Load Specifications
Load data in caliber .338 Lapua Mag. Ackley Improved with .338 | 300gr | Nosler Custom Competition bullet and 72 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Hodgdon Retumbo, Vihtavuori N570 and Alliant Reloder-33.
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>> | 88% | 60,278 psi | 87% | 2602 fps | 100% |
| Accurate 8700ᴾ | <<locked>> | 100% | 46,818 psi | 67% | 2556 fps | 98.2% |
| Accurate MAGPRO | <<locked>> | 88% | 60,278 psi | 87% | 2736 fps | 100% |
| ADI APS 450 | <<locked>> | 82% | 61,511 psi | 88% | 2021 fps | 100% |
| ADI AR 2209 | <<locked>> | 86% | 61,337 psi | 88% | 2684 fps | 100% |
| ADI AR 2213 | <<locked>> | 88% | 60,060 psi | 86% | 2710 fps | 100% |
| ADI AR 2217 | <<locked>> | 96% | 58,972 psi | 85% | 2697 fps | 100% |
| ADI AR 2218ᴾ | <<locked>> | 100% | 59,088 psi | 85% | 2838 fps | 100% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 62,018 psi | 89% | 2762 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 86% | 61,453 psi | 88% | 2680 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 86% | 61,453 psi | 88% | 2680 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 82% | 61,743 psi | 89% | 2651 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 86% | 60,771 psi | 87% | 2674 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 88% | 60,437 psi | 87% | 2700 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 90% | 62,294 psi | 89% | 2644 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 92% | 58,943 psi | 85% | 2677 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 84% | 59,553 psi | 86% | 2694 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 98% | 61,163 psi | 88% | 2812 fps | 100% |
| Alliant Reloder-50ᴾ | <<locked>> | 100% | 56,478 psi | 81% | 2749 fps | 99.6% |
| Baschieri & Pellagri 109 | <<locked>> | 90% | 59,930 psi | 86% | 2680 fps | 99.9% |
| Bofors RP15 | <<locked>> | 90% | 59,756 psi | 86% | 2694 fps | 100% |
| Bofors RP30 | <<locked>> | 96% | 62,656 psi | 90% | 2759 fps | 100% |
| Bofors RP5 | <<locked>> | 88% | 60,437 psi | 87% | 2700 fps | 100% |
| Hodgdon H1000 | <<locked>> | 96% | 60,727 psi | 87% | 2710 fps | 100% |
| Hodgdon H4350 | <<locked>> | 82% | 62,192 psi | 89% | 2651 fps | 100% |
| Hodgdon H4831 | <<locked>> | 92% | 62,598 psi | 90% | 2694 fps | 100% |
| Hodgdon H4831 SC | <<locked>> | 88% | 61,641 psi | 89% | 2680 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 84% | 61,743 psi | 89% | 2572 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 94% | 62,830 psi | 90% | 2825 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,898 psi | 54% | 1621 fps | 100% |
| IMR 4350 | <<locked>> | 82% | 59,567 psi | 86% | 2598 fps | 100% |
| IMR 4831 | <<locked>> | 86% | 62,308 psi | 90% | 2615 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 88% | 62,598 psi | 90% | 2667 fps | 100% |
| IMR 7828 SSC | <<locked>> | 88% | 62,598 psi | 90% | 2746 fps | 100% |
| IMR 7977 Enduron | <<locked>> | 94% | 61,090 psi | 88% | 2638 fps | 98.3% |
| IMR 8133 Enduronᴾ | <<locked>> | 100% | 56,695 psi | 81% | 2707 fps | 100% |
| Lovex D100 | <<locked>> | 98% | 62,062 psi | 89% | 2697 fps | 97.8% |
| Lovex S070 | <<locked>> | 82% | 61,830 psi | 89% | 2618 fps | 100% |
| Lovex S071 | <<locked>> | 94% | 61,989 psi | 89% | 2621 fps | 100% |
| Norma 204 | <<locked>> | 82% | 61,061 psi | 88% | 2661 fps | 100% |
| Norma 217ᴾ | <<locked>> | 100% | 58,160 psi | 84% | 2720 fps | 100% |
| Norma MRP | <<locked>> | 86% | 60,727 psi | 87% | 2713 fps | 100% |
| Norma URP | <<locked>> | 82% | 62,192 psi | 89% | 2631 fps | 100% |
| Ramshot Grand | <<locked>> | 84% | 58,740 psi | 84% | 2703 fps | 100% |
| Ramshot Hunter | <<locked>> | 82% | 61,105 psi | 88% | 2648 fps | 100% |
| Ramshot LRTᴾ | <<locked>> | 100% | 58,537 psi | 84% | 2769 fps | 97.2% |
| Ramshot Magnum | <<locked>> | 88% | 59,973 psi | 86% | 2671 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 38,972 psi | 56% | 1660 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 92% | 59,379 psi | 85% | 2766 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 96% | 62,656 psi | 90% | 2805 fps | 100% |
