Load Specifications
Load data in caliber .338 Lapua Mag. Ackley Improved with .338 | 220gr | Peregrine Glider GRM bullet and 90 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are IMR 7828 SSC, Winchester StaBALL HD 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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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>> | 84% | 61,511 psi | 88% | 2976 fps | 100% |
| Accurate 3100 | <<locked>> | 96% | 61,888 psi | 89% | 3038 fps | 100% |
| Accurate 4350 | <<locked>> | 86% | 58,813 psi | 84% | 3015 fps | 100% |
| Accurate MAGPRO | <<locked>> | 96% | 61,917 psi | 89% | 3169 fps | 99.3% |
| ADI APS 450 | <<locked>> | 82% | 61,076 psi | 88% | 2343 fps | 100% |
| ADI AR 2208 | <<locked>> | 84% | 62,990 psi | 90% | 3015 fps | 100% |
| ADI AR 2209 | <<locked>> | 92% | 60,002 psi | 86% | 3087 fps | 100% |
| ADI AR 2213 | <<locked>> | 96% | 62,134 psi | 89% | 3159 fps | 99.9% |
| ADI AR 2217ᴾ | <<locked>> | 100% | 51,953 psi | 75% | 2995 fps | 99.4% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 46,499 psi | 67% | 2959 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 82% | 60,843 psi | 87% | 2986 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 88% | 60,060 psi | 86% | 3074 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 84% | 61,569 psi | 88% | 3084 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 92% | 59,422 psi | 85% | 3074 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 96% | 61,989 psi | 89% | 3146 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 96% | 59,205 psi | 85% | 3045 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 59,030 psi | 85% | 3117 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 92% | 60,408 psi | 87% | 3146 fps | 100% |
| Baschieri & Pellagri 109 | <<locked>> | 96% | 59,248 psi | 85% | 3054 fps | 98.2% |
| Bofors RP15 | <<locked>> | 98% | 60,843 psi | 87% | 3130 fps | 100% |
| Bofors RP3 | <<locked>> | 82% | 62,250 psi | 89% | 3005 fps | 100% |
| Bofors RP30ᴾ | <<locked>> | 100% | 54,723 psi | 79% | 3071 fps | 99.7% |
| Bofors RP5 | <<locked>> | 96% | 61,989 psi | 89% | 3146 fps | 100% |
| Bofors RP7 | <<locked>> | 86% | 60,785 psi | 87% | 3018 fps | 100% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 53,447 psi | 77% | 3022 fps | 99.8% |
| Hodgdon H380 | <<locked>> | 82% | 62,120 psi | 89% | 3031 fps | 100% |
| Hodgdon H414 | <<locked>> | 84% | 61,917 psi | 89% | 3094 fps | 100% |
| Hodgdon H4350 | <<locked>> | 88% | 61,583 psi | 88% | 3064 fps | 100% |
| Hodgdon H4831 | <<locked>> | 98% | 60,945 psi | 88% | 3077 fps | 99.6% |
| Hodgdon H4831 SC | <<locked>> | 94% | 60,379 psi | 87% | 3071 fps | 99.5% |
| Hodgdon Hybrid 100V | <<locked>> | 90% | 60,249 psi | 87% | 2986 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 57,899 psi | 83% | 3205 fps | 100% |
| Hodgdon Superformance | <<locked>> | 86% | 62,120 psi | 89% | 3123 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,101 psi | 53% | 1880 fps | 100% |
| Hodgdon VARGET | <<locked>> | 82% | 62,511 psi | 90% | 3002 fps | 100% |
| IMR 4064 | <<locked>> | 84% | 61,960 psi | 89% | 2992 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 84% | 60,191 psi | 86% | 2986 fps | 100% |
| IMR 4350 | <<locked>> | 90% | 62,903 psi | 90% | 3058 fps | 100% |
| IMR 4451 Enduron | <<locked>> | 86% | 62,366 psi | 90% | 3038 fps | 100% |
| IMR 4831 | <<locked>> | 92% | 60,524 psi | 87% | 3022 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 94% | 62,163 psi | 89% | 3068 fps | 99.7% |
| IMR 7828 SSC | <<locked>> | 94% | 60,220 psi | 87% | 3140 fps | 99.9% |
| IMR 8133 Enduronᴾ | <<locked>> | 100% | 41,742 psi | 60% | 2854 fps | 97.7% |
| Lovex S062 | <<locked>> | 82% | 62,714 psi | 90% | 2979 fps | 100% |
| Lovex S065 | <<locked>> | 88% | 62,990 psi | 90% | 3028 fps | 100% |
| Lovex S070 | <<locked>> | 88% | 61,308 psi | 88% | 3035 fps | 100% |
| Lovex S071ᴾ | <<locked>> | 100% | 58,813 psi | 84% | 2999 fps | 100% |
| Norma 204 | <<locked>> | 88% | 60,611 psi | 87% | 3071 fps | 100% |
