Load Specifications
Load data in caliber .338 Lapua Mag. Ackley Improved with .338 | 275gr | CutEdge LZR bullet and 82 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% | 61,989 psi | 89% | 2674 fps | 100% |
| Accurate 3100 | <<locked>> | 92% | 59,350 psi | 85% | 2697 fps | 100% |
| Accurate 4350 | <<locked>> | 84% | 60,365 psi | 87% | 2713 fps | 100% |
| Accurate MAGPRO | <<locked>> | 92% | 59,393 psi | 85% | 2828 fps | 99.8% |
| ADI APS 450 | <<locked>> | 82% | 61,279 psi | 88% | 2080 fps | 100% |
| ADI AR 2209 | <<locked>> | 90% | 61,351 psi | 88% | 2789 fps | 100% |
| ADI AR 2213 | <<locked>> | 92% | 59,538 psi | 86% | 2812 fps | 100% |
| ADI AR 2217ᴾ | <<locked>> | 100% | 57,580 psi | 83% | 2785 fps | 100% |
| ADI AR 2218ᴾ | <<locked>> | 100% | 49,676 psi | 71% | 2779 fps | 98.3% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 51,808 psi | 74% | 2753 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 90% | 61,438 psi | 88% | 2785 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 86% | 61,641 psi | 89% | 2762 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 90% | 60,684 psi | 87% | 2779 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 92% | 59,654 psi | 86% | 2802 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 94% | 61,337 psi | 88% | 2746 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 98% | 61,279 psi | 88% | 2822 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 90% | 62,540 psi | 90% | 2848 fps | 100% |
| Alliant Reloder-33ᴾ | <<locked>> | 100% | 54,636 psi | 78% | 2828 fps | 99% |
| Alliant Reloder-50ᴾ | <<locked>> | 100% | 45,658 psi | 66% | 2684 fps | 97% |
| Baschieri & Pellagri 109 | <<locked>> | 94% | 60,162 psi | 86% | 2779 fps | 99.5% |
| Bofors RP15 | <<locked>> | 96% | 62,540 psi | 90% | 2838 fps | 100% |
| Bofors RP30ᴾ | <<locked>> | 100% | 60,756 psi | 87% | 2844 fps | 100% |
| Bofors RP5 | <<locked>> | 92% | 59,654 psi | 86% | 2802 fps | 100% |
| Bofors RP7 | <<locked>> | 84% | 61,540 psi | 88% | 2713 fps | 100% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 59,277 psi | 85% | 2802 fps | 100% |
| Hodgdon H4350 | <<locked>> | 86% | 62,714 psi | 90% | 2759 fps | 100% |
| Hodgdon H4831 | <<locked>> | 96% | 62,323 psi | 90% | 2792 fps | 100% |
| Hodgdon H4831 SC | <<locked>> | 92% | 61,699 psi | 89% | 2785 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 88% | 61,656 psi | 89% | 2680 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 98% | 60,394 psi | 87% | 2917 fps | 100% |
| Hodgdon Superformance | <<locked>> | 82% | 58,827 psi | 85% | 2766 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,536 psi | 54% | 1667 fps | 100% |
| IMR 4064 | <<locked>> | 82% | 62,540 psi | 90% | 2674 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 82% | 60,640 psi | 87% | 2677 fps | 100% |
| IMR 4350 | <<locked>> | 86% | 60,089 psi | 86% | 2707 fps | 100% |
| IMR 4451 Enduron | <<locked>> | 82% | 59,292 psi | 85% | 2684 fps | 100% |
| IMR 4831 | <<locked>> | 90% | 61,931 psi | 89% | 2720 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 90% | 59,205 psi | 85% | 2723 fps | 100% |
| IMR 7828 SSC | <<locked>> | 92% | 62,004 psi | 89% | 2851 fps | 100% |
| IMR 7977 Enduron | <<locked>> | 98% | 61,496 psi | 88% | 2726 fps | 97.2% |
| IMR 8133 Enduronᴾ | <<locked>> | 100% | 47,253 psi | 68% | 2677 fps | 99.8% |
