Load Specifications
Load data in caliber .338 Win Mag. with .338 | 186gr | Peregrine VLR-5 bullet and 94 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 60 and ReloadSwiss RS 52.
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% | 53,403 psi | 86% | 2792 fps | 100% |
| Accurate 2460 | <<locked>> | 86% | 55,376 psi | 89% | 2864 fps | 100% |
| Accurate 2495 | <<locked>> | 94% | 54,099 psi | 87% | 2851 fps | 100% |
| Accurate 2520 | <<locked>> | 90% | 55,390 psi | 89% | 2910 fps | 100% |
| Accurate 2520 | <<locked>> | 90% | 55,390 psi | 89% | 2910 fps | 100% |
| Accurate 4064 | <<locked>> | 96% | 55,245 psi | 89% | 2904 fps | 100% |
| Accurate 4350ᴾ | <<locked>> | 100% | 47,456 psi | 76% | 2851 fps | 97.5% |
| Accurate LT-30 | <<locked>> | 82% | 53,534 psi | 86% | 2743 fps | 100% |
| Accurate LT-32 | <<locked>> | 82% | 53,954 psi | 87% | 2769 fps | 100% |
| ADI AR 2206H | <<locked>> | 90% | 53,548 psi | 86% | 2887 fps | 99.3% |
| ADI AR 2208 | <<locked>> | 96% | 54,520 psi | 87% | 2881 fps | 99% |
| ADI AR 2219 | <<locked>> | 82% | 54,940 psi | 88% | 2871 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 90% | 56,246 psi | 90% | 2897 fps | 99.9% |
| Alliant AR-Comp | <<locked>> | 90% | 56,275 psi | 90% | 2877 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 84% | 53,359 psi | 86% | 2940 fps | 99.6% |
| Alliant Power Pro 2000-MR | <<locked>> | 92% | 52,924 psi | 85% | 2992 fps | 98.8% |
| Alliant Reloder- TS 15.5 | <<locked>> | 96% | 54,012 psi | 87% | 2907 fps | 99.8% |
| Alliant Reloder-10x | <<locked>> | 84% | 54,505 psi | 87% | 2812 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 94% | 54,781 psi | 88% | 2927 fps | 99.1% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 47,021 psi | 75% | 2858 fps | 97.5% |
| Alliant Reloder-17ᴾ | <<locked>> | 100% | 54,447 psi | 87% | 3018 fps | 99.8% |
| Baschieri & Pellagri 106 | <<locked>> | 82% | 53,272 psi | 85% | 2743 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 90% | 53,272 psi | 85% | 2897 fps | 98.5% |
| Bofors RP3 | <<locked>> | 96% | 54,433 psi | 87% | 2920 fps | 99.8% |
| Hodgdon Benchmark | <<locked>> | 88% | 54,955 psi | 88% | 2831 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 90% | 54,128 psi | 87% | 2913 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 88% | 56,347 psi | 90% | 3015 fps | 99.3% |
| Hodgdon H322 | <<locked>> | 88% | 56,246 psi | 90% | 2887 fps | 100% |
| Hodgdon H335 | <<locked>> | 82% | 54,230 psi | 87% | 2867 fps | 100% |
| Hodgdon H380 | <<locked>> | 96% | 55,898 psi | 90% | 2930 fps | 98.4% |
| Hodgdon H4198 | <<locked>> | 82% | 55,927 psi | 90% | 2795 fps | 100% |
| Hodgdon H4895 | <<locked>> | 90% | 54,027 psi | 87% | 2900 fps | 99.6% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 43,004 psi | 69% | 2736 fps | 98.1% |
| Hodgdon LEVERevolution | <<locked>> | 96% | 55,390 psi | 89% | 2972 fps | 99.9% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 34,708 psi | 56% | 1749 fps | 100% |
| Hodgdon VARGET | <<locked>> | 94% | 53,461 psi | 86% | 2874 fps | 99.5% |
| IMR 3031 | <<locked>> | 94% | 55,100 psi | 88% | 2917 fps | 100% |
