Load Specifications
Load data in caliber .338 Lapua Mag. Ackley Improved with .338 | 300gr | Hornady A-TIP bullet and 74 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Vihtavuori N570, Hodgdon Retumbo and ReloadSwiss RS 76.
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 3100 | <<locked>> | 90% | 62,888 psi | 90% | 2625 fps | 100% |
| Accurate 8700ᴾ | <<locked>> | 100% | 45,585 psi | 65% | 2533 fps | 97.9% |
| Accurate MAGPRO | <<locked>> | 88% | 62,178 psi | 89% | 2756 fps | 100% |
| ADI APS 450 | <<locked>> | 82% | 61,525 psi | 88% | 2011 fps | 100% |
| ADI AR 2209 | <<locked>> | 86% | 60,249 psi | 87% | 2664 fps | 100% |
| ADI AR 2213 | <<locked>> | 90% | 62,772 psi | 90% | 2740 fps | 100% |
| ADI AR 2217 | <<locked>> | 98% | 61,467 psi | 88% | 2723 fps | 100% |
| ADI AR 2218ᴾ | <<locked>> | 100% | 57,479 psi | 83% | 2812 fps | 99.9% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 60,205 psi | 86% | 2743 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 86% | 60,408 psi | 87% | 2664 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 82% | 60,640 psi | 87% | 2635 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 86% | 59,741 psi | 86% | 2657 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 88% | 59,205 psi | 85% | 2684 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 90% | 60,959 psi | 88% | 2625 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 94% | 61,496 psi | 88% | 2707 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 86% | 62,279 psi | 89% | 2723 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 98% | 59,408 psi | 85% | 2785 fps | 99.9% |
| Alliant Reloder-50ᴾ | <<locked>> | 100% | 54,781 psi | 79% | 2723 fps | 99.4% |
| Baschieri & Pellagri 109 | <<locked>> | 92% | 62,613 psi | 90% | 2710 fps | 100% |
| Bofors RP15 | <<locked>> | 92% | 62,323 psi | 90% | 2720 fps | 100% |
| Bofors RP30 | <<locked>> | 96% | 61,264 psi | 88% | 2736 fps | 100% |
| Bofors RP5 | <<locked>> | 88% | 59,205 psi | 85% | 2684 fps | 100% |
| Hodgdon H1000 | <<locked>> | 94% | 59,074 psi | 85% | 2690 fps | 100% |
| Hodgdon H4831 | <<locked>> | 88% | 61,627 psi | 89% | 2677 fps | 100% |
| Hodgdon H4831 SC | <<locked>> | 88% | 60,437 psi | 87% | 2661 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 84% | 60,539 psi | 87% | 2556 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 94% | 60,959 psi | 88% | 2802 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,898 psi | 54% | 1614 fps | 100% |
| IMR 4350 | <<locked>> | 84% | 62,134 psi | 89% | 2625 fps | 100% |
| IMR 4831 | <<locked>> | 82% | 59,451 psi | 85% | 2575 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 88% | 61,482 psi | 88% | 2648 fps | 100% |
| IMR 7828 SSC | <<locked>> | 90% | 61,119 psi | 88% | 2726 fps | 100% |
| IMR 7977 Enduron | <<locked>> | 94% | 60,002 psi | 86% | 2615 fps | 98.1% |
| IMR 8133 Enduronᴾ | <<locked>> | 100% | 55,187 psi | 79% | 2684 fps | 100% |
| Lovex D100 | <<locked>> | 98% | 60,553 psi | 87% | 2671 fps | 97.4% |
| Lovex S065 | <<locked>> | 82% | 62,163 psi | 89% | 2592 fps | 100% |
| Lovex S070 | <<locked>> | 82% | 60,872 psi | 87% | 2602 fps | 100% |
