Load Specifications
Load data in caliber .338 Lapua Mag. Ackley Improved with .338 | 307gr | Hornady Sub-X bullet and 60 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Vihtavuori N570, Alliant Reloder-33 and ADI AR 2218.
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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Max Load - Barrel Length: 27"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 3100 | <<locked>> | 86% | 59,654 psi | 86% | 2575 fps | 100% |
| Accurate 8700ᴾ | <<locked>> | 100% | 50,778 psi | 73% | 2602 fps | 99.2% |
| Accurate MAGPRO | <<locked>> | 84% | 58,900 psi | 85% | 2703 fps | 100% |
| ADI APS 450 | <<locked>> | 82% | 61,728 psi | 89% | 2024 fps | 100% |
| ADI AR 2209 | <<locked>> | 84% | 60,539 psi | 87% | 2654 fps | 100% |
| ADI AR 2213 | <<locked>> | 86% | 59,422 psi | 85% | 2684 fps | 100% |
| ADI AR 2217 | <<locked>> | 96% | 62,874 psi | 90% | 2723 fps | 100% |
| ADI AR 2218 | <<locked>> | 98% | 59,001 psi | 85% | 2822 fps | 100% |
| ADI AR 2225 | <<locked>> | 98% | 62,308 psi | 90% | 2743 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 84% | 60,002 psi | 86% | 2648 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 86% | 59,915 psi | 86% | 2677 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 88% | 62,018 psi | 89% | 2618 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 90% | 58,929 psi | 85% | 2657 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 82% | 59,088 psi | 85% | 2667 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 96% | 61,322 psi | 88% | 2795 fps | 100% |
| Alliant Reloder-50ᴾ | <<locked>> | 100% | 61,206 psi | 88% | 2795 fps | 100% |
| Baschieri & Pellagri 109 | <<locked>> | 90% | 62,975 psi | 90% | 2707 fps | 100% |
| Bofors RP15 | <<locked>> | 88% | 59,248 psi | 85% | 2667 fps | 100% |
| Bofors RP30 | <<locked>> | 94% | 62,685 psi | 90% | 2740 fps | 100% |
| Bofors RP5 | <<locked>> | 86% | 59,915 psi | 86% | 2677 fps | 100% |
| Hodgdon H1000 | <<locked>> | 92% | 60,336 psi | 87% | 2687 fps | 100% |
| Hodgdon H4831 | <<locked>> | 86% | 61,888 psi | 89% | 2671 fps | 100% |
| Hodgdon H4831 SC | <<locked>> | 86% | 60,785 psi | 87% | 2657 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 82% | 60,930 psi | 88% | 2546 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 90% | 58,885 psi | 85% | 2753 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 38,087 psi | 55% | 1624 fps | 100% |
| Hodgdon US 869ᴾ | <<locked>> | 100% | 55,666 psi | 80% | 2661 fps | 96.9% |
| IMR 4350 | <<locked>> | 82% | 62,294 psi | 89% | 2615 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 86% | 61,670 psi | 89% | 2641 fps | 100% |
| IMR 7828 SSC | <<locked>> | 88% | 62,192 psi | 89% | 2726 fps | 100% |
| IMR 7977 Enduron | <<locked>> | 92% | 60,162 psi | 86% | 2615 fps | 98.6% |
| IMR 8133 Enduronᴾ | <<locked>> | 100% | 60,872 psi | 87% | 2740 fps | 100% |
| Lovex D100 | <<locked>> | 96% | 61,583 psi | 88% | 2680 fps | 98.2% |
| Lovex S071 | <<locked>> | 92% | 61,670 psi | 89% | 2598 fps | 100% |
| Norma 217ᴾ | <<locked>> | 100% | 62,642 psi | 90% | 2753 fps | 100% |
| Norma MRP | <<locked>> | 84% | 60,278 psi | 87% | 2690 fps | 100% |
| Ramshot Grand | <<locked>> | 86% | 59,857 psi | 86% | 2697 fps | 100% |
| Ramshot LRTᴾ | <<locked>> | 100% | 62,772 psi | 90% | 2815 fps | 98.4% |
| Ramshot Magnum | <<locked>> | 90% | 62,323 psi | 90% | 2680 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 39,146 psi | 56% | 1660 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 90% | 59,553 psi | 86% | 2743 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 94% | 62,714 psi | 90% | 2785 fps | 100% |
