Load Specifications
Load data in caliber .338 Lapua Mag. Ackley Improved with .338 | 270gr | Peregrine VLR-4 bullet and 79 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Hodgdon Retumbo, ReloadSwiss RS 76 and Vihtavuori N560.
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: 27"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2700 | <<locked>> | 82% | 62,584 psi | 90% | 2713 fps | 100% |
| Accurate 3100 | <<locked>> | 92% | 59,973 psi | 86% | 2733 fps | 100% |
| Accurate 4350 | <<locked>> | 84% | 60,945 psi | 88% | 2749 fps | 100% |
| Accurate MAGPRO | <<locked>> | 92% | 60,031 psi | 86% | 2867 fps | 99.9% |
| ADI APS 450 | <<locked>> | 82% | 61,250 psi | 88% | 2106 fps | 100% |
| ADI AR 2209 | <<locked>> | 90% | 62,091 psi | 89% | 2828 fps | 100% |
| ADI AR 2213 | <<locked>> | 92% | 60,162 psi | 86% | 2851 fps | 100% |
| ADI AR 2217ᴾ | <<locked>> | 100% | 58,175 psi | 84% | 2822 fps | 100% |
| ADI AR 2218ᴾ | <<locked>> | 100% | 50,444 psi | 72% | 2822 fps | 98.5% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 52,518 psi | 75% | 2789 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 86% | 62,236 psi | 89% | 2799 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 90% | 61,366 psi | 88% | 2818 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 92% | 60,234 psi | 87% | 2838 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 94% | 62,018 psi | 89% | 2785 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 98% | 62,192 psi | 89% | 2861 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 88% | 58,972 psi | 85% | 2835 fps | 100% |
| Alliant Reloder-33ᴾ | <<locked>> | 100% | 55,477 psi | 80% | 2867 fps | 99.1% |
| Alliant Reloder-50ᴾ | <<locked>> | 100% | 46,456 psi | 67% | 2720 fps | 97.1% |
| Baschieri & Pellagri 109 | <<locked>> | 94% | 60,597 psi | 87% | 2815 fps | 99.5% |
| Bofors RP15 | <<locked>> | 94% | 59,350 psi | 85% | 2828 fps | 100% |
| Bofors RP30ᴾ | <<locked>> | 100% | 61,786 psi | 89% | 2887 fps | 100% |
| Bofors RP5 | <<locked>> | 92% | 60,234 psi | 87% | 2838 fps | 100% |
| Bofors RP7 | <<locked>> | 84% | 62,062 psi | 89% | 2749 fps | 100% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 59,886 psi | 86% | 2841 fps | 100% |
| Hodgdon H4350 | <<locked>> | 84% | 59,364 psi | 85% | 2749 fps | 100% |
| Hodgdon H4831 | <<locked>> | 96% | 62,845 psi | 90% | 2828 fps | 100% |
| Hodgdon H4831 SC | <<locked>> | 92% | 62,236 psi | 89% | 2822 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 88% | 62,163 psi | 89% | 2720 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 98% | 61,322 psi | 88% | 2959 fps | 100% |
| Hodgdon Superformance | <<locked>> | 82% | 59,451 psi | 85% | 2802 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,550 psi | 54% | 1693 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 82% | 61,090 psi | 88% | 2713 fps | 100% |
| IMR 4350 | <<locked>> | 86% | 60,481 psi | 87% | 2743 fps | 100% |
| IMR 4451 Enduron | <<locked>> | 82% | 59,654 psi | 86% | 2720 fps | 100% |
| IMR 4831 | <<locked>> | 90% | 62,555 psi | 90% | 2756 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 90% | 59,799 psi | 86% | 2762 fps | 100% |
| IMR 7828 SSC | <<locked>> | 92% | 62,787 psi | 90% | 2890 fps | 100% |
| IMR 7977 Enduron | <<locked>> | 98% | 62,004 psi | 89% | 2762 fps | 97.2% |
| IMR 8133 Enduronᴾ | <<locked>> | 100% | 47,834 psi | 69% | 2713 fps | 99.8% |
