Load Specifications
Load data in caliber .338 Lapua Mag. Ackley Improved with .338 | 275gr | Alaska Bullet Works Kodiak SP SPBC bullet and 73 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>> | 88% | 59,495 psi | 85% | 2713 fps | 100% |
| Accurate 8700ᴾ | <<locked>> | 100% | 46,253 psi | 66% | 2651 fps | 97.5% |
| Accurate MAGPRO | <<locked>> | 88% | 59,466 psi | 85% | 2848 fps | 100% |
| ADI APS 450 | <<locked>> | 82% | 61,496 psi | 88% | 2129 fps | 100% |
| ADI AR 2209 | <<locked>> | 86% | 60,669 psi | 87% | 2802 fps | 100% |
| ADI AR 2213 | <<locked>> | 88% | 59,364 psi | 85% | 2825 fps | 100% |
| ADI AR 2217 | <<locked>> | 98% | 62,323 psi | 90% | 2861 fps | 100% |
| ADI AR 2218ᴾ | <<locked>> | 100% | 58,378 psi | 84% | 2946 fps | 99.9% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 61,090 psi | 88% | 2877 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 82% | 61,076 psi | 88% | 2772 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 86% | 60,075 psi | 86% | 2789 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 88% | 59,756 psi | 86% | 2818 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 90% | 61,699 psi | 89% | 2762 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 94% | 62,308 psi | 90% | 2841 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 84% | 58,610 psi | 84% | 2808 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 98% | 60,437 psi | 87% | 2920 fps | 99.8% |
| Alliant Reloder-50ᴾ | <<locked>> | 100% | 55,738 psi | 80% | 2854 fps | 99.2% |
| Baschieri & Pellagri 109 | <<locked>> | 90% | 59,277 psi | 85% | 2792 fps | 99.7% |
| Bofors RP15 | <<locked>> | 92% | 62,772 psi | 90% | 2854 fps | 100% |
| Bofors RP30 | <<locked>> | 96% | 61,888 psi | 89% | 2874 fps | 100% |
| Bofors RP5 | <<locked>> | 88% | 59,756 psi | 86% | 2818 fps | 100% |
| Hodgdon H1000 | <<locked>> | 96% | 59,843 psi | 86% | 2825 fps | 100% |
| Hodgdon H4350 | <<locked>> | 82% | 61,366 psi | 88% | 2769 fps | 100% |
| Hodgdon H4831 | <<locked>> | 92% | 61,888 psi | 89% | 2808 fps | 100% |
| Hodgdon H4831 SC | <<locked>> | 88% | 60,945 psi | 88% | 2799 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 84% | 60,974 psi | 88% | 2690 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 94% | 61,888 psi | 89% | 2943 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,898 psi | 54% | 1713 fps | 100% |
| IMR 4350 | <<locked>> | 84% | 62,613 psi | 90% | 2759 fps | 100% |
| IMR 4831 | <<locked>> | 86% | 61,612 psi | 89% | 2733 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 88% | 61,975 psi | 89% | 2785 fps | 100% |
| IMR 7828 SSC | <<locked>> | 88% | 61,699 psi | 89% | 2864 fps | 100% |
| IMR 7977 Enduron | <<locked>> | 94% | 60,452 psi | 87% | 2746 fps | 97.7% |
| IMR 8133 Enduronᴾ | <<locked>> | 100% | 55,927 psi | 80% | 2815 fps | 100% |
| Lovex D100 | <<locked>> | 98% | 61,351 psi | 88% | 2802 fps | 97.1% |
| Lovex S065 | <<locked>> | 82% | 62,511 psi | 90% | 2726 fps | 100% |
| Lovex S070 | <<locked>> | 82% | 61,134 psi | 88% | 2736 fps | 100% |
