Load Specifications
Load data in caliber .338 Lapua Mag. Ackley Improved with .338 | 265gr | CutEdge MTH bullet and 80 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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Max Load - Barrel Length: 27"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2700 | <<locked>> | 82% | 62,381 psi | 90% | 2736 fps | 100% |
| Accurate 3100 | <<locked>> | 92% | 59,785 psi | 86% | 2759 fps | 100% |
| Accurate 4350 | <<locked>> | 84% | 60,553 psi | 87% | 2772 fps | 100% |
| Accurate MAGPRO | <<locked>> | 92% | 59,727 psi | 86% | 2890 fps | 99.8% |
| ADI APS 450 | <<locked>> | 82% | 61,337 psi | 88% | 2133 fps | 100% |
| ADI AR 2209 | <<locked>> | 90% | 61,772 psi | 89% | 2851 fps | 100% |
| ADI AR 2213 | <<locked>> | 92% | 59,944 psi | 86% | 2874 fps | 100% |
| ADI AR 2217ᴾ | <<locked>> | 100% | 58,059 psi | 83% | 2848 fps | 100% |
| ADI AR 2218ᴾ | <<locked>> | 100% | 50,212 psi | 72% | 2841 fps | 98.3% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 52,344 psi | 75% | 2812 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 86% | 62,004 psi | 89% | 2825 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 90% | 61,046 psi | 88% | 2841 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 92% | 60,060 psi | 86% | 2861 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 94% | 61,656 psi | 89% | 2808 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 98% | 61,873 psi | 89% | 2884 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 88% | 58,537 psi | 84% | 2858 fps | 100% |
| Alliant Reloder-33ᴾ | <<locked>> | 100% | 55,158 psi | 79% | 2887 fps | 99% |
| Alliant Reloder-50ᴾ | <<locked>> | 100% | 46,325 psi | 67% | 2743 fps | 96.9% |
| Baschieri & Pellagri 109 | <<locked>> | 94% | 60,510 psi | 87% | 2838 fps | 99.4% |
| Bofors RP15 | <<locked>> | 94% | 59,132 psi | 85% | 2851 fps | 100% |
| Bofors RP30ᴾ | <<locked>> | 100% | 61,409 psi | 88% | 2910 fps | 100% |
| Bofors RP5 | <<locked>> | 92% | 60,060 psi | 86% | 2861 fps | 100% |
| Bofors RP7 | <<locked>> | 84% | 61,931 psi | 89% | 2776 fps | 100% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 59,785 psi | 86% | 2864 fps | 100% |
| Hodgdon H4350 | <<locked>> | 84% | 59,248 psi | 85% | 2776 fps | 100% |
| Hodgdon H4831 | <<locked>> | 96% | 62,671 psi | 90% | 2854 fps | 100% |
| Hodgdon H4831 SC | <<locked>> | 92% | 62,091 psi | 89% | 2844 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 88% | 61,946 psi | 89% | 2743 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 98% | 60,945 psi | 88% | 2982 fps | 100% |
| Hodgdon Superformance | <<locked>> | 82% | 59,321 psi | 85% | 2828 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,449 psi | 54% | 1709 fps | 100% |
| IMR 4064 | <<locked>> | 82% | 62,874 psi | 90% | 2736 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 82% | 60,858 psi | 87% | 2736 fps | 100% |
| IMR 4350 | <<locked>> | 86% | 60,292 psi | 87% | 2766 fps | 100% |
| IMR 4451 Enduron | <<locked>> | 82% | 59,553 psi | 86% | 2743 fps | 100% |
| IMR 4831 | <<locked>> | 90% | 62,323 psi | 90% | 2782 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 90% | 59,553 psi | 86% | 2785 fps | 100% |
| IMR 7828 SSC | <<locked>> | 92% | 62,337 psi | 90% | 2913 fps | 100% |
| IMR 7977 Enduron | <<locked>> | 98% | 61,815 psi | 89% | 2782 fps | 97.1% |
