Load Specifications
Load data in caliber .338 Win Mag. with .338 | 185gr | 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.
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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>> | 90% | 56,101 psi | 90% | 2831 fps | 100% |
| Accurate 2460 | <<locked>> | 86% | 54,708 psi | 88% | 2858 fps | 100% |
| Accurate 2495 | <<locked>> | 94% | 53,055 psi | 85% | 2841 fps | 100% |
| Accurate 2520 | <<locked>> | 90% | 54,433 psi | 87% | 2900 fps | 100% |
| Accurate 4064 | <<locked>> | 98% | 56,231 psi | 90% | 2927 fps | 100% |
| Accurate 4350ᴾ | <<locked>> | 100% | 45,121 psi | 72% | 2818 fps | 96.8% |
| Accurate LT-30 | <<locked>> | 84% | 56,202 psi | 90% | 2782 fps | 100% |
| Accurate LT-32 | <<locked>> | 82% | 53,258 psi | 85% | 2759 fps | 100% |
| ADI AR 2206H | <<locked>> | 92% | 55,216 psi | 89% | 2920 fps | 99.4% |
| ADI AR 2208 | <<locked>> | 98% | 56,202 psi | 90% | 2913 fps | 99.1% |
| ADI AR 2219 | <<locked>> | 82% | 53,084 psi | 85% | 2851 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 90% | 54,723 psi | 88% | 2881 fps | 99.8% |
| Alliant AR-Comp | <<locked>> | 90% | 54,389 psi | 87% | 2864 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 86% | 56,028 psi | 90% | 2982 fps | 99.7% |
| Alliant Power Pro 2000-MR | <<locked>> | 94% | 54,795 psi | 88% | 3028 fps | 98.9% |
| Alliant Reloder- TS 15.5 | <<locked>> | 98% | 55,434 psi | 89% | 2933 fps | 99.8% |
| Alliant Reloder-10x | <<locked>> | 86% | 56,130 psi | 90% | 2844 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 96% | 56,304 psi | 90% | 2956 fps | 99.2% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 45,469 psi | 73% | 2831 fps | 97% |
| Alliant Reloder-17ᴾ | <<locked>> | 100% | 52,707 psi | 85% | 2992 fps | 99.6% |
| Baschieri & Pellagri 106 | <<locked>> | 84% | 55,274 psi | 89% | 2776 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 92% | 55,288 psi | 89% | 2933 fps | 98.7% |
| Bofors RP3 | <<locked>> | 98% | 55,825 psi | 90% | 2949 fps | 99.8% |
| Hodgdon Benchmark | <<locked>> | 88% | 53,490 psi | 86% | 2818 fps | 99.9% |
| Hodgdon BL-C2 | <<locked>> | 90% | 53,243 psi | 85% | 2904 fps | 99.9% |
| Hodgdon CFE223 | <<locked>> | 88% | 55,376 psi | 89% | 3002 fps | 99.2% |
| Hodgdon H322 | <<locked>> | 88% | 54,621 psi | 88% | 2874 fps | 100% |
| Hodgdon H335 | <<locked>> | 84% | 56,217 psi | 90% | 2904 fps | 100% |
| Hodgdon H380 | <<locked>> | 96% | 53,722 psi | 86% | 2904 fps | 97.9% |
| Hodgdon H414ᴾ | <<locked>> | 100% | 54,665 psi | 88% | 2969 fps | 96% |
| Hodgdon H4198 | <<locked>> | 82% | 54,476 psi | 87% | 2779 fps | 100% |
| Hodgdon H4895 | <<locked>> | 92% | 55,695 psi | 89% | 2933 fps | 99.7% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 41,394 psi | 66% | 2710 fps | 97.5% |
| Hodgdon LEVERevolution | <<locked>> | 96% | 54,244 psi | 87% | 2956 fps | 99.8% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 34,505 psi | 55% | 1749 fps | 100% |
| Hodgdon VARGET | <<locked>> | 96% | 55,912 psi | 90% | 2917 fps | 99.7% |
| IMR 3031 | <<locked>> | 94% | 53,055 psi | 85% | 2894 fps | 100% |
| IMR 4064 | <<locked>> | 98% | 54,636 psi | 88% | 2881 fps | 99% |