| IMR 4064 | <<locked>> | 98% | 56,420 psi | 90% | 2904 fps | 99.3% |
| IMR 4198 | <<locked>> | 84% | 54,810 psi | 88% | 2772 fps | 100% |
| IMR 4895 | <<locked>> | 94% | 56,217 psi | 90% | 2959 fps | 99.6% |
| IMR 8208 XBR | <<locked>> | 90% | 56,246 psi | 90% | 2897 fps | 99.9% |
| Lovex D073.5 | <<locked>> | 84% | 52,895 psi | 85% | 2831 fps | 100% |
| Lovex D073.6 | <<locked>> | 92% | 56,333 psi | 90% | 2917 fps | 100% |
| Lovex S060 | <<locked>> | 90% | 53,708 psi | 86% | 2818 fps | 99.3% |
| Lovex S062 | <<locked>> | 94% | 53,476 psi | 86% | 2864 fps | 99.8% |
| Lovex S065ᴾ | <<locked>> | 100% | 52,576 psi | 84% | 2848 fps | 97% |
| Norma 201 | <<locked>> | 92% | 55,637 psi | 89% | 2887 fps | 99.9% |
| Norma 202 | <<locked>> | 92% | 56,217 psi | 90% | 2894 fps | 100% |
| Norma 203B | <<locked>> | 94% | 53,925 psi | 86% | 2913 fps | 99.4% |
| Norma URPᴾ | <<locked>> | 100% | 47,210 psi | 76% | 2844 fps | 97.3% |
| Ramshot Big Game | <<locked>> | 94% | 54,389 psi | 87% | 2940 fps | 99.3% |
| Ramshot TAC | <<locked>> | 88% | 53,432 psi | 86% | 2854 fps | 97.4% |
| Ramshot Wild Boar | <<locked>> | 90% | 55,999 psi | 90% | 2927 fps | 99.5% |
| Ramshot X-Terminator | <<locked>> | 86% | 54,273 psi | 87% | 2848 fps | 99.2% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 35,143 psi | 56% | 1795 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 86% | 55,956 psi | 90% | 2881 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 94% | 52,982 psi | 85% | 2854 fps | 96.3% |
| ReloadSwiss RS 52 | <<locked>> | 92% | 54,853 psi | 88% | 2992 fps | 99.1% |
| ReloadSwiss RS 60 | <<locked>> | 98% | 54,447 psi | 87% | 3025 fps | 100% |
| ReloadSwiss RS 62ᴾ | <<locked>> | 100% | 47,253 psi | 76% | 2871 fps | 97.1% |
| ReloadSwiss RS 70ᴾ | <<locked>> | 100% | 48,370 psi | 78% | 2890 fps | 96.5% |
| Rottweil R 901 | <<locked>> | 88% | 53,330 psi | 86% | 2825 fps | 100% |
| Rottweil R 902 | <<locked>> | 94% | 56,159 psi | 90% | 2884 fps | 99.9% |
| Rottweil R 903 | <<locked>> | 98% | 53,998 psi | 87% | 2907 fps | 99.7% |
| Shooters World Long Rifleᴾ | <<locked>> | 100% | 52,576 psi | 84% | 2848 fps | 97% |
| Shooters World Match Rifle | <<locked>> | 92% | 56,333 psi | 90% | 2917 fps | 100% |
| Shooters World Precision | <<locked>> | 94% | 53,476 psi | 86% | 2864 fps | 99.8% |
| Shooters World Tactical Rifle | <<locked>> | 84% | 56,043 psi | 90% | 2854 fps | 99.8% |
| SNPE Vectan SP 10 | <<locked>> | 82% | 55,259 psi | 89% | 2877 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 98% | 55,970 psi | 90% | 2969 fps | 99.5% |
| SNPE Vectan SP 3 | <<locked>> | 84% | 54,563 psi | 87% | 2825 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 90% | 54,998 psi | 88% | 2884 fps | 98.1% |
| SNPE Vectan SP 9 | <<locked>> | 92% | 55,579 psi | 89% | 2910 fps | 99.5% |
| SNPE Vectan Tubal 3000 | <<locked>> | 90% | 54,520 psi | 87% | 2789 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 96% | 54,244 psi | 87% | 2782 fps | 100% |
| Somchem S321 | <<locked>> | 86% | 54,157 psi | 87% | 2881 fps | 99.9% |
| Somchem S335 | <<locked>> | 90% | 53,563 psi | 86% | 2785 fps | 100% |
| Somchem S341 | <<locked>> | 90% | 54,404 psi | 87% | 2877 fps | 99.3% |
