Alliant AR-Comp | <<locked>> | 80% | 49,763 psi | 78% | 2694 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 42,888 psi | 67% | 2746 fps | 98.7% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 39,653 psi | 62% | 2582 fps | 99.2% |
| Alliant Reloder-15 | <<locked>> | 80% | 42,627 psi | 67% | 2648 fps | 98.7% |
| Alliant Reloder-16 | <<locked>> | 82% | 32,880 psi | 52% | 2487 fps | 95.3% |
| Alliant Reloder-17 | 53.5 gr | 80% | 34,418 psi | 54% | 2556 fps | 97.8% |
| Alliant Reloder-23 | <<locked>> | 88% | 28,631 psi | 45% | 2395 fps | 95% |
| Alliant Reloder-26 | <<locked>> | 92% | 35,070 psi | 55% | 2631 fps | 95.4% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 46,369 psi | 73% | 2717 fps | 99% |
| Bofors RP3 | <<locked>> | 80% | 39,465 psi | 62% | 2589 fps | 99.2% |
| Bofors RP7 | <<locked>> | 88% | 45,585 psi | 71% | 2664 fps | 95.6% |
| Hodgdon Benchmark | <<locked>> | 80% | 50,604 psi | 79% | 2700 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 48,124 psi | 75% | 2740 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 80% | 53,403 psi | 84% | 2890 fps | 99.9% |
| Hodgdon H380 | <<locked>> | 80% | 40,277 psi | 63% | 2592 fps | 97.2% |
| Hodgdon H414 | <<locked>> | 88% | 42,656 psi | 67% | 2694 fps | 95.6% |
| Hodgdon H4350 | <<locked>> | 88% | 46,456 psi | 73% | 2717 fps | 95.1% |
| Hodgdon H4895 | <<locked>> | 80% | 47,442 psi | 74% | 2720 fps | 99.8% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 28,326 psi | 44% | 2336 fps | 95.3% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 43,410 psi | 68% | 2690 fps | 99.7% |
| Hodgdon Superformance | <<locked>> | 90% | 45,426 psi | 71% | 2772 fps | 95.8% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,672 psi | 42% | 1552 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 45,411 psi | 71% | 2671 fps | 99.7% |
| IMR 3031 | <<locked>> | 80% | 47,427 psi | 74% | 2710 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 41,945 psi | 66% | 2595 fps | 98.7% |
| IMR 4166 Enduron | <<locked>> | 80% | 44,411 psi | 70% | 2615 fps | 95.9% |
| IMR 4350 | <<locked>> | 92% | 45,919 psi | 72% | 2694 fps | 95.7% |
| IMR 4451 Enduron | <<locked>> | 84% | 41,901 psi | 66% | 2592 fps | 95.1% |
| IMR 4831 | <<locked>> | 84% | 33,910 psi | 53% | 2490 fps | 95.8% |
| IMR 4895 | <<locked>> | 80% | 43,700 psi | 68% | 2677 fps | 99.3% |
| IMR 8208 XBR | <<locked>> | 80% | 49,052 psi | 77% | 2713 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 46,340 psi | 73% | 2687 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 46,702 psi | 73% | 2644 fps | 99.6% |
| Lovex S062 | <<locked>> | 80% | 41,930 psi | 66% | 2595 fps | 99.7% |
| Lovex S065 | <<locked>> | 82% | 36,680 psi | 57% | 2490 fps | 95.1% |
| Lovex S070 | <<locked>> | 88% | 42,105 psi | 66% | 2625 fps | 95.6% |
| Norma 201 | <<locked>> | 80% | 46,050 psi | 72% | 2661 fps | 99.9% |
| Norma 202 | <<locked>> | 80% | 46,238 psi | 72% | 2661 fps | 100% |
| Norma 203B | <<locked>> | 80% | 42,018 psi | 66% | 2635 fps | 99% |
| Norma 204 | <<locked>> | 94% | 49,081 psi | 77% | 2785 fps | 95.1% |
| Norma MRP | <<locked>> | 98% | 43,366 psi | 68% | 2782 fps | 95.5% |
| Norma URP | <<locked>> | 82% | 32,982 psi | 52% | 2477 fps | 95.2% |
| Ramshot Big Game | <<locked>> | 80% | 41,669 psi | 65% | 2651 fps | 98.9% |
| Ramshot Hunter | <<locked>> | 88% | 39,117 psi | 61% | 2625 fps | 95.4% |
| Ramshot TAC | <<locked>> | 80% | 48,994 psi | 77% | 2723 fps | 98.4% |
| Ramshot Wild Boar | <<locked>> | 80% | 48,675 psi | 76% | 2746 fps | 99.7% |
| Ramshot X-Terminator | <<locked>> | 80% | 52,736 psi | 83% | 2762 fps | 99.9% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,992 psi | 42% | 1588 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 40,524 psi | 64% | 2572 fps | 95.5% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 45,049 psi | 71% | 2749 fps | 99.1% |
| ReloadSwiss RS 60 | 53.5 gr | 80% | 36,622 psi | 57% | 2621 fps | 99.8% |