| Lovex S071 | <<locked>> | 94% | 61,279 psi | 88% | 2736 fps | 100% |
| Norma 204 | <<locked>> | 82% | 60,495 psi | 87% | 2779 fps | 100% |
| Norma 217ᴾ | <<locked>> | 100% | 57,450 psi | 83% | 2835 fps | 100% |
| Norma MRP | <<locked>> | 86% | 59,915 psi | 86% | 2831 fps | 100% |
| Norma URP | <<locked>> | 82% | 61,424 psi | 88% | 2749 fps | 100% |
| Ramshot Grand | <<locked>> | 86% | 62,381 psi | 90% | 2874 fps | 100% |
| Ramshot Hunter | <<locked>> | 82% | 60,539 psi | 87% | 2769 fps | 100% |
| Ramshot LRTᴾ | <<locked>> | 100% | 57,885 psi | 83% | 2871 fps | 96.3% |
| Ramshot Magnum | <<locked>> | 88% | 59,263 psi | 85% | 2785 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 38,899 psi | 56% | 1752 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 82% | 62,990 psi | 90% | 2828 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 92% | 58,363 psi | 84% | 2877 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 96% | 61,917 psi | 89% | 2917 fps | 100% |
| Rottweil R 904 | <<locked>> | 86% | 61,017 psi | 88% | 2769 fps | 100% |
| Rottweil R 905 | <<locked>> | 86% | 60,060 psi | 86% | 2785 fps | 100% |
| Shooters World 50 BMG | <<locked>> | 98% | 61,351 psi | 88% | 2802 fps | 97.1% |
| Shooters World Long Rifle | <<locked>> | 82% | 62,511 psi | 90% | 2726 fps | 100% |
| Shooters World SW4350 | <<locked>> | 82% | 61,134 psi | 88% | 2736 fps | 100% |
| SNPE Vectan SP 13ᴾ | <<locked>> | 100% | 48,414 psi | 70% | 2661 fps | 97.6% |
| SNPE Vectan Tubal 7000 | <<locked>> | 82% | 61,453 psi | 88% | 2690 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 86% | 59,654 psi | 86% | 2779 fps | 100% |
| Somchem S361 | <<locked>> | 86% | 62,482 psi | 90% | 2766 fps | 100% |
| Somchem S365 | <<locked>> | 82% | 59,480 psi | 85% | 2703 fps | 100% |
| Somchem S385 | <<locked>> | 86% | 60,191 psi | 86% | 2749 fps | 100% |
| Vihtavuori 24N41ᴾ | <<locked>> | 100% | 58,595 psi | 84% | 2835 fps | 96.2% |
| Vihtavuori N150 | <<locked>> | 82% | 59,944 psi | 86% | 2628 fps | 100% |
| Vihtavuori N165 | <<locked>> | 92% | 62,134 psi | 89% | 2762 fps | 100% |
| Vihtavuori N170ᴾ | <<locked>> | 100% | 60,843 psi | 87% | 2805 fps | 99% |
| Vihtavuori N555 | <<locked>> | 86% | 59,799 psi | 86% | 2743 fps | 100% |
| Vihtavuori N560 | <<locked>> | 88% | 60,133 psi | 86% | 2858 fps | 100% |
| Vihtavuori N565 | <<locked>> | 92% | 60,307 psi | 87% | 2838 fps | 100% |
| Vihtavuori N568 | <<locked>> | 96% | 62,192 psi | 89% | 2913 fps | 100% |
| Vihtavuori N570 | <<locked>> | 96% | 60,002 psi | 86% | 2927 fps | 99.7% |
| Winchester 6.5 StaBALL | <<locked>> | 82% | 62,497 psi | 90% | 2687 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 88% | 58,508 psi | 84% | 2812 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 86% | 61,583 psi | 88% | 2769 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% | 45,730 psi | 66% | 2523 fps | 100% |
| Accurate 8700 | <<locked>> | 96% | 40,103 psi | 58% | 2533 fps | 95.7% |
| Accurate MAGPRO | <<locked>> | 80% | 45,150 psi | 65% | 2621 fps | 98.6% |
| ADI APS 450 | <<locked>> | 80% | 59,567 psi | 86% | 2106 fps | 100% |