| Somchem S355 | <<locked>> | 98% | 54,433 psi | 87% | 2904 fps | 99.6% |
| Somchem S365ᴾ | <<locked>> | 100% | 42,076 psi | 67% | 2789 fps | 99.1% |
| Unknown powderᴾ | <<locked>> | 100% | 51,953 psi | 83% | 2910 fps | 97.6% |
| Vihtavuori N120 | <<locked>> | 82% | 55,187 psi | 88% | 2707 fps | 100% |
| Vihtavuori N130 | <<locked>> | 88% | 56,362 psi | 90% | 2789 fps | 100% |
| Vihtavuori N133 | <<locked>> | 92% | 53,505 psi | 86% | 2766 fps | 100% |
| Vihtavuori N135 | <<locked>> | 94% | 54,288 psi | 87% | 2844 fps | 100% |
| Vihtavuori N140 | <<locked>> | 94% | 55,782 psi | 89% | 2861 fps | 100% |
| Vihtavuori N150ᴾ | <<locked>> | 100% | 49,124 psi | 79% | 2789 fps | 99.7% |
| Vihtavuori N160ᴾ | <<locked>> | 100% | 52,533 psi | 84% | 2884 fps | 98.1% |
| Vihtavuori N530 | <<locked>> | 88% | 56,231 psi | 90% | 2907 fps | 100% |
| Vihtavuori N540 | <<locked>> | 94% | 55,608 psi | 89% | 2890 fps | 100% |
| Vihtavuori N550ᴾ | <<locked>> | 100% | 52,678 psi | 84% | 2933 fps | 98.2% |
| Winchester 6.5 StaBALLᴾ | <<locked>> | 100% | 51,039 psi | 82% | 2835 fps | 99.4% |
| Winchester 748 | <<locked>> | 86% | 53,461 psi | 86% | 2904 fps | 100% |
| Winchester StaBALL Match | <<locked>> | 84% | 53,127 psi | 85% | 2890 fps | 99.6% |
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% | 41,510 psi | 67% | 2605 fps | 100% |
| Accurate 2460 | <<locked>> | 80% | 45,121 psi | 72% | 2703 fps | 99.9% |
| Accurate 2495 | <<locked>> | 80% | 33,605 psi | 54% | 2500 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 38,798 psi | 62% | 2631 fps | 99.1% |
| Accurate 2520 | <<locked>> | 80% | 38,798 psi | 62% | 2631 fps | 99.1% |
| Accurate 4064 | <<locked>> | 80% | 33,112 psi | 53% | 2503 fps | 98.8% |
| Accurate 4350 | <<locked>> | 94% | 38,435 psi | 62% | 2677 fps | 95% |
| Accurate LT-30 | <<locked>> | 80% | 50,125 psi | 80% | 2694 fps | 100% |
| Accurate LT-32 | <<locked>> | 80% | 50,517 psi | 81% | 2717 fps | 100% |
| ADI AR 2206H | <<locked>> | 80% | 39,146 psi | 63% | 2618 fps | 96.6% |
| ADI AR 2208 | <<locked>> | 84% | 37,710 psi | 60% | 2569 fps | 95.4% |
| ADI AR 2219 | <<locked>> | 80% | 51,387 psi | 82% | 2818 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 80% | 41,191 psi | 66% | 2638 fps | 98.3% |
| Alliant AR-Comp | <<locked>> | 80% | 40,321 psi | 65% | 2641 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 80% | 46,731 psi | 75% | 2825 fps | 98.9% |
| Alliant Power Pro 2000-MR | 61.4 gr | 84% | 40,408 psi | 65% | 2743 fps | 95.8% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 32,430 psi | 52% | 2484 fps | 95.4% |
| Alliant Reloder-10x | <<locked>> | 80% | 48,196 psi | 77% | 2720 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 82% | 37,246 psi | 60% | 2598 fps | 95.4% |
| Alliant Reloder-16 | <<locked>> | 94% | 39,146 psi | 63% | 2690 fps | 95.1% |
| Alliant Reloder-17 | <<locked>> | 86% | 34,214 psi | 55% | 2598 fps | 95.1% |
| Baschieri & Pellagri 106 | <<locked>> | 80% | 49,908 psi | 80% | 2694 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 82% | 40,654 psi | 65% | 2667 fps | 95.8% |
| Bofors RP3 | <<locked>> | 80% | 31,720 psi | 51% | 2477 fps | 95.3% |