| Lovex S065 | <<locked>> | 84% | 60,568 psi | 87% | 2713 fps | 100% |
| Lovex S070 | <<locked>> | 86% | 62,830 psi | 90% | 2769 fps | 100% |
| Lovex S071 | <<locked>> | 98% | 61,380 psi | 88% | 2753 fps | 100% |
| Norma 204 | <<locked>> | 86% | 62,265 psi | 89% | 2812 fps | 100% |
| Norma 217ᴾ | <<locked>> | 100% | 48,631 psi | 70% | 2736 fps | 100% |
| Norma MRP | <<locked>> | 90% | 60,597 psi | 87% | 2858 fps | 100% |
| Norma URP | <<locked>> | 86% | 62,961 psi | 90% | 2782 fps | 100% |
| Ramshot Grand | <<locked>> | 88% | 58,711 psi | 84% | 2841 fps | 100% |
| Ramshot Hunter | <<locked>> | 86% | 61,931 psi | 89% | 2799 fps | 100% |
| Ramshot Magnum | <<locked>> | 92% | 59,930 psi | 86% | 2808 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 38,508 psi | 55% | 1732 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 84% | 61,279 psi | 88% | 2779 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 84% | 59,886 psi | 86% | 2808 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 98% | 62,526 psi | 90% | 2953 fps | 100% |
| ReloadSwiss RS 80ᴾ | <<locked>> | 100% | 61,554 psi | 88% | 2930 fps | 100% |
| Rottweil R 904 | <<locked>> | 90% | 62,584 psi | 90% | 2795 fps | 100% |
| Rottweil R 905 | <<locked>> | 90% | 61,090 psi | 88% | 2808 fps | 100% |
| Rottweil R 907 | <<locked>> | 84% | 62,062 psi | 89% | 2749 fps | 100% |
| Shooters World Long Rifle | <<locked>> | 84% | 60,568 psi | 87% | 2713 fps | 100% |
| Shooters World SW4350 | <<locked>> | 86% | 62,830 psi | 90% | 2769 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 82% | 62,613 psi | 90% | 2585 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 84% | 59,712 psi | 86% | 2677 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 90% | 60,655 psi | 87% | 2805 fps | 100% |
| Somchem S361 | <<locked>> | 88% | 60,220 psi | 87% | 2743 fps | 100% |
| Somchem S365 | <<locked>> | 86% | 60,278 psi | 87% | 2733 fps | 100% |
| Somchem S385 | <<locked>> | 90% | 61,337 psi | 88% | 2776 fps | 100% |
| Unknown powder | <<locked>> | 84% | 62,990 psi | 90% | 2782 fps | 100% |
| Vihtavuori N150 | <<locked>> | 86% | 61,656 psi | 89% | 2657 fps | 100% |
| Vihtavuori N160 | <<locked>> | 82% | 59,321 psi | 85% | 2700 fps | 100% |
| Vihtavuori N165 | <<locked>> | 94% | 59,146 psi | 85% | 2736 fps | 100% |
| Vihtavuori N170ᴾ | <<locked>> | 100% | 53,650 psi | 77% | 2707 fps | 97.4% |
| Vihtavuori N550 | <<locked>> | 82% | 59,857 psi | 86% | 2749 fps | 100% |
| Vihtavuori N555 | <<locked>> | 90% | 60,060 psi | 86% | 2762 fps | 100% |
| Vihtavuori N560 | <<locked>> | 92% | 60,684 psi | 87% | 2877 fps | 100% |
| Vihtavuori N565 | <<locked>> | 96% | 60,220 psi | 87% | 2851 fps | 100% |
| Vihtavuori N568ᴾ | <<locked>> | 100% | 61,888 psi | 89% | 2923 fps | 100% |
| Vihtavuori N570ᴾ | <<locked>> | 100% | 59,524 psi | 86% | 2936 fps | 99.3% |
| Winchester 6.5 StaBALL | <<locked>> | 84% | 60,278 psi | 87% | 2677 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 94% | 62,250 psi | 89% | 2881 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 88% | 58,798 psi | 84% | 2746 fps | 100% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 27"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2700 | <<locked>> | 80% | 58,479 psi | 84% | 2661 fps | 100% |
| Accurate 3100 | <<locked>> | 80% | 39,914 psi | 57% | 2441 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 53,142 psi | 76% | 2651 fps | 100% |