| Lovex S065 | <<locked>> | 84% | 60,060 psi | 86% | 2677 fps | 100% |
| Lovex S070 | <<locked>> | 86% | 62,207 psi | 89% | 2730 fps | 100% |
| Lovex S071 | <<locked>> | 98% | 60,771 psi | 87% | 2713 fps | 100% |
| Norma 204 | <<locked>> | 86% | 61,554 psi | 88% | 2772 fps | 100% |
| Norma 217ᴾ | <<locked>> | 100% | 47,805 psi | 69% | 2697 fps | 100% |
| Norma MRP | <<locked>> | 90% | 59,828 psi | 86% | 2818 fps | 100% |
| Norma URP | <<locked>> | 86% | 62,279 psi | 89% | 2743 fps | 100% |
| Ramshot Grand | <<locked>> | 90% | 62,453 psi | 90% | 2858 fps | 100% |
| Ramshot Hunter | <<locked>> | 86% | 61,221 psi | 88% | 2759 fps | 100% |
| Ramshot Magnum | <<locked>> | 92% | 58,943 psi | 85% | 2769 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 38,377 psi | 55% | 1706 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 84% | 60,481 psi | 87% | 2740 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 84% | 59,335 psi | 85% | 2772 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 98% | 61,627 psi | 89% | 2913 fps | 100% |
| ReloadSwiss RS 80ᴾ | <<locked>> | 100% | 60,626 psi | 87% | 2890 fps | 100% |
| Rottweil R 904 | <<locked>> | 90% | 61,902 psi | 89% | 2756 fps | 100% |
| Rottweil R 905 | <<locked>> | 90% | 60,379 psi | 87% | 2769 fps | 100% |
| Rottweil R 907 | <<locked>> | 84% | 61,540 psi | 88% | 2713 fps | 100% |
| Shooters World Long Rifle | <<locked>> | 84% | 60,060 psi | 86% | 2677 fps | 100% |
| Shooters World SW4350 | <<locked>> | 86% | 62,207 psi | 89% | 2730 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 82% | 62,105 psi | 89% | 2549 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 84% | 59,103 psi | 85% | 2638 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 90% | 59,959 psi | 86% | 2766 fps | 100% |
| Somchem S355 | <<locked>> | 82% | 62,714 psi | 90% | 2684 fps | 100% |
| Somchem S361 | <<locked>> | 88% | 59,582 psi | 86% | 2703 fps | 100% |
| Somchem S365 | <<locked>> | 86% | 59,770 psi | 86% | 2694 fps | 100% |
| Somchem S385 | <<locked>> | 90% | 60,698 psi | 87% | 2736 fps | 100% |
| Unknown powder | <<locked>> | 84% | 62,439 psi | 90% | 2746 fps | 100% |
| Vihtavuori N150 | <<locked>> | 86% | 61,090 psi | 88% | 2621 fps | 100% |
| Vihtavuori N160 | <<locked>> | 84% | 62,743 psi | 90% | 2710 fps | 100% |
| Vihtavuori N165 | <<locked>> | 96% | 62,366 psi | 90% | 2743 fps | 100% |
| Vihtavuori N170ᴾ | <<locked>> | 100% | 53,156 psi | 76% | 2674 fps | 97.3% |
| Vihtavuori N550 | <<locked>> | 82% | 59,161 psi | 85% | 2710 fps | 100% |
| Vihtavuori N555 | <<locked>> | 90% | 59,437 psi | 85% | 2726 fps | 100% |
| Vihtavuori N560 | <<locked>> | 92% | 60,104 psi | 86% | 2838 fps | 100% |
| Vihtavuori N565 | <<locked>> | 96% | 59,596 psi | 86% | 2812 fps | 100% |
| Vihtavuori N568ᴾ | <<locked>> | 100% | 61,076 psi | 88% | 2884 fps | 100% |
| Vihtavuori N570ᴾ | <<locked>> | 100% | 58,523 psi | 84% | 2894 fps | 99.2% |
| Winchester 6.5 StaBALL | <<locked>> | 84% | 59,669 psi | 86% | 2641 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 94% | 61,119 psi | 88% | 2841 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 90% | 62,555 psi | 90% | 2759 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% | 58,001 psi | 83% | 2625 fps | 100% |
| Accurate 3100 | <<locked>> | 80% | 39,537 psi | 57% | 2408 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 52,663 psi | 76% | 2615 fps | 100% |