| Norma 217ᴾ | <<locked>> | 100% | 41,959 psi | 60% | 2881 fps | 99.4% |
| Norma MRP | <<locked>> | 94% | 62,207 psi | 89% | 3166 fps | 100% |
| Norma URP | <<locked>> | 88% | 61,119 psi | 88% | 3051 fps | 100% |
| Ramshot Grand | <<locked>> | 92% | 60,437 psi | 87% | 3150 fps | 100% |
| Ramshot Hunter | <<locked>> | 88% | 60,089 psi | 86% | 3064 fps | 100% |
| Ramshot Magnum | <<locked>> | 96% | 62,091 psi | 89% | 3117 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,927 psi | 54% | 1926 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 82% | 61,801 psi | 89% | 3025 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 82% | 61,119 psi | 88% | 3064 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 86% | 59,248 psi | 85% | 3041 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 88% | 62,033 psi | 89% | 3130 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 59,176 psi | 85% | 3202 fps | 100% |
| ReloadSwiss RS 80ᴾ | <<locked>> | 100% | 53,766 psi | 77% | 3091 fps | 98.9% |
| Rottweil R 903 | <<locked>> | 84% | 62,482 psi | 90% | 3002 fps | 100% |
| Rottweil R 904 | <<locked>> | 92% | 60,959 psi | 88% | 3051 fps | 99.8% |
| Rottweil R 905 | <<locked>> | 92% | 58,900 psi | 85% | 3061 fps | 100% |
| Rottweil R 907 | <<locked>> | 86% | 60,785 psi | 87% | 3018 fps | 100% |
| Shooters World Long Rifle | <<locked>> | 88% | 62,990 psi | 90% | 3028 fps | 100% |
| Shooters World Precision | <<locked>> | 82% | 62,714 psi | 90% | 2979 fps | 100% |
| Shooters World SW4350 | <<locked>> | 88% | 61,308 psi | 88% | 3035 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 82% | 60,394 psi | 87% | 3015 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 84% | 61,801 psi | 89% | 2861 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 88% | 62,569 psi | 90% | 2989 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 94% | 62,642 psi | 90% | 3117 fps | 100% |
| Somchem S355 | <<locked>> | 84% | 61,786 psi | 89% | 2995 fps | 100% |
| Somchem S361 | <<locked>> | 92% | 62,859 psi | 90% | 3045 fps | 99.7% |
| Somchem S365 | <<locked>> | 90% | 62,033 psi | 89% | 3048 fps | 100% |
| Somchem S385 | <<locked>> | 92% | 59,422 psi | 85% | 3031 fps | 100% |
| Unknown powder | <<locked>> | 86% | 61,163 psi | 88% | 3054 fps | 100% |
| Vihtavuori N150 | <<locked>> | 88% | 60,089 psi | 86% | 2927 fps | 100% |
| Vihtavuori N160 | <<locked>> | 86% | 61,554 psi | 88% | 3015 fps | 100% |
| Vihtavuori N165 | <<locked>> | 98% | 61,003 psi | 88% | 3035 fps | 100% |
| Vihtavuori N550 | <<locked>> | 86% | 62,047 psi | 89% | 3068 fps | 100% |
| Vihtavuori N555 | <<locked>> | 94% | 61,438 psi | 88% | 3074 fps | 100% |
| Vihtavuori N560 | <<locked>> | 96% | 62,424 psi | 90% | 3182 fps | 99.8% |
| Vihtavuori N565ᴾ | <<locked>> | 100% | 61,714 psi | 89% | 3150 fps | 99.9% |
| Vihtavuori N568ᴾ | <<locked>> | 100% | 54,563 psi | 78% | 3091 fps | 98.6% |
| Vihtavuori N570ᴾ | <<locked>> | 100% | 52,083 psi | 75% | 3084 fps | 96.5% |
| Winchester 6.5 StaBALL | <<locked>> | 86% | 58,827 psi | 85% | 2940 fps | 100% |
| Winchester 760 | <<locked>> | 84% | 61,917 psi | 89% | 3094 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 98% | 62,743 psi | 90% | 3196 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 92% | 61,482 psi | 88% | 3054 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% | 53,838 psi | 77% | 2867 fps | 99.9% |
| Accurate 3100 | <<locked>> | 80% | 35,534 psi | 51% | 2595 fps | 98.7% |
| Accurate 4350 | <<locked>> | 80% | 47,805 psi | 69% | 2848 fps | 100% |
| Accurate MAGPRO | <<locked>> | 86% | 43,221 psi | 62% | 2844 fps | 95.7% |
| ADI APS 450 | <<locked>> | 80% | 59,103 psi | 85% | 2313 fps | 100% |
| ADI AR 2208 | <<locked>> | 80% | 55,767 psi | 80% | 2917 fps | 100% |
| ADI AR 2209 | <<locked>> | 80% | 39,856 psi | 57% | 2733 fps | 97.6% |
| ADI AR 2213 | <<locked>> | 82% | 38,101 psi | 55% | 2723 fps | 95.8% |
| ADI AR 2217 | <<locked>> | 90% | 36,854 psi | 53% | 2687 fps | 95.7% |