| ReloadSwiss RS 62 | <<locked>> | 84% | 34,708 psi | 54% | 2546 fps | 95.6% |
| ReloadSwiss RS 70 | <<locked>> | 86% | 37,057 psi | 58% | 2612 fps | 95.6% |
| Rottweil R 901 | <<locked>> | 80% | 49,937 psi | 78% | 2694 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 43,685 psi | 68% | 2608 fps | 99.8% |
| Rottweil R 903 | <<locked>> | 80% | 37,188 psi | 58% | 2533 fps | 98.6% |
| Rottweil R 907 | <<locked>> | 88% | 45,585 psi | 71% | 2664 fps | 95.6% |
| Shooters World Long Rifle | <<locked>> | 82% | 36,680 psi | 57% | 2490 fps | 95.1% |
| Shooters World Match Rifle | <<locked>> | 80% | 46,340 psi | 73% | 2687 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 41,930 psi | 66% | 2595 fps | 99.7% |
| Shooters World SW4350 | <<locked>> | 88% | 42,105 psi | 66% | 2625 fps | 95.6% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 38,058 psi | 60% | 2582 fps | 98.2% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 47,413 psi | 74% | 2700 fps | 98.5% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 45,339 psi | 71% | 2677 fps | 99.4% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 47,166 psi | 74% | 2608 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 39,436 psi | 62% | 2474 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 86% | 40,901 psi | 64% | 2536 fps | 95% |
| Somchem S321 | <<locked>> | 80% | 53,301 psi | 84% | 2795 fps | 100% |
| Somchem S335 | <<locked>> | 80% | 46,905 psi | 74% | 2608 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 47,181 psi | 74% | 2697 fps | 99.6% |
| Somchem S355 | <<locked>> | 80% | 38,000 psi | 60% | 2539 fps | 98.6% |
| Somchem S365 | <<locked>> | 80% | 27,673 psi | 43% | 2372 fps | 96.6% |
| Somchem S385 | <<locked>> | 96% | 43,526 psi | 68% | 2684 fps | 95% |
| Vihtavuori N130 | <<locked>> | 80% | 53,127 psi | 83% | 2661 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 47,543 psi | 75% | 2598 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 43,439 psi | 68% | 2589 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 43,888 psi | 69% | 2598 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 36,056 psi | 56% | 2474 fps | 99.2% |
| Vihtavuori N160 | <<locked>> | 82% | 34,461 psi | 54% | 2480 fps | 95.7% |
| Vihtavuori N530 | <<locked>> | 80% | 49,124 psi | 77% | 2710 fps | 100% |
| Vihtavuori N540 | <<locked>> | 80% | 42,337 psi | 66% | 2592 fps | 100% |
| Vihtavuori N550 | <<locked>> | 82% | 33,881 psi | 53% | 2480 fps | 95.2% |
| Vihtavuori N555 | <<locked>> | 88% | 30,821 psi | 48% | 2470 fps | 95.2% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 31,981 psi | 50% | 2402 fps | 97.1% |
| Winchester 748 | <<locked>> | 80% | 49,226 psi | 77% | 2759 fps | 100% |
| Winchester 760 | 57.6 gr | 88% | 42,859 psi | 67% | 2697 fps | 95.7% |
| Winchester StaBALL HD | <<locked>> | 92% | 28,601 psi | 45% | 2470 fps | 95.5% |
| Winchester StaBALL Match | <<locked>> | 80% | 44,904 psi | 70% | 2680 fps | 99.7% |
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 117 powders for .300 RCM loaded with the .308 | 170gr | Swift A-Frame. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 2,989 fps; across all powders the maximum-charge window runs from 1,739 fps to 2,989 fps. Accurate 3100 gives the best case fill at 100 %, and 117 of the 117 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (440 MPa), the top charges use 56–90 %, leaving at least 10 % headroom. The 170.0 gr projectile in 0.308" calls for a 1:6.0 twist; slower twists will usually not stabilise this weight. Accurate 3100, ADI AR 2209, ADI AR 2213 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 Reloder-17, ReloadSwiss RS 60, Winchester 760 rank at the top here: for .300 RCM with the .308 | 170gr | Swift A-Frame they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, ADI AR 2213, Alliant Reloder-22, Alliant Reloder-25 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.