| Accurate MAGPRO | <<locked>> | 80% | 39,131 psi | 56% | 2516 fps | 96.6% |
| ADI APS 450 | <<locked>> | 80% | 59,350 psi | 85% | 2083 fps | 100% |
| ADI AR 2209 | <<locked>> | 80% | 44,411 psi | 64% | 2569 fps | 99.7% |
| ADI AR 2213 | <<locked>> | 80% | 39,624 psi | 57% | 2516 fps | 98.4% |
| ADI AR 2217 | <<locked>> | 82% | 31,357 psi | 45% | 2329 fps | 96% |
| ADI AR 2218 | <<locked>> | 94% | 40,524 psi | 58% | 2621 fps | 95.5% |
| ADI AR 2225 | <<locked>> | 80% | 26,600 psi | 38% | 2244 fps | 96.9% |
| Alliant Reloder-16 | <<locked>> | 80% | 51,213 psi | 74% | 2657 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 44,280 psi | 64% | 2562 fps | 99.7% |
| Alliant Reloder-22 | <<locked>> | 80% | 40,190 psi | 58% | 2523 fps | 99.3% |
| Alliant Reloder-23 | <<locked>> | 80% | 38,885 psi | 56% | 2461 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 33,547 psi | 48% | 2411 fps | 99.9% |
| Alliant Reloder-26 | <<locked>> | 80% | 43,569 psi | 63% | 2618 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 92% | 41,002 psi | 59% | 2618 fps | 96% |
| Alliant Reloder-50 | <<locked>> | 96% | 39,871 psi | 57% | 2595 fps | 95.1% |
| Baschieri & Pellagri 109 | <<locked>> | 80% | 38,856 psi | 56% | 2441 fps | 95.2% |
| Bofors RP15 | <<locked>> | 80% | 37,318 psi | 54% | 2461 fps | 98.7% |
| Bofors RP30 | <<locked>> | 80% | 30,879 psi | 44% | 2343 fps | 96.1% |
| Bofors RP5 | <<locked>> | 80% | 40,190 psi | 58% | 2523 fps | 99.3% |
| Bofors RP7 | <<locked>> | 80% | 54,708 psi | 79% | 2651 fps | 100% |
| Hodgdon H1000 | <<locked>> | 80% | 30,066 psi | 43% | 2297 fps | 96% |
| Hodgdon H4350 | <<locked>> | 80% | 52,344 psi | 75% | 2654 fps | 100% |
| Hodgdon H4831 | <<locked>> | 80% | 37,246 psi | 54% | 2415 fps | 97.1% |
| Hodgdon H4831 SC | <<locked>> | 80% | 41,495 psi | 60% | 2500 fps | 98.2% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 47,921 psi | 69% | 2539 fps | 100% |
| Hodgdon Retumbo | 81.8 gr | 80% | 32,634 psi | 47% | 2448 fps | 98.4% |
| Hodgdon Superformance | <<locked>> | 80% | 55,361 psi | 80% | 2749 fps | 100% |
| Hodgdon TrailBoss | <<locked>> | 80% | 28,094 psi | 40% | 1509 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 80% | 57,580 psi | 83% | 2667 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 50,154 psi | 72% | 2602 fps | 100% |
| IMR 4451 Enduron | <<locked>> | 80% | 56,072 psi | 81% | 2671 fps | 100% |
| IMR 4831 | <<locked>> | 80% | 45,759 psi | 66% | 2530 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 43,569 psi | 63% | 2507 fps | 98.7% |
| IMR 7828 SSC | <<locked>> | 80% | 40,828 psi | 59% | 2549 fps | 98.7% |
| IMR 7977 Enduron | <<locked>> | 92% | 51,155 psi | 73% | 2605 fps | 95.1% |
| IMR 8133 Enduron | <<locked>> | 86% | 29,559 psi | 42% | 2329 fps | 95.3% |
| Lovex S065 | <<locked>> | 80% | 53,505 psi | 77% | 2621 fps | 100% |
| Lovex S070 | <<locked>> | 80% | 51,924 psi | 75% | 2625 fps | 100% |
| Lovex S071 | <<locked>> | 80% | 34,345 psi | 49% | 2329 fps | 99.6% |
| Norma 204 | <<locked>> | 80% | 50,807 psi | 73% | 2654 fps | 100% |
| Norma 217 | <<locked>> | 82% | 25,831 psi | 37% | 2241 fps | 95.7% |
| Norma MRP | <<locked>> | 80% | 42,409 psi | 61% | 2585 fps | 100% |
| Norma URP | <<locked>> | 80% | 51,764 psi | 74% | 2638 fps | 100% |
| Ramshot Grand | <<locked>> | 80% | 42,902 psi | 62% | 2602 fps | 99.3% |
| Ramshot Hunter | <<locked>> | 80% | 50,763 psi | 73% | 2651 fps | 100% |