| Rottweil R 904 | <<locked>> | 86% | 61,554 psi | 88% | 2651 fps | 100% |
| Rottweil R 905 | <<locked>> | 86% | 60,727 psi | 87% | 2664 fps | 100% |
| Shooters World 50 BMG | <<locked>> | 98% | 62,062 psi | 89% | 2697 fps | 97.8% |
| Shooters World SW4350 | <<locked>> | 82% | 61,830 psi | 89% | 2618 fps | 100% |
| SNPE Vectan SP 13ᴾ | <<locked>> | 100% | 49,095 psi | 71% | 2566 fps | 98.3% |
| SNPE Vectan Tubal 7000 | <<locked>> | 82% | 62,047 psi | 89% | 2572 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 86% | 60,336 psi | 87% | 2664 fps | 100% |
| Somchem S361 | <<locked>> | 84% | 59,103 psi | 85% | 2602 fps | 100% |
| Somchem S365 | <<locked>> | 82% | 60,336 psi | 87% | 2589 fps | 100% |
| Somchem S385 | <<locked>> | 86% | 60,988 psi | 88% | 2635 fps | 100% |
| Vihtavuori 20N29ᴾ | <<locked>> | 100% | 47,036 psi | 68% | 2556 fps | 96.4% |
| Vihtavuori 24N41ᴾ | <<locked>> | 100% | 59,364 psi | 85% | 2730 fps | 97% |
| Vihtavuori N150 | <<locked>> | 82% | 60,597 psi | 87% | 2510 fps | 100% |
| Vihtavuori N165 | <<locked>> | 92% | 62,816 psi | 90% | 2644 fps | 100% |
| Vihtavuori N170ᴾ | <<locked>> | 100% | 61,598 psi | 88% | 2697 fps | 99.4% |
| Vihtavuori N555 | <<locked>> | 86% | 60,568 psi | 87% | 2628 fps | 100% |
| Vihtavuori N560 | <<locked>> | 88% | 60,930 psi | 88% | 2740 fps | 100% |
| Vihtavuori N565 | <<locked>> | 92% | 61,046 psi | 88% | 2723 fps | 100% |
| Vihtavuori N568 | <<locked>> | 96% | 62,917 psi | 90% | 2799 fps | 100% |
| Vihtavuori N570 | <<locked>> | 96% | 60,829 psi | 87% | 2818 fps | 99.9% |
| Winchester StaBALL HD | <<locked>> | 88% | 59,451 psi | 85% | 2697 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 86% | 62,221 psi | 89% | 2654 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% | 46,456 psi | 67% | 2421 fps | 100% |
| Accurate 8700 | <<locked>> | 94% | 37,913 psi | 54% | 2388 fps | 95.8% |
| Accurate MAGPRO | <<locked>> | 80% | 45,730 psi | 66% | 2520 fps | 99.2% |
| ADI APS 450 | <<locked>> | 80% | 59,480 psi | 85% | 1995 fps | 100% |
| ADI AR 2209 | <<locked>> | 80% | 50,473 psi | 73% | 2539 fps | 100% |
| ADI AR 2213 | <<locked>> | 80% | 45,759 psi | 66% | 2507 fps | 99.9% |
| ADI AR 2217 | <<locked>> | 80% | 34,127 psi | 49% | 2287 fps | 98.5% |
| ADI AR 2218 | <<locked>> | 86% | 35,839 psi | 51% | 2408 fps | 95.4% |
| ADI AR 2225 | <<locked>> | 80% | 31,444 psi | 45% | 2270 fps | 99.8% |
| Alliant Power Pro Varmint | <<locked>> | 80% | 50,821 psi | 73% | 2539 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 80% | 50,821 psi | 73% | 2539 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 58,015 psi | 83% | 2605 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 50,343 psi | 72% | 2533 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 80% | 46,514 psi | 67% | 2507 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 80% | 45,237 psi | 65% | 2428 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 39,465 psi | 57% | 2402 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 80% | 51,503 psi | 74% | 2592 fps | 100% |
| Alliant Reloder-33 | 95.1 gr | 84% | 36,651 psi | 53% | 2405 fps | 96% |
| Alliant Reloder-50 | <<locked>> | 88% | 36,477 psi | 52% | 2402 fps | 95.4% |
| Baschieri & Pellagri 109 | <<locked>> | 80% | 43,540 psi | 63% | 2428 fps | 98% |
| Bofors RP15 | <<locked>> | 80% | 43,250 psi | 62% | 2451 fps | 100% |
| Bofors RP30 | <<locked>> | 80% | 36,927 psi | 53% | 2362 fps | 99.1% |
| Bofors RP5 | <<locked>> | 80% | 46,514 psi | 67% | 2507 fps | 100% |
| Hodgdon H1000 | <<locked>> | 80% | 35,027 psi | 50% | 2310 fps | 99.1% |
| Hodgdon H4350 | <<locked>> | 80% | 58,378 psi | 84% | 2605 fps | 100% |
| Hodgdon H4831 | <<locked>> | 80% | 42,641 psi | 61% | 2402 fps | 99.3% |
| Hodgdon H4831 SC | <<locked>> | 80% | 47,355 psi | 68% | 2484 fps | 99.8% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 54,346 psi | 78% | 2487 fps | 100% |