| Accurate MAGPRO | <<locked>> | 80% | 38,740 psi | 56% | 2484 fps | 96.6% |
| ADI APS 450 | <<locked>> | 80% | 59,335 psi | 85% | 2054 fps | 100% |
| ADI AR 2209 | <<locked>> | 80% | 43,859 psi | 63% | 2533 fps | 99.7% |
| ADI AR 2213 | <<locked>> | 80% | 39,146 psi | 56% | 2480 fps | 98.3% |
| ADI AR 2217 | <<locked>> | 82% | 31,067 psi | 45% | 2297 fps | 95.9% |
| ADI AR 2218 | <<locked>> | 94% | 40,030 psi | 57% | 2582 fps | 95.3% |
| ADI AR 2225 | <<locked>> | 80% | 26,339 psi | 38% | 2211 fps | 96.8% |
| Alliant Power Pro Varmint | <<locked>> | 80% | 44,309 psi | 64% | 2533 fps | 99.7% |
| Alliant Reloder-16 | <<locked>> | 80% | 50,691 psi | 73% | 2621 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 43,903 psi | 63% | 2530 fps | 99.7% |
| Alliant Reloder-22 | <<locked>> | 80% | 39,653 psi | 57% | 2487 fps | 99.3% |
| Alliant Reloder-23 | <<locked>> | 80% | 38,551 psi | 55% | 2428 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 33,054 psi | 47% | 2375 fps | 99.9% |
| Alliant Reloder-26 | <<locked>> | 80% | 42,960 psi | 62% | 2579 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 92% | 40,248 psi | 58% | 2579 fps | 95.9% |
| Alliant Reloder-50 | <<locked>> | 98% | 42,337 psi | 61% | 2621 fps | 96% |
| Baschieri & Pellagri 109 | <<locked>> | 80% | 38,551 psi | 55% | 2408 fps | 95.1% |
| Bofors RP15 | <<locked>> | 80% | 36,927 psi | 53% | 2428 fps | 98.7% |
| Bofors RP30 | <<locked>> | 80% | 30,501 psi | 44% | 2313 fps | 96.1% |
| Bofors RP5 | <<locked>> | 80% | 39,653 psi | 57% | 2487 fps | 99.3% |
| Bofors RP7 | <<locked>> | 80% | 54,259 psi | 78% | 2618 fps | 100% |
| Hodgdon H1000 | <<locked>> | 80% | 29,762 psi | 43% | 2264 fps | 95.9% |
| Hodgdon H4350 | <<locked>> | 80% | 52,040 psi | 75% | 2618 fps | 100% |
| Hodgdon H4831 | <<locked>> | 80% | 36,854 psi | 53% | 2379 fps | 97% |
| Hodgdon H4831 SC | <<locked>> | 80% | 41,002 psi | 59% | 2464 fps | 98.1% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 47,587 psi | 68% | 2507 fps | 100% |
| Hodgdon Retumbo | 79.9 gr | 80% | 32,314 psi | 46% | 2411 fps | 98.4% |
| Hodgdon Superformance | <<locked>> | 80% | 54,650 psi | 79% | 2710 fps | 100% |
| Hodgdon TrailBoss | <<locked>> | 80% | 28,137 psi | 40% | 1490 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 59,001 psi | 85% | 2631 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 80% | 57,087 psi | 82% | 2631 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 49,603 psi | 71% | 2562 fps | 100% |
| IMR 4451 Enduron | <<locked>> | 80% | 55,651 psi | 80% | 2635 fps | 100% |
| IMR 4831 | <<locked>> | 80% | 45,252 psi | 65% | 2497 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 43,076 psi | 62% | 2470 fps | 98.6% |
| IMR 7828 SSC | <<locked>> | 80% | 40,364 psi | 58% | 2513 fps | 98.7% |
| IMR 7977 Enduron | <<locked>> | 92% | 50,662 psi | 73% | 2569 fps | 95% |
| IMR 8133 Enduron | <<locked>> | 86% | 29,225 psi | 42% | 2300 fps | 95.2% |
| Lovex S065 | <<locked>> | 80% | 53,214 psi | 76% | 2585 fps | 100% |
| Lovex S070 | <<locked>> | 80% | 51,503 psi | 74% | 2589 fps | 100% |
| Lovex S071 | <<locked>> | 80% | 34,011 psi | 49% | 2300 fps | 99.6% |
| Norma 204 | <<locked>> | 80% | 50,299 psi | 72% | 2615 fps | 100% |
| Norma 217 | <<locked>> | 82% | 25,454 psi | 37% | 2208 fps | 95.7% |
| Norma MRP | <<locked>> | 80% | 41,916 psi | 60% | 2549 fps | 100% |