| Rottweil R 904 | <<locked>> | 84% | 60,800 psi | 87% | 2628 fps | 100% |
| Rottweil R 905 | <<locked>> | 84% | 60,031 psi | 86% | 2641 fps | 100% |
| Shooters World 50 BMG | <<locked>> | 96% | 61,583 psi | 88% | 2680 fps | 98.2% |
| SNPE Vectan SP 13ᴾ | <<locked>> | 100% | 52,649 psi | 76% | 2608 fps | 99.2% |
| SNPE Vectan Tubal 8000 | <<locked>> | 84% | 59,640 psi | 86% | 2638 fps | 100% |
| Somchem S361 | <<locked>> | 84% | 62,163 psi | 89% | 2625 fps | 100% |
| Somchem S385 | <<locked>> | 84% | 60,176 psi | 86% | 2608 fps | 100% |
| Vihtavuori 20N29ᴾ | <<locked>> | 100% | 46,108 psi | 66% | 2530 fps | 96.8% |
| Vihtavuori 24N41ᴾ | <<locked>> | 100% | 60,756 psi | 87% | 2726 fps | 97.7% |
| Vihtavuori N165 | <<locked>> | 88% | 60,350 psi | 87% | 2602 fps | 100% |
| Vihtavuori N170 | <<locked>> | 92% | 59,408 psi | 85% | 2657 fps | 99.5% |
| Vihtavuori N555 | <<locked>> | 84% | 60,104 psi | 86% | 2602 fps | 100% |
| Vihtavuori N560 | <<locked>> | 84% | 59,495 psi | 85% | 2703 fps | 100% |
| Vihtavuori N565 | <<locked>> | 90% | 60,771 psi | 87% | 2703 fps | 100% |
| Vihtavuori N568 | <<locked>> | 92% | 58,769 psi | 84% | 2730 fps | 100% |
| Vihtavuori N570 | <<locked>> | 94% | 60,321 psi | 87% | 2799 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 86% | 59,495 psi | 85% | 2671 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 86% | 60,017 psi | 86% | 2612 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 3100 | <<locked>> | 80% | 49,066 psi | 70% | 2441 fps | 100% |
| Accurate 8700 | <<locked>> | 90% | 35,520 psi | 51% | 2326 fps | 95.5% |
| Accurate MAGPRO | <<locked>> | 80% | 51,343 psi | 74% | 2595 fps | 100% |
| ADI APS 450 | <<locked>> | 80% | 59,582 psi | 86% | 1995 fps | 100% |
| ADI AR 2209 | <<locked>> | 80% | 53,156 psi | 76% | 2562 fps | 100% |
| ADI AR 2213 | <<locked>> | 80% | 48,428 psi | 70% | 2533 fps | 100% |
| ADI AR 2217 | <<locked>> | 80% | 36,390 psi | 52% | 2326 fps | 99.3% |
| ADI AR 2218 | 97 gr | 84% | 35,708 psi | 51% | 2395 fps | 96.2% |
| ADI AR 2225 | <<locked>> | 80% | 33,678 psi | 48% | 2306 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 52,910 psi | 76% | 2552 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 80% | 49,168 psi | 71% | 2530 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 80% | 48,037 psi | 69% | 2448 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 42,177 psi | 61% | 2425 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 80% | 55,056 psi | 79% | 2618 fps | 100% |
| Alliant Reloder-33 | 94.1 gr | 80% | 34,156 psi | 49% | 2333 fps | 95.6% |
| Alliant Reloder-50 | <<locked>> | 84% | 34,316 psi | 49% | 2336 fps | 95.1% |
| Baschieri & Pellagri 109 | <<locked>> | 80% | 45,832 psi | 66% | 2457 fps | 98.9% |
| Bofors RP15 | <<locked>> | 80% | 45,963 psi | 66% | 2480 fps | 100% |
| Bofors RP30 | <<locked>> | 80% | 39,407 psi | 57% | 2392 fps | 99.7% |
| Bofors RP5 | <<locked>> | 80% | 49,168 psi | 71% | 2530 fps | 100% |
| Hodgdon H1000 | <<locked>> | 80% | 39,624 psi | 57% | 2385 fps | 99.9% |
| Hodgdon H4831 | <<locked>> | 80% | 50,778 psi | 73% | 2520 fps | 100% |
| Hodgdon H4831 SC | <<locked>> | 80% | 49,835 psi | 72% | 2507 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 57,217 psi | 82% | 2503 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 80% | 41,423 psi | 60% | 2497 fps | 100% |
| Hodgdon TrailBoss | <<locked>> | 80% | 28,660 psi | 41% | 1450 fps | 100% |