| Lovex S071 | <<locked>> | 94% | 60,713 psi | 87% | 2602 fps | 100% |
| Norma 204 | <<locked>> | 82% | 59,959 psi | 86% | 2644 fps | 100% |
| Norma 217ᴾ | <<locked>> | 100% | 56,550 psi | 81% | 2700 fps | 100% |
| Norma MRP | <<locked>> | 86% | 59,408 psi | 85% | 2697 fps | 100% |
| Norma URP | <<locked>> | 82% | 61,134 psi | 88% | 2615 fps | 100% |
| Ramshot Grand | <<locked>> | 90% | 62,932 psi | 90% | 2749 fps | 100% |
| Ramshot Hunter | <<locked>> | 82% | 60,017 psi | 86% | 2631 fps | 100% |
| Ramshot LRTᴾ | <<locked>> | 100% | 57,014 psi | 82% | 2740 fps | 96.7% |
| Ramshot Magnum | <<locked>> | 92% | 61,076 psi | 88% | 2680 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 38,972 psi | 56% | 1654 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 82% | 62,395 psi | 90% | 2690 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 94% | 61,975 psi | 89% | 2792 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 96% | 60,988 psi | 88% | 2782 fps | 100% |
| Rottweil R 904 | <<locked>> | 86% | 60,524 psi | 87% | 2635 fps | 100% |
| Rottweil R 905 | <<locked>> | 86% | 59,625 psi | 86% | 2648 fps | 100% |
| Shooters World 50 BMG | <<locked>> | 98% | 60,553 psi | 87% | 2671 fps | 97.4% |
| Shooters World Long Rifle | <<locked>> | 82% | 62,163 psi | 89% | 2592 fps | 100% |
| Shooters World SW4350 | <<locked>> | 82% | 60,872 psi | 87% | 2602 fps | 100% |
| SNPE Vectan SP 13ᴾ | <<locked>> | 100% | 47,790 psi | 69% | 2543 fps | 98% |
| SNPE Vectan Tubal 7000 | <<locked>> | 82% | 61,032 psi | 88% | 2556 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 86% | 59,219 psi | 85% | 2644 fps | 100% |
| Somchem S361 | <<locked>> | 86% | 62,004 psi | 89% | 2631 fps | 100% |
| Somchem S365 | <<locked>> | 84% | 62,917 psi | 90% | 2612 fps | 100% |
| Somchem S385 | <<locked>> | 86% | 59,756 psi | 86% | 2615 fps | 100% |
| Vihtavuori 24N41ᴾ | <<locked>> | 100% | 55,259 psi | 79% | 2654 fps | 96% |
| Vihtavuori N160 | <<locked>> | 82% | 62,685 psi | 90% | 2602 fps | 100% |
| Vihtavuori N165 | <<locked>> | 90% | 59,654 psi | 86% | 2605 fps | 100% |
| Vihtavuori N170 | <<locked>> | 96% | 62,656 psi | 90% | 2707 fps | 99.4% |
| Vihtavuori N550 | <<locked>> | 82% | 61,699 psi | 89% | 2612 fps | 100% |
| Vihtavuori N555 | <<locked>> | 86% | 59,190 psi | 85% | 2605 fps | 100% |
| Vihtavuori N560 | <<locked>> | 88% | 62,801 psi | 90% | 2759 fps | 100% |
| Vihtavuori N565 | <<locked>> | 92% | 59,509 psi | 85% | 2700 fps | 100% |
| Vihtavuori N568 | <<locked>> | 96% | 61,424 psi | 88% | 2779 fps | 100% |
| Vihtavuori N570 | <<locked>> | 98% | 62,903 psi | 90% | 2848 fps | 99.9% |
| Winchester 6.5 StaBALL | <<locked>> | 82% | 61,888 psi | 89% | 2552 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 90% | 61,989 psi | 89% | 2723 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 88% | 59,538 psi | 86% | 2618 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% | 45,368 psi | 65% | 2402 fps | 100% |
| Accurate 8700 | <<locked>> | 94% | 36,883 psi | 53% | 2365 fps | 95.2% |
| Accurate MAGPRO | <<locked>> | 80% | 47,181 psi | 68% | 2543 fps | 99.6% |
