Load Specifications
Load data in caliber .338 Lapua Mag. Ackley Improved with .338 | 225gr | Frontier BTSP bullet and 84 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Vihtavuori N560, Accurate MAGPRO and Norma MRP.
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 2700 | <<locked>> | 82% | 59,567 psi | 86% | 2917 fps | 100% |
| Accurate 3100 | <<locked>> | 94% | 60,365 psi | 87% | 2986 fps | 100% |
| Accurate 4350 | <<locked>> | 86% | 61,380 psi | 88% | 3012 fps | 100% |
| Accurate MAGPRO | <<locked>> | 94% | 60,089 psi | 86% | 3110 fps | 99.2% |
| ADI APS 450 | <<locked>> | 82% | 61,163 psi | 88% | 2320 fps | 100% |
| ADI AR 2208 | <<locked>> | 82% | 60,945 psi | 88% | 2956 fps | 100% |
| ADI AR 2209 | <<locked>> | 92% | 62,120 psi | 89% | 3081 fps | 100% |
| ADI AR 2213 | <<locked>> | 94% | 60,104 psi | 86% | 3097 fps | 99.9% |
| ADI AR 2217ᴾ | <<locked>> | 100% | 54,157 psi | 78% | 3002 fps | 99.7% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 48,776 psi | 70% | 2969 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 82% | 62,903 psi | 90% | 2979 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 88% | 62,236 psi | 89% | 3064 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 82% | 59,524 psi | 86% | 3022 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 92% | 61,554 psi | 88% | 3071 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 94% | 60,263 psi | 87% | 3091 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 96% | 61,685 psi | 89% | 3038 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 61,598 psi | 88% | 3114 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 90% | 58,813 psi | 84% | 3091 fps | 100% |
| Alliant Reloder-33ᴾ | <<locked>> | 100% | 51,068 psi | 73% | 3025 fps | 96.9% |
| Baschieri & Pellagri 109 | <<locked>> | 96% | 61,032 psi | 88% | 3054 fps | 98.6% |
| Bofors RP15 | <<locked>> | 96% | 59,364 psi | 85% | 3074 fps | 100% |
| Bofors RP30ᴾ | <<locked>> | 100% | 57,348 psi | 82% | 3077 fps | 99.9% |
| Bofors RP5 | <<locked>> | 94% | 60,263 psi | 87% | 3091 fps | 100% |
| Bofors RP7 | <<locked>> | 86% | 62,758 psi | 90% | 3009 fps | 100% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 55,724 psi | 80% | 3025 fps | 100% |
| Hodgdon H414 | <<locked>> | 82% | 59,901 psi | 86% | 3031 fps | 100% |
| Hodgdon H4350 | <<locked>> | 86% | 59,741 psi | 86% | 3005 fps | 100% |
| Hodgdon H4831 | <<locked>> | 96% | 59,190 psi | 85% | 3022 fps | 99.6% |
| Hodgdon H4831 SC | <<locked>> | 94% | 62,540 psi | 90% | 3068 fps | 99.8% |
| Hodgdon Hybrid 100V | <<locked>> | 90% | 62,482 psi | 90% | 2979 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 60,481 psi | 87% | 3209 fps | 100% |
| Hodgdon Superformance | <<locked>> | 84% | 59,901 psi | 86% | 3058 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,318 psi | 54% | 1864 fps | 100% |
| IMR 4064 | <<locked>> | 82% | 59,973 psi | 86% | 2930 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 84% | 61,888 psi | 89% | 2976 fps | 100% |
| IMR 4350 | <<locked>> | 88% | 61,061 psi | 88% | 2999 fps | 100% |
| IMR 4451 Enduron | <<locked>> | 84% | 60,379 psi | 87% | 2979 fps | 100% |
| IMR 4831 | <<locked>> | 92% | 62,801 psi | 90% | 3015 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 92% | 60,147 psi | 86% | 3005 fps | 99.7% |
| IMR 7828 SSC | <<locked>> | 94% | 62,598 psi | 90% | 3140 fps | 100% |
| IMR 8133 Enduronᴾ | <<locked>> | 100% | 44,179 psi | 63% | 2874 fps | 98.4% |
| Lovex S065 | <<locked>> | 86% | 61,279 psi | 88% | 2972 fps | 100% |