| IMR 4166 Enduron | <<locked>> | 98% | 54,868 psi | 88% | 2848 fps | 95.8% |
| IMR 4198 | <<locked>> | 84% | 53,316 psi | 85% | 2759 fps | 100% |
| IMR 4451 Enduronᴾ | <<locked>> | 100% | 55,506 psi | 89% | 2890 fps | 95.9% |
| IMR 4895 | <<locked>> | 94% | 54,273 psi | 87% | 2936 fps | 99.4% |
| IMR 8208 XBR | <<locked>> | 90% | 54,723 psi | 88% | 2881 fps | 99.8% |
| Lovex D073.5 | <<locked>> | 86% | 54,592 psi | 88% | 2864 fps | 100% |
| Lovex D073.6 | <<locked>> | 92% | 54,157 psi | 87% | 2897 fps | 100% |
| Lovex S060 | <<locked>> | 92% | 55,506 psi | 89% | 2851 fps | 99.4% |
| Lovex S062 | <<locked>> | 96% | 55,085 psi | 88% | 2897 fps | 99.9% |
| Lovex S065ᴾ | <<locked>> | 100% | 50,792 psi | 81% | 2825 fps | 96.5% |
| Norma 200 | <<locked>> | 82% | 55,622 psi | 89% | 2812 fps | 100% |
| Norma 201 | <<locked>> | 92% | 53,911 psi | 86% | 2867 fps | 99.8% |
| Norma 202 | <<locked>> | 92% | 54,331 psi | 87% | 2874 fps | 100% |
| Norma 203B | <<locked>> | 96% | 55,361 psi | 89% | 2943 fps | 99.4% |
| Norma URPᴾ | <<locked>> | 100% | 45,440 psi | 73% | 2818 fps | 96.7% |
| Ramshot Big Game | <<locked>> | 96% | 56,217 psi | 90% | 2972 fps | 99.4% |
| Ramshot TAC | <<locked>> | 90% | 55,201 psi | 89% | 2887 fps | 97.5% |
| Ramshot Wild Boar | <<locked>> | 90% | 54,244 psi | 87% | 2907 fps | 99.3% |
| Ramshot X-Terminator | <<locked>> | 88% | 55,985 psi | 90% | 2881 fps | 99.3% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 34,664 psi | 56% | 1788 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 86% | 54,360 psi | 87% | 2867 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 96% | 54,781 psi | 88% | 2887 fps | 96.6% |
| ReloadSwiss RS 52 | <<locked>> | 92% | 52,779 psi | 85% | 2969 fps | 98.8% |
| ReloadSwiss RS 60ᴾ | <<locked>> | 100% | 56,376 psi | 90% | 3061 fps | 100% |
| ReloadSwiss RS 62ᴾ | <<locked>> | 100% | 45,266 psi | 73% | 2838 fps | 96.5% |
| Rottweil R 901 | <<locked>> | 90% | 54,592 psi | 88% | 2851 fps | 100% |
| Rottweil R 902 | <<locked>> | 94% | 54,157 psi | 87% | 2861 fps | 99.8% |
| Rottweil R 903ᴾ | <<locked>> | 100% | 55,361 psi | 89% | 2933 fps | 99.7% |
| Shooters World Long Rifleᴾ | <<locked>> | 100% | 50,792 psi | 81% | 2825 fps | 96.5% |
| Shooters World Match Rifle | <<locked>> | 92% | 54,157 psi | 87% | 2897 fps | 100% |
| Shooters World Precision | <<locked>> | 96% | 55,085 psi | 88% | 2897 fps | 99.9% |
| Shooters World Tactical Rifle | <<locked>> | 84% | 54,259 psi | 87% | 2835 fps | 99.7% |
| SNPE Vectan BA6 1/2 | <<locked>> | 82% | 56,391 psi | 90% | 2533 fps | 100% |
| SNPE Vectan SP 10 | <<locked>> | 82% | 53,417 psi | 86% | 2858 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 98% | 54,186 psi | 87% | 2949 fps | 99.3% |
| SNPE Vectan SP 3 | <<locked>> | 84% | 53,751 psi | 86% | 2818 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 90% | 53,084 psi | 85% | 2858 fps | 97.7% |
| SNPE Vectan SP 9 | <<locked>> | 92% | 53,838 psi | 86% | 2890 fps | 99.2% |
| SNPE Vectan Tubal 3000 | <<locked>> | 92% | 56,130 psi | 90% | 2818 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 98% | 55,912 psi | 90% | 2812 fps | 100% |
| Somchem S321 | <<locked>> | 88% | 55,854 psi | 90% | 2913 fps | 99.9% |