| Hodgdon Retumbo | 83.9 gr | 80% | 38,566 psi | 55% | 2461 fps | 100% |
| Hodgdon TrailBoss | <<locked>> | 80% | 28,529 psi | 41% | 1447 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 55,941 psi | 80% | 2552 fps | 100% |
| IMR 4831 | <<locked>> | 80% | 51,880 psi | 75% | 2487 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 48,834 psi | 70% | 2477 fps | 99.9% |
| IMR 7828 SSC | <<locked>> | 80% | 47,413 psi | 68% | 2539 fps | 100% |
| IMR 7977 Enduron | <<locked>> | 84% | 44,556 psi | 64% | 2385 fps | 95% |
| IMR 8133 Enduron | <<locked>> | 80% | 29,022 psi | 42% | 2201 fps | 96.6% |
| Lovex D100 | <<locked>> | 92% | 50,270 psi | 72% | 2530 fps | 95.5% |
| Lovex S070 | <<locked>> | 80% | 58,073 psi | 83% | 2572 fps | 100% |
| Lovex S071 | <<locked>> | 80% | 40,118 psi | 58% | 2316 fps | 100% |
| Norma 204 | <<locked>> | 80% | 57,232 psi | 82% | 2612 fps | 100% |
| Norma 217 | <<locked>> | 80% | 29,356 psi | 42% | 2228 fps | 98.8% |
| Norma MRP | <<locked>> | 80% | 49,487 psi | 71% | 2566 fps | 100% |
| Norma URP | <<locked>> | 80% | 58,305 psi | 84% | 2585 fps | 100% |
| Ramshot Grand | <<locked>> | 80% | 50,502 psi | 73% | 2592 fps | 100% |
| Ramshot Hunter | <<locked>> | 80% | 57,392 psi | 82% | 2605 fps | 100% |
| Ramshot LRT | <<locked>> | 96% | 50,995 psi | 73% | 2651 fps | 95.5% |
| Ramshot Magnum | <<locked>> | 80% | 44,396 psi | 64% | 2464 fps | 100% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 29,399 psi | 42% | 1486 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 80% | 37,782 psi | 54% | 2441 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 80% | 34,664 psi | 50% | 2352 fps | 97.5% |
| Rottweil R 904 | <<locked>> | 80% | 51,097 psi | 73% | 2510 fps | 100% |
| Rottweil R 905 | <<locked>> | 80% | 49,995 psi | 72% | 2523 fps | 100% |
| Shooters World 50 BMG | <<locked>> | 92% | 50,270 psi | 72% | 2530 fps | 95.5% |
| Shooters World SW4350 | <<locked>> | 80% | 58,073 psi | 83% | 2572 fps | 100% |
| SNPE Vectan SP 13 | <<locked>> | 92% | 37,507 psi | 54% | 2359 fps | 95.2% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 58,233 psi | 84% | 2526 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 49,690 psi | 71% | 2520 fps | 100% |
| Somchem S361 | <<locked>> | 80% | 51,938 psi | 75% | 2507 fps | 100% |
| Somchem S365 | <<locked>> | 80% | 56,507 psi | 81% | 2543 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 50,401 psi | 72% | 2497 fps | 100% |
| Vihtavuori 20N29 | <<locked>> | 98% | 43,627 psi | 63% | 2497 fps | 95.5% |
| Vihtavuori 24N41 | <<locked>> | 96% | 51,532 psi | 74% | 2615 fps | 95.3% |
| Vihtavuori N150 | <<locked>> | 80% | 57,014 psi | 82% | 2470 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 42,844 psi | 62% | 2375 fps | 100% |
| Vihtavuori N170 | <<locked>> | 86% | 39,639 psi | 57% | 2349 fps | 95.2% |
| Vihtavuori N555 | <<locked>> | 80% | 50,009 psi | 72% | 2493 fps | 100% |
| Vihtavuori N560 | <<locked>> | 80% | 46,746 psi | 67% | 2536 fps | 99.8% |
| Vihtavuori N565 | <<locked>> | 80% | 40,944 psi | 59% | 2418 fps | 99.3% |
| Vihtavuori N568 | <<locked>> | 80% | 35,940 psi | 52% | 2362 fps | 97.3% |
| Vihtavuori N570 | 90.2 gr | 82% | 36,927 psi | 53% | 2415 fps | 95.7% |
| Winchester StaBALL HD | <<locked>> | 80% | 44,382 psi | 64% | 2503 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 50,575 psi | 73% | 2507 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 72 powders for .338 Lapua Mag. Ackley Improved loaded with the .338 | 300gr | Nosler Custom Competition. ADI AR 2218 delivers the highest muzzle velocity at 2,838 fps; across all powders the maximum-charge window runs from 1,621 fps to 2,838 fps. Accurate 8700 gives the best case fill at 100 %, and 72 of the 72 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 1:12.0 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. Hodgdon Retumbo, Vihtavuori N570, Alliant Reloder-33 rank at the top here: for .338 Lapua Mag. Ackley Improved with the .338 | 300gr | Nosler Custom Competition 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.