| Lovex S070 | <<locked>> | 86% | 59,538 psi | 86% | 2976 fps | 100% |
| Lovex S071ᴾ | <<locked>> | 100% | 61,511 psi | 88% | 2999 fps | 100% |
| Norma 204 | <<locked>> | 88% | 62,729 psi | 90% | 3068 fps | 100% |
| Norma 217ᴾ | <<locked>> | 100% | 44,570 psi | 64% | 2900 fps | 99.8% |
| Norma MRP | <<locked>> | 92% | 60,568 psi | 87% | 3110 fps | 100% |
| Norma URP | <<locked>> | 86% | 59,292 psi | 85% | 2992 fps | 100% |
| Ramshot Grand | <<locked>> | 90% | 58,450 psi | 84% | 3087 fps | 99.9% |
| Ramshot Hunter | <<locked>> | 88% | 62,265 psi | 89% | 3058 fps | 100% |
| Ramshot Magnum | <<locked>> | 94% | 59,872 psi | 86% | 3054 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 38,203 psi | 55% | 1906 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 86% | 61,656 psi | 89% | 3038 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 86% | 60,162 psi | 86% | 3071 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 62,004 psi | 89% | 3205 fps | 100% |
| ReloadSwiss RS 80ᴾ | <<locked>> | 100% | 56,637 psi | 81% | 3104 fps | 99.4% |
| Rottweil R 903 | <<locked>> | 82% | 60,872 psi | 87% | 2946 fps | 100% |
| Rottweil R 904 | <<locked>> | 92% | 62,975 psi | 90% | 3048 fps | 99.9% |
| Rottweil R 905 | <<locked>> | 92% | 61,221 psi | 88% | 3061 fps | 100% |
| Rottweil R 907 | <<locked>> | 86% | 62,758 psi | 90% | 3009 fps | 100% |
| Shooters World Long Rifle | <<locked>> | 86% | 61,279 psi | 88% | 2972 fps | 100% |
| Shooters World SW4350 | <<locked>> | 86% | 59,538 psi | 86% | 2976 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 82% | 62,453 psi | 90% | 3009 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 82% | 59,698 psi | 86% | 2802 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 86% | 60,481 psi | 87% | 2930 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 92% | 60,771 psi | 87% | 3058 fps | 100% |
| Somchem S355 | <<locked>> | 82% | 60,104 psi | 86% | 2940 fps | 100% |
| Somchem S361 | <<locked>> | 90% | 60,814 psi | 87% | 2986 fps | 99.6% |
| Somchem S365 | <<locked>> | 88% | 60,495 psi | 87% | 2992 fps | 100% |
| Somchem S385 | <<locked>> | 92% | 61,757 psi | 89% | 3028 fps | 100% |
| Unknown powder | <<locked>> | 84% | 59,437 psi | 85% | 2995 fps | 100% |
| Vihtavuori N150 | <<locked>> | 88% | 62,105 psi | 89% | 2917 fps | 100% |
| Vihtavuori N160 | <<locked>> | 84% | 59,669 psi | 86% | 2956 fps | 100% |
| Vihtavuori N165 | <<locked>> | 96% | 59,393 psi | 85% | 2979 fps | 100% |
| Vihtavuori N550 | <<locked>> | 84% | 60,249 psi | 87% | 3009 fps | 100% |
| Vihtavuori N555 | <<locked>> | 92% | 59,988 psi | 86% | 3018 fps | 100% |
| Vihtavuori N560 | <<locked>> | 94% | 60,640 psi | 87% | 3127 fps | 99.8% |
| Vihtavuori N565 | <<locked>> | 98% | 60,292 psi | 87% | 3097 fps | 99.8% |
| Vihtavuori N568ᴾ | <<locked>> | 100% | 57,232 psi | 82% | 3100 fps | 99.1% |
| Vihtavuori N570ᴾ | <<locked>> | 100% | 54,737 psi | 79% | 3100 fps | 97.3% |
| Winchester 6.5 StaBALL | <<locked>> | 86% | 60,887 psi | 87% | 2930 fps | 100% |
| Winchester 760 | <<locked>> | 82% | 59,901 psi | 86% | 3031 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 96% | 61,061 psi | 88% | 3136 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 90% | 59,350 psi | 85% | 2992 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% | 55,709 psi | 80% | 2861 fps | 100% |
| Accurate 3100 | <<locked>> | 80% | 37,753 psi | 54% | 2612 fps | 99.3% |
| Accurate 4350 | <<locked>> | 80% | 50,169 psi | 72% | 2854 fps | 100% |
| Accurate MAGPRO | 96 gr | 84% | 42,264 psi | 61% | 2795 fps | 95.7% |