| ADI APS 450 | <<locked>> | 80% | 59,437 psi | 85% | 1985 fps | 100% |
| ADI AR 2209 | <<locked>> | 80% | 49,487 psi | 71% | 2520 fps | 100% |
| ADI AR 2213 | <<locked>> | 80% | 44,672 psi | 64% | 2484 fps | 99.8% |
| ADI AR 2217 | <<locked>> | 80% | 33,344 psi | 48% | 2267 fps | 98.1% |
| ADI AR 2218 | <<locked>> | 88% | 37,463 psi | 54% | 2444 fps | 96% |
| ADI AR 2225 | <<locked>> | 80% | 30,719 psi | 44% | 2254 fps | 99.6% |
| Alliant Power Pro Varmint | <<locked>> | 80% | 49,748 psi | 71% | 2516 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 56,869 psi | 82% | 2589 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 49,269 psi | 71% | 2513 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 80% | 45,440 psi | 65% | 2487 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 80% | 44,208 psi | 64% | 2411 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 38,479 psi | 55% | 2382 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 80% | 50,314 psi | 72% | 2575 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 84% | 35,592 psi | 51% | 2379 fps | 95.5% |
| Alliant Reloder-50 | <<locked>> | 90% | 37,942 psi | 55% | 2431 fps | 95.9% |
| Baschieri & Pellagri 109 | <<locked>> | 80% | 42,815 psi | 62% | 2408 fps | 97.8% |
| Bofors RP15 | <<locked>> | 80% | 42,308 psi | 61% | 2431 fps | 99.9% |
| Bofors RP30 | <<locked>> | 80% | 35,911 psi | 52% | 2339 fps | 98.9% |
| Bofors RP5 | <<locked>> | 80% | 45,440 psi | 65% | 2487 fps | 100% |
| Hodgdon H1000 | <<locked>> | 80% | 36,245 psi | 52% | 2333 fps | 99.3% |
| Hodgdon H4831 | <<locked>> | 80% | 47,094 psi | 68% | 2474 fps | 99.7% |
| Hodgdon H4831 SC | <<locked>> | 80% | 46,354 psi | 67% | 2461 fps | 99.7% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 53,447 psi | 77% | 2474 fps | 100% |
| Hodgdon Retumbo | 82.2 gr | 80% | 37,623 psi | 54% | 2441 fps | 100% |
| Hodgdon TrailBoss | <<locked>> | 80% | 28,456 psi | 41% | 1440 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 55,042 psi | 79% | 2536 fps | 100% |
| IMR 4831 | <<locked>> | 80% | 55,854 psi | 80% | 2533 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 48,008 psi | 69% | 2461 fps | 99.8% |
| IMR 7828 SSC | <<locked>> | 80% | 43,540 psi | 63% | 2470 fps | 99.7% |
| IMR 7977 Enduron | <<locked>> | 86% | 46,572 psi | 67% | 2415 fps | 95.4% |
| IMR 8133 Enduron | <<locked>> | 80% | 28,239 psi | 41% | 2178 fps | 96.2% |
| Lovex D100 | <<locked>> | 92% | 49,023 psi | 70% | 2507 fps | 95% |
| Lovex S065 | <<locked>> | 80% | 58,537 psi | 84% | 2546 fps | 100% |
| Lovex S070 | <<locked>> | 80% | 57,116 psi | 82% | 2556 fps | 100% |
| Lovex S071 | <<locked>> | 80% | 39,305 psi | 56% | 2300 fps | 100% |
| Norma 204 | <<locked>> | 80% | 56,130 psi | 81% | 2595 fps | 100% |
| Norma 217 | <<locked>> | 80% | 28,529 psi | 41% | 2205 fps | 98.4% |
| Norma MRP | <<locked>> | 80% | 48,356 psi | 69% | 2546 fps | 100% |
| Norma URP | <<locked>> | 80% | 57,276 psi | 82% | 2569 fps | 100% |
| Ramshot Grand | <<locked>> | 80% | 43,859 psi | 63% | 2487 fps | 99.9% |
| Ramshot Hunter | <<locked>> | 80% | 56,275 psi | 81% | 2585 fps | 100% |