| Hodgdon Benchmark | <<locked>> | 80% | 43,062 psi | 69% | 2631 fps | 99.1% |
| Hodgdon BL-C2 | <<locked>> | 80% | 38,261 psi | 61% | 2631 fps | 98.2% |
| Hodgdon CFE223 | <<locked>> | 80% | 42,206 psi | 68% | 2766 fps | 96.9% |
| Hodgdon H322 | <<locked>> | 80% | 43,584 psi | 70% | 2687 fps | 100% |
| Hodgdon H335 | <<locked>> | 80% | 50,575 psi | 81% | 2815 fps | 100% |
| Hodgdon H380 | <<locked>> | 88% | 42,902 psi | 69% | 2703 fps | 95.7% |
| Hodgdon H4198 | <<locked>> | 80% | 52,634 psi | 84% | 2746 fps | 100% |
| Hodgdon H4895 | <<locked>> | 80% | 39,436 psi | 63% | 2631 fps | 97.3% |
| Hodgdon Hybrid 100V | <<locked>> | 92% | 33,475 psi | 54% | 2523 fps | 95% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 32,460 psi | 52% | 2523 fps | 95.4% |
| Hodgdon TrailBoss | <<locked>> | 80% | 25,788 psi | 41% | 1565 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 34,360 psi | 55% | 2507 fps | 95.6% |
| IMR 3031 | <<locked>> | 80% | 35,128 psi | 56% | 2569 fps | 99.8% |
| IMR 4064 | <<locked>> | 84% | 36,840 psi | 59% | 2546 fps | 95.4% |
| IMR 4198 | <<locked>> | 80% | 48,646 psi | 78% | 2684 fps | 100% |
| IMR 4895 | <<locked>> | 80% | 35,824 psi | 57% | 2575 fps | 95.7% |
| IMR 8208 XBR | <<locked>> | 80% | 41,191 psi | 66% | 2638 fps | 98.3% |
| Lovex D073.5 | <<locked>> | 80% | 46,166 psi | 74% | 2723 fps | 99.6% |
| Lovex D073.6 | <<locked>> | 80% | 37,434 psi | 60% | 2595 fps | 98.9% |
| Lovex S060 | <<locked>> | 80% | 39,784 psi | 64% | 2566 fps | 96.9% |
| Lovex S062 | <<locked>> | 80% | 34,635 psi | 56% | 2507 fps | 96.7% |
| Lovex S065 | <<locked>> | 96% | 46,485 psi | 75% | 2743 fps | 95.7% |
| Norma 201 | <<locked>> | 80% | 38,348 psi | 61% | 2575 fps | 97.8% |
| Norma 202 | <<locked>> | 80% | 38,421 psi | 62% | 2592 fps | 99.4% |
| Norma 203B | <<locked>> | 80% | 34,418 psi | 55% | 2533 fps | 95.1% |
| Norma URP | <<locked>> | 94% | 39,044 psi | 63% | 2680 fps | 95% |
| Ramshot Big Game | <<locked>> | 82% | 36,187 psi | 58% | 2595 fps | 95.4% |
| Ramshot TAC | <<locked>> | 82% | 43,787 psi | 70% | 2684 fps | 95.1% |
| Ramshot Wild Boar | <<locked>> | 80% | 40,118 psi | 64% | 2648 fps | 96.9% |
| Ramshot X-Terminator | <<locked>> | 80% | 44,585 psi | 71% | 2684 fps | 97.8% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 25,918 psi | 42% | 1598 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 46,050 psi | 74% | 2726 fps | 99.8% |
| ReloadSwiss RS 50 | <<locked>> | 92% | 49,501 psi | 79% | 2795 fps | 95.6% |
| ReloadSwiss RS 52 | 58.1 gr | 82% | 38,696 psi | 62% | 2694 fps | 95.9% |
| ReloadSwiss RS 60 | 57.5 gr | 80% | 29,805 psi | 48% | 2484 fps | 95.7% |
| ReloadSwiss RS 62 | <<locked>> | 96% | 41,162 psi | 66% | 2753 fps | 95.4% |
| ReloadSwiss RS 70 | <<locked>> | 98% | 45,121 psi | 72% | 2825 fps | 95.5% |
| Rottweil R 901 | <<locked>> | 80% | 42,003 psi | 67% | 2631 fps | 99.7% |
| Rottweil R 902 | <<locked>> | 80% | 36,448 psi | 58% | 2526 fps | 97.2% |
| Rottweil R 903 | <<locked>> | 84% | 34,055 psi | 55% | 2530 fps | 95.8% |
| Shooters World Long Rifle | <<locked>> | 96% | 46,485 psi | 75% | 2743 fps | 95.7% |