| ADI APS 450 | <<locked>> | 80% | 59,190 psi | 85% | 2290 fps | 100% |
| ADI AR 2208 | <<locked>> | 80% | 57,464 psi | 83% | 2907 fps | 100% |
| ADI AR 2209 | <<locked>> | 80% | 41,640 psi | 60% | 2740 fps | 98.3% |
| ADI AR 2213 | <<locked>> | 80% | 37,202 psi | 53% | 2671 fps | 95.8% |
| ADI AR 2217 | <<locked>> | 88% | 36,230 psi | 52% | 2644 fps | 95.8% |
| ADI AR 2225 | <<locked>> | 84% | 28,776 psi | 41% | 2487 fps | 95.7% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 59,132 psi | 85% | 2930 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 47,848 psi | 69% | 2858 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 80% | 55,622 psi | 80% | 2969 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 41,727 psi | 60% | 2736 fps | 98.3% |
| Alliant Reloder-22 | <<locked>> | 80% | 37,579 psi | 54% | 2680 fps | 97.4% |
| Alliant Reloder-23 | <<locked>> | 80% | 36,289 psi | 52% | 2635 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 31,415 psi | 45% | 2559 fps | 98.5% |
| Alliant Reloder-26 | <<locked>> | 80% | 40,292 psi | 58% | 2789 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 98% | 47,456 psi | 68% | 2956 fps | 96% |
| Baschieri & Pellagri 109 | <<locked>> | 86% | 44,759 psi | 64% | 2766 fps | 95.1% |
| Bofors RP15 | <<locked>> | 80% | 34,954 psi | 50% | 2615 fps | 96.4% |
| Bofors RP30 | <<locked>> | 84% | 33,141 psi | 48% | 2598 fps | 95% |
| Bofors RP5 | <<locked>> | 80% | 37,579 psi | 54% | 2680 fps | 97.4% |
| Bofors RP7 | <<locked>> | 80% | 52,083 psi | 75% | 2851 fps | 99.9% |
| Hodgdon H1000 | <<locked>> | 86% | 34,722 psi | 50% | 2608 fps | 95.9% |
| Hodgdon H414 | <<locked>> | 80% | 55,927 psi | 80% | 2976 fps | 100% |
| Hodgdon H4350 | <<locked>> | 80% | 49,559 psi | 71% | 2844 fps | 99.6% |
| Hodgdon H4831 | <<locked>> | 82% | 37,420 psi | 54% | 2625 fps | 95.2% |
| Hodgdon H4831 SC | <<locked>> | 80% | 39,015 psi | 56% | 2661 fps | 95.8% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 45,208 psi | 65% | 2736 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 80% | 30,661 psi | 44% | 2575 fps | 95.1% |
| Hodgdon Superformance | <<locked>> | 80% | 51,677 psi | 74% | 2936 fps | 100% |
| Hodgdon TrailBoss | <<locked>> | 80% | 28,036 psi | 40% | 1670 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 56,478 psi | 81% | 2881 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 80% | 54,723 psi | 79% | 2874 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 47,427 psi | 68% | 2789 fps | 99.7% |
| IMR 4451 Enduron | <<locked>> | 80% | 53,432 psi | 77% | 2874 fps | 100% |
| IMR 4831 | <<locked>> | 80% | 43,105 psi | 62% | 2717 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 41,249 psi | 59% | 2674 fps | 96.6% |
| IMR 7828 SSC | <<locked>> | 80% | 38,218 psi | 55% | 2707 fps | 96.3% |
| IMR 8133 Enduron | <<locked>> | 92% | 33,779 psi | 49% | 2638 fps | 95% |
| Lovex S065 | <<locked>> | 80% | 50,966 psi | 73% | 2822 fps | 100% |
| Lovex S070 | <<locked>> | 80% | 49,298 psi | 71% | 2818 fps | 100% |
| Lovex S071 | <<locked>> | 80% | 32,474 psi | 47% | 2487 fps | 98.1% |
| Norma 204 | <<locked>> | 80% | 47,819 psi | 69% | 2835 fps | 99.2% |
| Norma 217 | <<locked>> | 88% | 29,602 psi | 43% | 2539 fps | 95.5% |
| Norma MRP | 89.7 gr | 80% | 39,523 psi | 57% | 2753 fps | 99% |
| Norma URP | <<locked>> | 80% | 48,791 psi | 70% | 2835 fps | 100% |
| Ramshot Grand | <<locked>> | 80% | 39,842 psi | 57% | 2759 fps | 97.3% |
| Ramshot Hunter | <<locked>> | 80% | 47,761 psi | 69% | 2841 fps | 100% |