| Ramshot LRT | <<locked>> | 98% | 53,171 psi | 76% | 2684 fps | 95.9% |
| Ramshot Magnum | <<locked>> | 80% | 39,436 psi | 57% | 2375 fps | 100% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 29,341 psi | 42% | 1476 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 58,320 psi | 84% | 2641 fps | 100% |
| ReloadSwiss RS 76 | 87.9 gr | 80% | 36,695 psi | 53% | 2418 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 80% | 33,591 psi | 48% | 2326 fps | 97% |
| Rottweil R 904 | <<locked>> | 80% | 50,140 psi | 72% | 2493 fps | 100% |
| Rottweil R 905 | <<locked>> | 80% | 49,023 psi | 70% | 2503 fps | 100% |
| Shooters World 50 BMG | <<locked>> | 92% | 49,023 psi | 70% | 2507 fps | 95% |
| Shooters World Long Rifle | <<locked>> | 80% | 58,537 psi | 84% | 2546 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 57,116 psi | 82% | 2556 fps | 100% |
| SNPE Vectan SP 13 | <<locked>> | 94% | 38,972 psi | 56% | 2385 fps | 95.6% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 57,319 psi | 82% | 2510 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 48,689 psi | 70% | 2503 fps | 100% |
| Somchem S361 | <<locked>> | 80% | 51,053 psi | 73% | 2487 fps | 99.9% |
| Somchem S365 | <<locked>> | 80% | 55,405 psi | 80% | 2526 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 49,313 psi | 71% | 2477 fps | 100% |
| Vihtavuori 24N41 | <<locked>> | 98% | 51,416 psi | 74% | 2598 fps | 95.1% |
| Vihtavuori N160 | <<locked>> | 80% | 58,726 psi | 84% | 2556 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 43,221 psi | 62% | 2375 fps | 100% |
| Vihtavuori N170 | <<locked>> | 82% | 39,407 psi | 57% | 2343 fps | 95% |
| Vihtavuori N550 | <<locked>> | 80% | 57,914 psi | 83% | 2566 fps | 100% |
| Vihtavuori N555 | <<locked>> | 80% | 48,950 psi | 70% | 2477 fps | 100% |
| Vihtavuori N560 | <<locked>> | 80% | 47,935 psi | 69% | 2552 fps | 99.9% |
| Vihtavuori N565 | <<locked>> | 80% | 39,958 psi | 57% | 2398 fps | 99.1% |
| Vihtavuori N568 | <<locked>> | 80% | 34,983 psi | 50% | 2343 fps | 96.9% |
| Vihtavuori N570 | 87.4 gr | 82% | 35,694 psi | 51% | 2388 fps | 95.1% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 57,914 psi | 83% | 2510 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 80% | 43,062 psi | 62% | 2484 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 45,571 psi | 65% | 2428 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 74 powders for .338 Lapua Mag. Ackley Improved loaded with the .338 | 300gr | Hornady A-TIP. Vihtavuori N570 delivers the highest muzzle velocity at 2,848 fps; across all powders the maximum-charge window runs from 1,614 fps to 2,848 fps. Accurate 8700 gives the best case fill at 100 %, and 74 of the 74 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 300.0 gr projectile in 0.338" calls for a 1:10.5 twist; slower twists will usually not stabilise this weight. Accurate 8700, 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. Vihtavuori N570, Hodgdon Retumbo, ReloadSwiss RS 76 rank at the top here: for .338 Lapua Mag. Ackley Improved with the .338 | 300gr | Hornady A-TIP 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.