| Somchem S335 | <<locked>> | 92% | 55,158 psi | 88% | 2815 fps | 100% |
| Somchem S341 | <<locked>> | 90% | 52,663 psi | 84% | 2858 fps | 99% |
| Somchem S355ᴾ | <<locked>> | 100% | 56,130 psi | 90% | 2936 fps | 99.7% |
| Somchem S365ᴾ | <<locked>> | 100% | 40,393 psi | 65% | 2762 fps | 98.7% |
| Unknown powderᴾ | <<locked>> | 100% | 49,980 psi | 80% | 2884 fps | 97% |
| Vihtavuori N130 | <<locked>> | 88% | 56,072 psi | 90% | 2789 fps | 100% |
| Vihtavuori N133 | <<locked>> | 92% | 56,101 psi | 90% | 2802 fps | 100% |
| Vihtavuori N135 | <<locked>> | 94% | 53,258 psi | 85% | 2835 fps | 100% |
| Vihtavuori N140 | <<locked>> | 94% | 54,897 psi | 88% | 2854 fps | 100% |
| Vihtavuori N150ᴾ | <<locked>> | 100% | 54,331 psi | 87% | 2867 fps | 99.9% |
| Vihtavuori N160ᴾ | <<locked>> | 100% | 47,935 psi | 77% | 2822 fps | 97.2% |
| Vihtavuori N530 | <<locked>> | 90% | 55,172 psi | 88% | 2877 fps | 99.9% |
| Vihtavuori N540 | <<locked>> | 94% | 53,127 psi | 85% | 2848 fps | 100% |
| Vihtavuori N550ᴾ | <<locked>> | 100% | 46,978 psi | 75% | 2822 fps | 96.8% |
| Winchester 6.5 StaBALLᴾ | <<locked>> | 100% | 49,327 psi | 79% | 2812 fps | 99.1% |
| Winchester 748 | <<locked>> | 88% | 55,201 psi | 89% | 2936 fps | 100% |
| Winchester 760ᴾ | <<locked>> | 100% | 54,665 psi | 88% | 2969 fps | 96% |
| Winchester StaBALL Match | <<locked>> | 86% | 55,390 psi | 89% | 2930 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 2015 | <<locked>> | 80% | 40,828 psi | 65% | 2595 fps | 100% |
| Accurate 2460 | <<locked>> | 80% | 44,440 psi | 71% | 2697 fps | 99.9% |
| Accurate 2495 | <<locked>> | 80% | 32,953 psi | 53% | 2490 fps | 99.9% |
| Accurate 2520 | <<locked>> | 80% | 38,116 psi | 61% | 2621 fps | 98.9% |
| Accurate 4064 | <<locked>> | 80% | 31,169 psi | 50% | 2467 fps | 98.2% |
| Accurate 4350 | <<locked>> | 96% | 39,059 psi | 63% | 2697 fps | 95.1% |
| Accurate LT-30 | <<locked>> | 80% | 49,719 psi | 80% | 2687 fps | 100% |
| Accurate LT-32 | <<locked>> | 80% | 50,096 psi | 80% | 2710 fps | 100% |
| ADI AR 2206H | <<locked>> | 80% | 37,652 psi | 60% | 2595 fps | 96% |
| ADI AR 2208 | <<locked>> | 86% | 38,682 psi | 62% | 2598 fps | 95.5% |
| ADI AR 2219 | <<locked>> | 80% | 49,545 psi | 79% | 2795 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 80% | 39,697 psi | 64% | 2612 fps | 97.9% |
| Alliant AR-Comp | <<locked>> | 80% | 38,609 psi | 62% | 2621 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 80% | 45,948 psi | 74% | 2815 fps | 98.6% |
| Alliant Power Pro 2000-MR | 60.7 gr | 84% | 38,856 psi | 62% | 2710 fps | 95% |
| Alliant Reloder- TS 15.5 | <<locked>> | 82% | 33,011 psi | 53% | 2507 fps | 95.5% |
| Alliant Reloder-10x | <<locked>> | 80% | 46,456 psi | 74% | 2700 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 84% | 38,218 psi | 61% | 2625 fps | 95.6% |
| Alliant Reloder-16 | <<locked>> | 96% | 40,059 psi | 64% | 2713 fps | 95.2% |
| Alliant Reloder-17 | <<locked>> | 88% | 34,983 psi | 56% | 2625 fps | 95.3% |
| Baschieri & Pellagri 106 | <<locked>> | 80% | 48,617 psi | 78% | 2680 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 82% | 39,233 psi | 63% | 2644 fps | 95.2% |