| ADI AR 2209 | <<locked>> | 80% | 49,763 psi | 71% | 2644 fps | 100% |
| ADI AR 2213 | <<locked>> | 80% | 45,078 psi | 65% | 2608 fps | 99.6% |
| ADI AR 2217 | <<locked>> | 80% | 33,605 psi | 48% | 2375 fps | 97.6% |
| ADI AR 2218 | <<locked>> | 88% | 37,811 psi | 54% | 2552 fps | 95.3% |
| ADI AR 2225 | <<locked>> | 80% | 30,966 psi | 44% | 2356 fps | 99.3% |
| Alliant Reloder-16 | <<locked>> | 80% | 57,174 psi | 82% | 2723 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 49,603 psi | 71% | 2638 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 80% | 45,847 psi | 66% | 2608 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 80% | 44,643 psi | 64% | 2533 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 38,769 psi | 56% | 2497 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 80% | 50,720 psi | 73% | 2700 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 86% | 38,682 psi | 56% | 2549 fps | 95.9% |
| Alliant Reloder-50 | <<locked>> | 90% | 38,595 psi | 55% | 2546 fps | 95.3% |
| Baschieri & Pellagri 109 | <<locked>> | 80% | 43,047 psi | 62% | 2523 fps | 97.3% |
| Bofors RP15 | <<locked>> | 80% | 42,612 psi | 61% | 2549 fps | 99.8% |
| Bofors RP30 | <<locked>> | 80% | 36,216 psi | 52% | 2448 fps | 98.5% |
| Bofors RP5 | <<locked>> | 80% | 45,847 psi | 66% | 2608 fps | 100% |
| Hodgdon H1000 | <<locked>> | 80% | 34,476 psi | 50% | 2398 fps | 98.4% |
| Hodgdon H4350 | <<locked>> | 80% | 57,769 psi | 83% | 2720 fps | 100% |
| Hodgdon H4831 | <<locked>> | 80% | 42,047 psi | 60% | 2500 fps | 98.8% |
| Hodgdon H4831 SC | <<locked>> | 80% | 46,746 psi | 67% | 2585 fps | 99.5% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 53,650 psi | 77% | 2602 fps | 100% |
| Hodgdon Retumbo | 88.6 gr | 80% | 37,942 psi | 55% | 2559 fps | 99.9% |
| Hodgdon TrailBoss | <<locked>> | 80% | 28,514 psi | 41% | 1529 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 55,274 psi | 79% | 2664 fps | 100% |
| IMR 4831 | <<locked>> | 80% | 51,271 psi | 74% | 2598 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 48,240 psi | 69% | 2582 fps | 99.7% |
| IMR 7828 SSC | <<locked>> | 80% | 46,717 psi | 67% | 2644 fps | 99.8% |
| IMR 7977 Enduron | <<locked>> | 88% | 50,024 psi | 72% | 2589 fps | 95.7% |
| IMR 8133 Enduron | <<locked>> | 80% | 28,543 psi | 41% | 2280 fps | 95.4% |
| Lovex D100 | <<locked>> | 94% | 53,287 psi | 77% | 2684 fps | 95.4% |
| Lovex S065 | <<locked>> | 80% | 58,914 psi | 85% | 2684 fps | 100% |
| Lovex S070 | <<locked>> | 80% | 57,421 psi | 82% | 2687 fps | 100% |
| Lovex S071 | <<locked>> | 80% | 39,523 psi | 57% | 2415 fps | 100% |
| Norma 204 | <<locked>> | 80% | 56,550 psi | 81% | 2726 fps | 100% |
| Norma 217 | <<locked>> | 80% | 28,790 psi | 41% | 2306 fps | 97.9% |
| Norma MRP | <<locked>> | 80% | 48,704 psi | 70% | 2671 fps | 100% |
| Norma URP | <<locked>> | 80% | 57,595 psi | 83% | 2700 fps | 100% |
| Ramshot Grand | <<locked>> | 80% | 49,690 psi | 71% | 2697 fps | 100% |
| Ramshot Hunter | <<locked>> | 80% | 56,681 psi | 81% | 2720 fps | 100% |