| IMR 8133 Enduronᴾ | <<locked>> | 100% | 47,718 psi | 69% | 2740 fps | 99.8% |
| Lovex S065 | <<locked>> | 84% | 60,437 psi | 87% | 2740 fps | 100% |
| Lovex S070 | <<locked>> | 86% | 62,453 psi | 90% | 2792 fps | 100% |
| Lovex S071 | <<locked>> | 98% | 61,206 psi | 88% | 2776 fps | 100% |
| Norma 204 | <<locked>> | 86% | 61,989 psi | 89% | 2835 fps | 100% |
| Norma 217ᴾ | <<locked>> | 100% | 48,298 psi | 69% | 2756 fps | 100% |
| Norma MRP | <<locked>> | 90% | 60,205 psi | 86% | 2881 fps | 100% |
| Norma URP | <<locked>> | 86% | 62,569 psi | 90% | 2805 fps | 100% |
| Ramshot Grand | <<locked>> | 88% | 58,262 psi | 84% | 2864 fps | 100% |
| Ramshot Hunter | <<locked>> | 86% | 61,641 psi | 89% | 2822 fps | 100% |
| Ramshot Magnum | <<locked>> | 92% | 59,582 psi | 86% | 2831 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 38,406 psi | 55% | 1752 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 84% | 60,988 psi | 88% | 2802 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 84% | 59,785 psi | 86% | 2835 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 98% | 62,221 psi | 89% | 2976 fps | 100% |
| ReloadSwiss RS 80ᴾ | <<locked>> | 100% | 61,177 psi | 88% | 2953 fps | 100% |
| Rottweil R 904 | <<locked>> | 90% | 62,308 psi | 90% | 2818 fps | 100% |
| Rottweil R 905 | <<locked>> | 90% | 60,814 psi | 87% | 2831 fps | 100% |
| Rottweil R 907 | <<locked>> | 84% | 61,931 psi | 89% | 2776 fps | 100% |
| Shooters World Long Rifle | <<locked>> | 84% | 60,437 psi | 87% | 2740 fps | 100% |
| Shooters World SW4350 | <<locked>> | 86% | 62,453 psi | 90% | 2792 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 82% | 62,424 psi | 90% | 2608 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 84% | 59,379 psi | 85% | 2697 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 90% | 60,394 psi | 87% | 2828 fps | 100% |
| Somchem S361 | <<locked>> | 88% | 60,060 psi | 86% | 2766 fps | 100% |
| Somchem S365 | <<locked>> | 86% | 60,060 psi | 86% | 2756 fps | 100% |
| Somchem S385 | <<locked>> | 90% | 61,003 psi | 88% | 2799 fps | 100% |
| Unknown powder | <<locked>> | 84% | 62,584 psi | 90% | 2805 fps | 100% |
| Vihtavuori N150 | <<locked>> | 86% | 61,380 psi | 88% | 2684 fps | 100% |
| Vihtavuori N160 | <<locked>> | 84% | 62,975 psi | 90% | 2772 fps | 100% |
| Vihtavuori N165 | <<locked>> | 96% | 62,830 psi | 90% | 2805 fps | 100% |
| Vihtavuori N170ᴾ | <<locked>> | 100% | 53,534 psi | 77% | 2730 fps | 97.2% |
| Vihtavuori N550 | <<locked>> | 82% | 59,495 psi | 85% | 2772 fps | 100% |
| Vihtavuori N555 | <<locked>> | 90% | 59,756 psi | 86% | 2789 fps | 100% |
| Vihtavuori N560 | <<locked>> | 92% | 60,481 psi | 87% | 2900 fps | 100% |
| Vihtavuori N565 | <<locked>> | 96% | 60,089 psi | 86% | 2874 fps | 100% |
| Vihtavuori N568ᴾ | <<locked>> | 100% | 61,627 psi | 89% | 2946 fps | 100% |
| Vihtavuori N570ᴾ | <<locked>> | 100% | 59,219 psi | 85% | 2959 fps | 99.2% |
| Winchester 6.5 StaBALL | <<locked>> | 84% | 59,988 psi | 86% | 2700 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 94% | 61,830 psi | 89% | 2907 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 90% | 62,816 psi | 90% | 2822 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% | 58,320 psi | 84% | 2687 fps | 100% |
| Accurate 3100 | <<locked>> | 80% | 39,682 psi | 57% | 2461 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 52,823 psi | 76% | 2674 fps | 100% |