| Shooters World Match Rifle | <<locked>> | 80% | 37,434 psi | 60% | 2595 fps | 98.9% |
| Shooters World Precision | <<locked>> | 80% | 34,635 psi | 56% | 2507 fps | 96.7% |
| Shooters World Tactical Rifle | <<locked>> | 80% | 48,733 psi | 78% | 2743 fps | 99.2% |
| SNPE Vectan SP 10 | <<locked>> | 80% | 51,576 psi | 83% | 2825 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 84% | 35,375 psi | 57% | 2579 fps | 95.2% |
| SNPE Vectan SP 3 | <<locked>> | 80% | 48,051 psi | 77% | 2730 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 82% | 41,713 psi | 67% | 2651 fps | 95.2% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 37,695 psi | 60% | 2585 fps | 96.2% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 39,958 psi | 64% | 2546 fps | 99.6% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 32,851 psi | 53% | 2408 fps | 99.1% |
| Somchem S321 | <<locked>> | 80% | 44,063 psi | 71% | 2710 fps | 99.1% |
| Somchem S335 | <<locked>> | 80% | 39,465 psi | 63% | 2549 fps | 99.8% |
| Somchem S341 | <<locked>> | 80% | 38,638 psi | 62% | 2595 fps | 96.4% |
| Somchem S355 | <<locked>> | 82% | 32,924 psi | 53% | 2487 fps | 95.1% |
| Somchem S365 | <<locked>> | 90% | 30,574 psi | 49% | 2510 fps | 95.4% |
| Unknown powder | <<locked>> | 94% | 42,801 psi | 69% | 2743 fps | 95.4% |
| Vihtavuori N120 | <<locked>> | 80% | 52,156 psi | 84% | 2664 fps | 100% |
| Vihtavuori N130 | <<locked>> | 80% | 44,440 psi | 71% | 2612 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 37,492 psi | 60% | 2503 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 34,418 psi | 55% | 2510 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 35,795 psi | 57% | 2520 fps | 99.3% |
| Vihtavuori N150 | <<locked>> | 84% | 29,921 psi | 48% | 2392 fps | 95.5% |
| Vihtavuori N160 | <<locked>> | 92% | 40,234 psi | 65% | 2664 fps | 95.2% |
| Vihtavuori N530 | <<locked>> | 80% | 43,221 psi | 69% | 2687 fps | 98.8% |
| Vihtavuori N540 | <<locked>> | 80% | 35,505 psi | 57% | 2533 fps | 98.9% |
| Vihtavuori N550 | <<locked>> | 92% | 40,466 psi | 65% | 2707 fps | 95.3% |
| Winchester 6.5 StaBALL | <<locked>> | 88% | 34,185 psi | 55% | 2500 fps | 95.3% |
| Winchester 748 | <<locked>> | 80% | 43,178 psi | 69% | 2730 fps | 99.3% |
| Winchester StaBALL Match | <<locked>> | 80% | 46,006 psi | 74% | 2769 fps | 98.7% |
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 113 powders for .338 Win Mag. loaded with the .338 | 186gr | Peregrine VLR-5. ReloadSwiss RS 60 delivers the highest muzzle velocity at 3,025 fps; across all powders the maximum-charge window runs from 1,749 fps to 3,025 fps. Accurate 4350 gives the best case fill at 100 %, and 113 of the 113 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (430 MPa), the top charges use 53–90 %, leaving at least 10 % headroom. The 186.0 gr projectile in 0.338" calls for a 1:13.5 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 60, ReloadSwiss RS 52 rank at the top here: for .338 Win Mag. with the .338 | 186gr | Peregrine VLR-5 they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, Alliant Reloder-23, Alliant Reloder-26, Hodgdon H4350 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.