| Norma URP | <<locked>> | 80% | 51,300 psi | 74% | 2602 fps | 100% |
| Ramshot Grand | <<locked>> | 80% | 42,351 psi | 61% | 2566 fps | 99.3% |
| Ramshot Hunter | <<locked>> | 80% | 50,270 psi | 72% | 2615 fps | 100% |
| Ramshot Magnum | <<locked>> | 80% | 36,999 psi | 53% | 2434 fps | 99.4% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,805 psi | 41% | 1526 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 52,852 psi | 76% | 2641 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 51,416 psi | 74% | 2671 fps | 100% |
| ReloadSwiss RS 76 | 85.5 gr | 80% | 31,241 psi | 45% | 2385 fps | 98.9% |
| ReloadSwiss RS 80 | <<locked>> | 84% | 32,735 psi | 47% | 2402 fps | 95.3% |
| Rottweil R 904 | <<locked>> | 80% | 45,020 psi | 65% | 2510 fps | 99.3% |
| Rottweil R 905 | <<locked>> | 80% | 43,352 psi | 62% | 2516 fps | 99.7% |
| Rottweil R 907 | <<locked>> | 80% | 54,259 psi | 78% | 2618 fps | 100% |
| Shooters World Long Rifle | <<locked>> | 80% | 53,214 psi | 76% | 2585 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 51,503 psi | 74% | 2589 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 58,595 psi | 84% | 2510 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 52,025 psi | 75% | 2546 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 43,018 psi | 62% | 2510 fps | 99.7% |
| Somchem S355 | <<locked>> | 80% | 59,016 psi | 85% | 2641 fps | 100% |
| Somchem S361 | <<locked>> | 80% | 45,730 psi | 66% | 2500 fps | 98.9% |
| Somchem S365 | <<locked>> | 80% | 48,747 psi | 70% | 2556 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 43,627 psi | 63% | 2490 fps | 99.9% |
| Unknown powder | <<locked>> | 80% | 54,810 psi | 79% | 2651 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 50,879 psi | 73% | 2497 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 54,911 psi | 79% | 2615 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 36,927 psi | 53% | 2359 fps | 99.1% |
| Vihtavuori N170 | <<locked>> | 94% | 43,787 psi | 63% | 2516 fps | 95% |
| Vihtavuori N550 | <<locked>> | 80% | 55,492 psi | 80% | 2661 fps | 100% |
| Vihtavuori N555 | <<locked>> | 80% | 42,757 psi | 61% | 2493 fps | 100% |
| Vihtavuori N560 | 81.2 gr | 80% | 39,842 psi | 57% | 2510 fps | 98.1% |
| Vihtavuori N565 | <<locked>> | 80% | 34,301 psi | 49% | 2379 fps | 96.7% |
| Vihtavuori N568 | <<locked>> | 84% | 34,243 psi | 49% | 2421 fps | 95.3% |
| Vihtavuori N570 | <<locked>> | 90% | 40,669 psi | 58% | 2592 fps | 95.6% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 51,953 psi | 75% | 2549 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 80% | 35,795 psi | 51% | 2480 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 43,758 psi | 63% | 2497 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 82 powders for .338 Lapua Mag. Ackley Improved loaded with the .338 | 275gr | CutEdge LZR. Hodgdon Retumbo delivers the highest muzzle velocity at 2,917 fps; across all powders the maximum-charge window runs from 1,667 fps to 2,917 fps. ADI AR 2217 gives the best case fill at 100 %, and 82 of the 82 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 275.0 gr projectile in 0.338" calls for a 1:9.0 twist; slower twists will usually not stabilise this weight. ADI AR 2217, ADI AR 2218, ADI AR 2225 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 | 275gr | CutEdge LZR 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.