| Accurate MAGPRO | <<locked>> | 80% | 38,972 psi | 56% | 2536 fps | 96.4% |
| ADI APS 450 | <<locked>> | 80% | 59,277 psi | 85% | 2106 fps | 100% |
| ADI AR 2209 | <<locked>> | 80% | 44,193 psi | 63% | 2589 fps | 99.6% |
| ADI AR 2213 | <<locked>> | 80% | 39,392 psi | 57% | 2533 fps | 98.2% |
| ADI AR 2217 | <<locked>> | 82% | 31,256 psi | 45% | 2346 fps | 95.7% |
| ADI AR 2218 | <<locked>> | 94% | 40,306 psi | 58% | 2638 fps | 95.1% |
| ADI AR 2225 | <<locked>> | 80% | 26,527 psi | 38% | 2260 fps | 96.6% |
| Alliant Reloder-16 | <<locked>> | 80% | 50,966 psi | 73% | 2680 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 44,048 psi | 63% | 2582 fps | 99.6% |
| Alliant Reloder-22 | <<locked>> | 80% | 39,929 psi | 57% | 2539 fps | 99.2% |
| Alliant Reloder-23 | <<locked>> | 80% | 38,653 psi | 56% | 2480 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 33,315 psi | 48% | 2428 fps | 99.9% |
| Alliant Reloder-26 | <<locked>> | 80% | 43,337 psi | 62% | 2638 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 92% | 40,727 psi | 59% | 2631 fps | 95.7% |
| Alliant Reloder-50 | <<locked>> | 98% | 42,786 psi | 61% | 2674 fps | 95.9% |
| Baschieri & Pellagri 109 | <<locked>> | 82% | 41,321 psi | 59% | 2513 fps | 95.9% |
| Bofors RP15 | <<locked>> | 80% | 37,101 psi | 53% | 2480 fps | 98.5% |
| Bofors RP30 | <<locked>> | 80% | 30,661 psi | 44% | 2359 fps | 95.8% |
| Bofors RP5 | <<locked>> | 80% | 39,929 psi | 57% | 2539 fps | 99.2% |
| Bofors RP7 | <<locked>> | 80% | 54,476 psi | 78% | 2677 fps | 100% |
| Hodgdon H1000 | <<locked>> | 80% | 29,907 psi | 43% | 2313 fps | 95.7% |
| Hodgdon H4350 | <<locked>> | 80% | 52,112 psi | 75% | 2674 fps | 100% |
| Hodgdon H4831 | <<locked>> | 80% | 37,057 psi | 53% | 2431 fps | 96.9% |
| Hodgdon H4831 SC | <<locked>> | 80% | 41,249 psi | 59% | 2520 fps | 98% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 47,863 psi | 69% | 2562 fps | 100% |
| Hodgdon Retumbo | 82.7 gr | 80% | 32,532 psi | 47% | 2464 fps | 98.2% |
| Hodgdon Superformance | <<locked>> | 80% | 55,056 psi | 79% | 2769 fps | 100% |
| Hodgdon TrailBoss | <<locked>> | 80% | 28,094 psi | 40% | 1529 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 59,219 psi | 85% | 2694 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 80% | 57,217 psi | 82% | 2690 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 49,922 psi | 72% | 2621 fps | 100% |
| IMR 4451 Enduron | <<locked>> | 80% | 56,028 psi | 80% | 2697 fps | 100% |
| IMR 4831 | <<locked>> | 80% | 45,397 psi | 65% | 2552 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 43,381 psi | 62% | 2526 fps | 98.5% |
| IMR 7828 SSC | <<locked>> | 80% | 40,698 psi | 58% | 2572 fps | 98.6% |
| IMR 7977 Enduron | <<locked>> | 94% | 54,404 psi | 78% | 2680 fps | 95.7% |
| IMR 8133 Enduron | <<locked>> | 86% | 29,443 psi | 42% | 2346 fps | 95% |
| Lovex S065 | <<locked>> | 80% | 53,272 psi | 77% | 2644 fps | 100% |
| Lovex S070 | <<locked>> | 80% | 51,706 psi | 74% | 2644 fps | 100% |
| Lovex S071 | <<locked>> | 80% | 34,200 psi | 49% | 2349 fps | 99.5% |
| Norma 204 | <<locked>> | 80% | 50,502 psi | 73% | 2674 fps | 100% |
| Norma 217 | <<locked>> | 82% | 25,657 psi | 37% | 2254 fps | 95.4% |
| Norma MRP | <<locked>> | 80% | 42,250 psi | 61% | 2605 fps | 100% |
| Norma URP | <<locked>> | 80% | 51,517 psi | 74% | 2661 fps | 100% |