| Ramshot Magnum | <<locked>> | 80% | 37,492 psi | 54% | 2467 fps | 99.4% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,877 psi | 41% | 1549 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 53,359 psi | 77% | 2677 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 51,895 psi | 75% | 2703 fps | 100% |
| ReloadSwiss RS 76 | 87.6 gr | 80% | 31,662 psi | 45% | 2421 fps | 99% |
| ReloadSwiss RS 80 | <<locked>> | 84% | 33,214 psi | 48% | 2438 fps | 95.4% |
| Rottweil R 904 | <<locked>> | 80% | 45,426 psi | 65% | 2543 fps | 99.3% |
| Rottweil R 905 | <<locked>> | 80% | 43,772 psi | 63% | 2552 fps | 99.7% |
| Rottweil R 907 | <<locked>> | 80% | 54,708 psi | 79% | 2651 fps | 100% |
| Shooters World Long Rifle | <<locked>> | 80% | 53,505 psi | 77% | 2621 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 51,924 psi | 75% | 2625 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 58,987 psi | 85% | 2546 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 52,373 psi | 75% | 2579 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 43,424 psi | 62% | 2546 fps | 99.7% |
| Somchem S361 | <<locked>> | 80% | 46,079 psi | 66% | 2533 fps | 98.9% |
| Somchem S365 | <<locked>> | 80% | 49,400 psi | 71% | 2595 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 44,121 psi | 63% | 2526 fps | 99.9% |
| Unknown powder | <<locked>> | 80% | 55,230 psi | 79% | 2687 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 51,256 psi | 74% | 2530 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 55,448 psi | 80% | 2654 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 37,304 psi | 54% | 2392 fps | 99.1% |
| Vihtavuori N170 | <<locked>> | 94% | 44,251 psi | 64% | 2549 fps | 95.1% |
| Vihtavuori N550 | <<locked>> | 80% | 56,028 psi | 80% | 2700 fps | 100% |
| Vihtavuori N555 | <<locked>> | 80% | 43,250 psi | 62% | 2530 fps | 100% |
| Vihtavuori N560 | 83.2 gr | 80% | 40,335 psi | 58% | 2546 fps | 98.1% |
| Vihtavuori N565 | <<locked>> | 80% | 34,722 psi | 50% | 2411 fps | 96.8% |
| Vihtavuori N568 | <<locked>> | 84% | 34,795 psi | 50% | 2457 fps | 95.4% |
| Vihtavuori N570 | <<locked>> | 90% | 41,278 psi | 59% | 2628 fps | 95.7% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 52,518 psi | 75% | 2582 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 80% | 36,332 psi | 52% | 2516 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 44,164 psi | 63% | 2530 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 86 powders for .338 Lapua Mag. Ackley Improved loaded with the .338 | 270gr | Peregrine VLR-4. Hodgdon Retumbo delivers the highest muzzle velocity at 2,959 fps; across all powders the maximum-charge window runs from 1,693 fps to 2,959 fps. Accurate 8700 gives the best case fill at 100 %, and 86 of the 86 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (480 MPa), the top charges use 54–90 %, leaving at least 10 % headroom. The 270.0 gr projectile in 0.338" calls for a 1:9.5 twist; slower twists will usually not stabilise this weight. Accurate 8700, ADI AR 2217, ADI AR 2218 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. Hodgdon Retumbo, ReloadSwiss RS 76, Vihtavuori N560 rank at the top here: for .338 Lapua Mag. Ackley Improved with the .338 | 270gr | Peregrine VLR-4 they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, Accurate 8700, Ramshot LRT, SNPE Vectan SP 13 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.