| Hodgdon US 869 | <<locked>> | 96% | 48,312 psi | 69% | 2546 fps | 95.2% |
| IMR 4350 | <<locked>> | 80% | 58,494 psi | 84% | 2569 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 51,155 psi | 73% | 2500 fps | 100% |
| IMR 7828 SSC | <<locked>> | 80% | 47,398 psi | 68% | 2523 fps | 100% |
| IMR 7977 Enduron | <<locked>> | 82% | 43,859 psi | 63% | 2365 fps | 95.5% |
| IMR 8133 Enduron | <<locked>> | 80% | 31,299 psi | 45% | 2241 fps | 98% |
| Lovex D100 | <<locked>> | 88% | 46,470 psi | 67% | 2457 fps | 95.1% |
| Lovex S071 | <<locked>> | 80% | 42,525 psi | 61% | 2343 fps | 100% |
| Norma 217 | <<locked>> | 80% | 31,792 psi | 46% | 2264 fps | 99.6% |
| Norma MRP | <<locked>> | 80% | 52,620 psi | 76% | 2589 fps | 100% |
| Ramshot Grand | <<locked>> | 80% | 48,095 psi | 69% | 2539 fps | 100% |
| Ramshot LRT | <<locked>> | 92% | 47,456 psi | 68% | 2579 fps | 95.2% |
| Ramshot Magnum | <<locked>> | 80% | 43,265 psi | 62% | 2425 fps | 100% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 29,544 psi | 42% | 1486 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 80% | 40,770 psi | 59% | 2477 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 80% | 37,579 psi | 54% | 2395 fps | 98.7% |
| Rottweil R 904 | <<locked>> | 80% | 53,606 psi | 77% | 2533 fps | 100% |
| Rottweil R 905 | <<locked>> | 80% | 52,750 psi | 76% | 2546 fps | 100% |
| Shooters World 50 BMG | <<locked>> | 88% | 46,470 psi | 67% | 2457 fps | 95.1% |
| SNPE Vectan SP 13 | <<locked>> | 90% | 37,695 psi | 54% | 2346 fps | 95.9% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 52,402 psi | 75% | 2543 fps | 100% |
| Somchem S361 | <<locked>> | 80% | 54,592 psi | 78% | 2530 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 52,953 psi | 76% | 2516 fps | 100% |
| Vihtavuori 20N29 | <<locked>> | 96% | 40,089 psi | 58% | 2418 fps | 95% |
| Vihtavuori 24N41 | <<locked>> | 94% | 49,139 psi | 71% | 2556 fps | 95.3% |
| Vihtavuori N165 | <<locked>> | 80% | 46,644 psi | 67% | 2418 fps | 100% |
| Vihtavuori N170 | <<locked>> | 80% | 40,030 psi | 57% | 2346 fps | 96% |
| Vihtavuori N555 | <<locked>> | 80% | 52,924 psi | 76% | 2513 fps | 100% |
| Vihtavuori N560 | <<locked>> | 80% | 52,011 psi | 75% | 2598 fps | 100% |
| Vihtavuori N565 | <<locked>> | 80% | 43,685 psi | 63% | 2451 fps | 99.8% |
| Vihtavuori N568 | <<locked>> | 80% | 38,595 psi | 55% | 2402 fps | 98.5% |
| Vihtavuori N570 | 90.5 gr | 80% | 36,869 psi | 53% | 2402 fps | 96.3% |
| Winchester StaBALL HD | <<locked>> | 80% | 47,877 psi | 69% | 2526 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 49,153 psi | 71% | 2470 fps | 100% |
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 61 powders for .338 Lapua Mag. Ackley Improved loaded with the .338 | 307gr | Hornady Sub-X. ADI AR 2218 delivers the highest muzzle velocity at 2,822 fps; across all powders the maximum-charge window runs from 1,624 fps to 2,822 fps. Accurate 8700 gives the best case fill at 100 %, and 61 of the 61 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (480 MPa), the top charges use 55–90 %, leaving at least 10 % headroom. The 307.0 gr projectile in 0.338" calls for a 1:12.0 twist; slower twists will usually not stabilise this weight. Accurate 8700, Alliant Reloder-50, Hodgdon TrailBoss 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. Vihtavuori N570, Alliant Reloder-33, ADI AR 2218 rank at the top here: for .338 Lapua Mag. Ackley Improved with the .338 | 307gr | Hornady Sub-X 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.