| Ramshot Grand | <<locked>> | 80% | 42,685 psi | 61% | 2621 fps | 99.2% |
| Ramshot Hunter | <<locked>> | 80% | 50,488 psi | 73% | 2671 fps | 100% |
| Ramshot Magnum | <<locked>> | 80% | 37,275 psi | 54% | 2487 fps | 99.3% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,747 psi | 41% | 1565 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 53,185 psi | 76% | 2700 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 51,692 psi | 74% | 2726 fps | 100% |
| ReloadSwiss RS 76 | 88.5 gr | 80% | 31,502 psi | 45% | 2438 fps | 98.8% |
| ReloadSwiss RS 80 | <<locked>> | 84% | 33,083 psi | 48% | 2454 fps | 95.2% |
| Rottweil R 904 | <<locked>> | 80% | 45,194 psi | 65% | 2566 fps | 99.2% |
| Rottweil R 905 | <<locked>> | 80% | 43,555 psi | 63% | 2569 fps | 99.6% |
| Rottweil R 907 | <<locked>> | 80% | 54,476 psi | 78% | 2677 fps | 100% |
| Shooters World Long Rifle | <<locked>> | 80% | 53,272 psi | 77% | 2644 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 51,706 psi | 74% | 2644 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 58,784 psi | 84% | 2569 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 52,185 psi | 75% | 2602 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 43,221 psi | 62% | 2566 fps | 99.6% |
| Somchem S361 | <<locked>> | 80% | 45,890 psi | 66% | 2552 fps | 98.8% |
| Somchem S365 | <<locked>> | 80% | 49,124 psi | 71% | 2615 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 43,874 psi | 63% | 2546 fps | 99.9% |
| Unknown powder | <<locked>> | 80% | 54,955 psi | 79% | 2710 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 51,097 psi | 73% | 2552 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 55,158 psi | 79% | 2674 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 37,086 psi | 53% | 2411 fps | 98.9% |
| Vihtavuori N170 | <<locked>> | 96% | 46,992 psi | 68% | 2621 fps | 95.7% |
| Vihtavuori N550 | <<locked>> | 80% | 55,738 psi | 80% | 2723 fps | 100% |
| Vihtavuori N555 | <<locked>> | 80% | 43,004 psi | 62% | 2549 fps | 100% |
| Vihtavuori N560 | 84 gr | 80% | 40,059 psi | 58% | 2562 fps | 97.9% |
| Vihtavuori N565 | <<locked>> | 80% | 34,606 psi | 50% | 2431 fps | 96.5% |
| Vihtavuori N568 | <<locked>> | 84% | 34,577 psi | 50% | 2474 fps | 95.1% |
| Vihtavuori N570 | <<locked>> | 90% | 40,944 psi | 59% | 2644 fps | 95.4% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 52,315 psi | 75% | 2605 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 80% | 36,027 psi | 52% | 2533 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 44,019 psi | 63% | 2552 fps | 99.6% |
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 87 powders for .338 Lapua Mag. Ackley Improved loaded with the .338 | 265gr | CutEdge MTH. Hodgdon Retumbo delivers the highest muzzle velocity at 2,982 fps; across all powders the maximum-charge window runs from 1,709 fps to 2,982 fps. Accurate 8700 gives the best case fill at 100 %, and 87 of the 87 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 265.0 gr projectile in 0.338" calls for a 1:10.0 twist; slower twists will usually not stabilise this weight. Accurate 8700, ADI AR 2217, ADI AR 2218 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 | 265gr | CutEdge MTH they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, Accurate 8700, Ramshot LRT, SNPE Vectan SP 13 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.