| Bofors RP3 | <<locked>> | 82% | 32,126 psi | 52% | 2500 fps | 95.3% |
| Hodgdon Benchmark | <<locked>> | 80% | 41,858 psi | 67% | 2615 fps | 98.8% |
| Hodgdon BL-C2 | <<locked>> | 80% | 37,637 psi | 60% | 2621 fps | 98% |
| Hodgdon CFE223 | <<locked>> | 80% | 41,582 psi | 67% | 2753 fps | 96.6% |
| Hodgdon H322 | <<locked>> | 80% | 42,047 psi | 67% | 2671 fps | 100% |
| Hodgdon H335 | <<locked>> | 80% | 48,791 psi | 78% | 2792 fps | 100% |
| Hodgdon H380 | <<locked>> | 88% | 41,118 psi | 66% | 2677 fps | 95% |
| Hodgdon H414 | <<locked>> | 98% | 50,836 psi | 82% | 2907 fps | 95.1% |
| Hodgdon H4198 | <<locked>> | 80% | 51,459 psi | 83% | 2736 fps | 100% |
| Hodgdon H4895 | <<locked>> | 80% | 37,898 psi | 61% | 2605 fps | 96.7% |
| Hodgdon Hybrid 100V | <<locked>> | 94% | 34,243 psi | 55% | 2549 fps | 95.1% |
| Hodgdon LEVERevolution | 55.5 gr | 80% | 31,937 psi | 51% | 2510 fps | 95% |
| Hodgdon TrailBoss | <<locked>> | 80% | 25,483 psi | 41% | 1562 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 33,794 psi | 54% | 2493 fps | 95.2% |
| IMR 3031 | <<locked>> | 80% | 33,504 psi | 54% | 2543 fps | 99.6% |
| IMR 4064 | <<locked>> | 86% | 37,739 psi | 61% | 2572 fps | 95.5% |
| IMR 4166 Enduron | <<locked>> | 96% | 51,648 psi | 83% | 2799 fps | 95.1% |
| IMR 4198 | <<locked>> | 80% | 47,355 psi | 76% | 2674 fps | 100% |
| IMR 4451 Enduron | <<locked>> | 98% | 52,272 psi | 84% | 2838 fps | 95.1% |
| IMR 4895 | <<locked>> | 82% | 36,550 psi | 59% | 2602 fps | 95.8% |
| IMR 8208 XBR | <<locked>> | 80% | 39,697 psi | 64% | 2612 fps | 97.9% |
| Lovex D073.5 | <<locked>> | 80% | 44,179 psi | 71% | 2697 fps | 99.3% |
| Lovex D073.6 | <<locked>> | 80% | 35,708 psi | 57% | 2569 fps | 98.4% |
| Lovex S060 | <<locked>> | 80% | 38,435 psi | 62% | 2543 fps | 96.3% |
| Lovex S062 | <<locked>> | 80% | 33,054 psi | 53% | 2477 fps | 96% |
| Lovex S065 | <<locked>> | 96% | 44,701 psi | 72% | 2720 fps | 95% |
| Norma 200 | <<locked>> | 80% | 52,243 psi | 84% | 2762 fps | 100% |
| Norma 201 | <<locked>> | 80% | 36,680 psi | 59% | 2549 fps | 97.2% |
| Norma 202 | <<locked>> | 80% | 36,854 psi | 59% | 2569 fps | 99.1% |
| Norma 203B | <<locked>> | 82% | 35,085 psi | 56% | 2556 fps | 95.2% |
| Norma URP | <<locked>> | 96% | 39,842 psi | 64% | 2703 fps | 95.1% |
| Ramshot Big Game | <<locked>> | 84% | 37,159 psi | 60% | 2625 fps | 95.6% |
| Ramshot TAC | <<locked>> | 84% | 45,382 psi | 73% | 2720 fps | 95.4% |
| Ramshot Wild Boar | <<locked>> | 80% | 38,653 psi | 62% | 2625 fps | 96.3% |
| Ramshot X-Terminator | <<locked>> | 80% | 42,975 psi | 69% | 2657 fps | 97.3% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 25,556 psi | 41% | 1598 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 44,556 psi | 71% | 2703 fps | 99.6% |
| ReloadSwiss RS 50 | <<locked>> | 92% | 47,805 psi | 77% | 2772 fps | 95% |
| ReloadSwiss RS 52 | 57.4 gr | 82% | 36,941 psi | 59% | 2661 fps | 95.1% |
| ReloadSwiss RS 60 | <<locked>> | 82% | 30,647 psi | 49% | 2516 fps | 96% |
| ReloadSwiss RS 62 | <<locked>> | 98% | 42,235 psi | 68% | 2779 fps | 95.6% |
| Rottweil R 901 | <<locked>> | 80% | 40,335 psi | 65% | 2608 fps | 99.5% |
| Rottweil R 902 | <<locked>> | 80% | 34,809 psi | 56% | 2497 fps | 96.6% |