| Ramshot LRT | <<locked>> | 98% | 53,882 psi | 77% | 2808 fps | 95.4% |
| Ramshot Magnum | <<locked>> | 80% | 43,758 psi | 63% | 2566 fps | 100% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 29,341 psi | 42% | 1568 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 58,798 psi | 84% | 2779 fps | 100% |
| ReloadSwiss RS 76 | 94.8 gr | 80% | 37,159 psi | 53% | 2536 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 80% | 34,098 psi | 49% | 2438 fps | 96.5% |
| Rottweil R 904 | <<locked>> | 80% | 50,459 psi | 72% | 2618 fps | 99.9% |
| Rottweil R 905 | <<locked>> | 80% | 49,327 psi | 71% | 2631 fps | 100% |
| Shooters World 50 BMG | <<locked>> | 94% | 53,287 psi | 77% | 2684 fps | 95.4% |
| Shooters World Long Rifle | <<locked>> | 80% | 58,914 psi | 85% | 2684 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 57,421 psi | 82% | 2687 fps | 100% |
| SNPE Vectan SP 13 | <<locked>> | 94% | 39,537 psi | 57% | 2497 fps | 95.1% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 57,696 psi | 83% | 2644 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 48,979 psi | 70% | 2628 fps | 100% |
| Somchem S361 | <<locked>> | 80% | 51,416 psi | 74% | 2612 fps | 99.8% |
| Somchem S365 | <<locked>> | 80% | 55,695 psi | 80% | 2657 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 49,748 psi | 71% | 2605 fps | 100% |
| Vihtavuori 24N41 | <<locked>> | 98% | 54,607 psi | 78% | 2772 fps | 95.3% |
| Vihtavuori N150 | <<locked>> | 80% | 56,405 psi | 81% | 2585 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 42,250 psi | 61% | 2474 fps | 99.9% |
| Vihtavuori N170 | <<locked>> | 88% | 41,742 psi | 60% | 2493 fps | 95.1% |
| Vihtavuori N555 | <<locked>> | 80% | 49,371 psi | 71% | 2605 fps | 100% |
| Vihtavuori N560 | <<locked>> | 80% | 45,992 psi | 66% | 2638 fps | 99.5% |
| Vihtavuori N565 | <<locked>> | 80% | 40,335 psi | 58% | 2513 fps | 98.8% |
| Vihtavuori N568 | <<locked>> | 80% | 35,360 psi | 51% | 2451 fps | 96.3% |
| Vihtavuori N570 | 97.5 gr | 84% | 38,943 psi | 56% | 2562 fps | 95.5% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 58,392 psi | 84% | 2641 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 80% | 43,555 psi | 63% | 2608 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 49,922 psi | 72% | 2612 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 76 powders for .338 Lapua Mag. Ackley Improved loaded with the .338 | 275gr | Alaska Bullet Works Kodiak SP SPBC. ADI AR 2218 delivers the highest muzzle velocity at 2,946 fps; across all powders the maximum-charge window runs from 1,713 fps to 2,946 fps. Accurate 8700 gives the best case fill at 100 %, and 76 of the 76 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 1:15.0 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. Vihtavuori N570, Hodgdon Retumbo, ReloadSwiss RS 76 rank at the top here: for .338 Lapua Mag. Ackley Improved with the .338 | 275gr | Alaska Bullet Works Kodiak SP SPBC they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, Hodgdon 50BMG, Hodgdon US 869 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.