| Ramshot Magnum | <<locked>> | 80% | 34,795 psi | 50% | 2612 fps | 97.4% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,631 psi | 41% | 1706 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 50,183 psi | 72% | 2874 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 48,414 psi | 70% | 2900 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 80% | 29,704 psi | 43% | 2549 fps | 96.1% |
| ReloadSwiss RS 80 | <<locked>> | 90% | 38,595 psi | 55% | 2766 fps | 95.5% |
| Rottweil R 903 | <<locked>> | 80% | 56,956 psi | 82% | 2897 fps | 100% |
| Rottweil R 904 | <<locked>> | 80% | 42,946 psi | 62% | 2717 fps | 97.6% |
| Rottweil R 905 | <<locked>> | 80% | 41,104 psi | 59% | 2720 fps | 98.3% |
| Rottweil R 907 | <<locked>> | 80% | 52,083 psi | 75% | 2851 fps | 99.9% |
| Shooters World Long Rifle | <<locked>> | 80% | 50,966 psi | 73% | 2822 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 49,298 psi | 71% | 2818 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 58,552 psi | 84% | 2956 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 56,217 psi | 81% | 2756 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 49,966 psi | 72% | 2776 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 40,770 psi | 59% | 2717 fps | 98.2% |
| Somchem S355 | <<locked>> | 80% | 56,463 psi | 81% | 2890 fps | 100% |
| Somchem S361 | <<locked>> | 80% | 43,671 psi | 63% | 2703 fps | 97.1% |
| Somchem S365 | <<locked>> | 80% | 46,180 psi | 66% | 2792 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 41,626 psi | 60% | 2700 fps | 99% |
| Unknown powder | <<locked>> | 80% | 52,156 psi | 75% | 2890 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 48,704 psi | 70% | 2733 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 52,417 psi | 75% | 2854 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 35,085 psi | 50% | 2549 fps | 97.1% |
| Vihtavuori N550 | <<locked>> | 80% | 53,069 psi | 76% | 2907 fps | 100% |
| Vihtavuori N555 | <<locked>> | 80% | 40,654 psi | 58% | 2710 fps | 100% |
| Vihtavuori N560 | 87.9 gr | 80% | 37,695 psi | 54% | 2700 fps | 95.5% |
| Vihtavuori N565 | <<locked>> | 84% | 37,391 psi | 54% | 2677 fps | 95.8% |
| Vihtavuori N568 | <<locked>> | 90% | 40,089 psi | 58% | 2785 fps | 95.3% |
| Vihtavuori N570 | <<locked>> | 96% | 47,413 psi | 68% | 2966 fps | 95.5% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 49,443 psi | 71% | 2779 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 55,927 psi | 80% | 2976 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 80% | 32,953 psi | 47% | 2677 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 41,640 psi | 60% | 2700 fps | 98.3% |
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 90 powders for .338 Lapua Mag. Ackley Improved loaded with the .338 | 225gr | Frontier BTSP. Hodgdon Retumbo delivers the highest muzzle velocity at 3,209 fps; across all powders the maximum-charge window runs from 1,864 fps to 3,209 fps. ADI AR 2217 gives the best case fill at 100 %, and 90 of the 90 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 225.0 gr projectile in 0.338" calls for a 1:11.0 twist; slower twists will usually not stabilise this weight. ADI AR 2217, 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 N560, Accurate MAGPRO, Norma MRP rank at the top here: for .338 Lapua Mag. Ackley Improved with the .338 | 225gr | Frontier BTSP they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, Alliant Reloder-50, Lovex D100, Shooters World 50 BMG 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.