| Rottweil R 903 | <<locked>> | 84% | 32,387 psi | 52% | 2497 fps | 95% |
| Shooters World Long Rifle | <<locked>> | 96% | 44,701 psi | 72% | 2720 fps | 95% |
| Shooters World Match Rifle | <<locked>> | 80% | 35,708 psi | 57% | 2569 fps | 98.4% |
| Shooters World Precision | <<locked>> | 80% | 33,054 psi | 53% | 2477 fps | 96% |
| Shooters World Tactical Rifle | <<locked>> | 80% | 47,224 psi | 76% | 2720 fps | 99% |
| SNPE Vectan BA6 1/2 | <<locked>> | 80% | 53,330 psi | 86% | 2493 fps | 100% |
| SNPE Vectan SP 10 | <<locked>> | 80% | 50,038 psi | 80% | 2805 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 86% | 36,303 psi | 58% | 2612 fps | 95.4% |
| SNPE Vectan SP 3 | <<locked>> | 80% | 47,282 psi | 76% | 2720 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 84% | 42,946 psi | 69% | 2680 fps | 95.4% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 36,100 psi | 58% | 2556 fps | 95.5% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 38,464 psi | 62% | 2526 fps | 99.3% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 31,488 psi | 50% | 2385 fps | 98.8% |
| Somchem S321 | <<locked>> | 80% | 42,496 psi | 68% | 2690 fps | 98.7% |
| Somchem S335 | <<locked>> | 80% | 37,942 psi | 61% | 2526 fps | 99.7% |
| Somchem S341 | <<locked>> | 80% | 37,188 psi | 60% | 2572 fps | 95.8% |
| Somchem S355 | <<locked>> | 84% | 33,634 psi | 54% | 2513 fps | 95.2% |
| Somchem S365 | <<locked>> | 92% | 31,111 psi | 50% | 2533 fps | 95.4% |
| Unknown powder | <<locked>> | 96% | 43,830 psi | 70% | 2772 fps | 95.5% |
| Vihtavuori N130 | <<locked>> | 80% | 43,729 psi | 70% | 2608 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 38,609 psi | 62% | 2530 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 33,779 psi | 54% | 2500 fps | 99.9% |
| Vihtavuori N140 | <<locked>> | 80% | 34,867 psi | 56% | 2503 fps | 99% |
| Vihtavuori N150 | <<locked>> | 82% | 29,805 psi | 48% | 2395 fps | 95.3% |
| Vihtavuori N160 | <<locked>> | 96% | 42,003 psi | 67% | 2710 fps | 95.6% |
| Vihtavuori N530 | <<locked>> | 80% | 39,581 psi | 63% | 2608 fps | 97.9% |
| Vihtavuori N540 | <<locked>> | 80% | 33,518 psi | 54% | 2487 fps | 98.3% |
| Vihtavuori N550 | <<locked>> | 96% | 41,002 psi | 66% | 2710 fps | 95.2% |
| Winchester 6.5 StaBALL | <<locked>> | 90% | 35,186 psi | 56% | 2530 fps | 95.6% |
| Winchester 748 | <<locked>> | 80% | 41,640 psi | 67% | 2710 fps | 99% |
| Winchester 760 | <<locked>> | 98% | 50,836 psi | 82% | 2907 fps | 95.1% |
| Winchester StaBALL Match | <<locked>> | 80% | 44,266 psi | 71% | 2746 fps | 98.3% |
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 .338 Win Mag. loaded with the .338 | 185gr | Barnes MRX BT. ReloadSwiss RS 60 delivers the highest muzzle velocity at 3,061 fps; across all powders the maximum-charge window runs from 1,749 fps to 3,061 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 (430 MPa), the top charges use 55–90 %, leaving at least 10 % headroom. The 185.0 gr projectile in 0.338" calls for a 1:13.0 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, Hodgdon LEVERevolution rank at the top here: for .338 Win Mag. with the .338 | 185gr | 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.