| ADI AR 2225 | <<locked>> | 86% | 28,935 psi | 42% | 2520 fps | 95.4% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 57,145 psi | 82% | 2936 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 45,919 psi | 66% | 2858 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 80% | 53,432 psi | 77% | 2976 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 39,943 psi | 57% | 2726 fps | 97.7% |
| Alliant Reloder-22 | <<locked>> | 80% | 35,650 psi | 51% | 2667 fps | 96.5% |
| Alliant Reloder-23 | <<locked>> | 80% | 34,330 psi | 49% | 2625 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 29,689 psi | 43% | 2536 fps | 97.6% |
| Alliant Reloder-26 | <<locked>> | 80% | 37,956 psi | 55% | 2772 fps | 99.9% |
| Baschieri & Pellagri 109 | <<locked>> | 88% | 45,977 psi | 66% | 2818 fps | 95.1% |
| Bofors RP15 | <<locked>> | 80% | 33,098 psi | 48% | 2598 fps | 95.3% |
| Bofors RP3 | <<locked>> | 80% | 58,175 psi | 84% | 2953 fps | 100% |
| Bofors RP30 | <<locked>> | 88% | 35,897 psi | 52% | 2700 fps | 95.9% |
| Bofors RP5 | <<locked>> | 80% | 35,650 psi | 51% | 2667 fps | 96.5% |
| Bofors RP7 | <<locked>> | 80% | 50,227 psi | 72% | 2854 fps | 99.8% |
| Hodgdon H1000 | <<locked>> | 88% | 35,404 psi | 51% | 2654 fps | 95.9% |
| Hodgdon H380 | <<locked>> | 80% | 58,291 psi | 84% | 2979 fps | 100% |
| Hodgdon H414 | <<locked>> | 80% | 53,838 psi | 77% | 2976 fps | 100% |
| Hodgdon H4350 | <<locked>> | 80% | 47,776 psi | 69% | 2844 fps | 99.3% |
| Hodgdon H4831 | <<locked>> | 84% | 38,232 psi | 55% | 2671 fps | 95.2% |
| Hodgdon H4831 SC | <<locked>> | 82% | 40,001 psi | 57% | 2710 fps | 95.8% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 43,265 psi | 62% | 2736 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 82% | 31,024 psi | 45% | 2618 fps | 95% |
| Hodgdon Superformance | <<locked>> | 80% | 49,530 psi | 71% | 2933 fps | 99.9% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,804 psi | 40% | 1686 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 58,711 psi | 84% | 2953 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 54,723 psi | 79% | 2890 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 80% | 53,113 psi | 76% | 2881 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 45,672 psi | 66% | 2785 fps | 99.4% |
| IMR 4451 Enduron | <<locked>> | 80% | 51,793 psi | 74% | 2881 fps | 100% |
| IMR 4831 | <<locked>> | 80% | 41,133 psi | 59% | 2713 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 39,624 psi | 57% | 2667 fps | 95.9% |
| IMR 7828 SSC | 88.3 gr | 80% | 36,376 psi | 52% | 2690 fps | 95.3% |
| IMR 8133 Enduron | <<locked>> | 96% | 36,361 psi | 52% | 2733 fps | 95.9% |
| Lovex S062 | <<locked>> | 80% | 58,929 psi | 85% | 2933 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 49,081 psi | 71% | 2825 fps | 100% |
| Lovex S070 | <<locked>> | 80% | 47,369 psi | 68% | 2818 fps | 99.8% |
| Lovex S071 | <<locked>> | 80% | 30,414 psi | 44% | 2467 fps | 97.1% |
| Norma 204 | <<locked>> | 80% | 45,948 psi | 66% | 2831 fps | 98.8% |
| Norma 217 | <<locked>> | 90% | 29,660 psi | 43% | 2572 fps | 95.2% |
| Norma MRP | <<locked>> | 80% | 37,449 psi | 54% | 2736 fps | 98.4% |
| Norma URP | <<locked>> | 80% | 46,804 psi | 67% | 2838 fps | 100% |
| Ramshot Grand | <<locked>> | 80% | 37,826 psi | 54% | 2740 fps | 96.3% |
| Ramshot Hunter | <<locked>> | 80% | 45,803 psi | 66% | 2838 fps | 99.9% |
| Ramshot Magnum | <<locked>> | 80% | 32,837 psi | 47% | 2592 fps | 96.4% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,355 psi | 41% | 1722 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 57,754 psi | 83% | 2969 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 56,971 psi | 82% | 3015 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 47,935 psi | 69% | 2871 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 46,311 psi | 67% | 2897 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 82% | 30,023 psi | 43% | 2585 fps | 95.9% |
| ReloadSwiss RS 80 | <<locked>> | 92% | 39,305 psi | 56% | 2812 fps | 95.4% |
| Rottweil R 903 | <<locked>> | 80% | 54,708 psi | 79% | 2900 fps | 100% |
| Rottweil R 904 | <<locked>> | 80% | 41,205 psi | 59% | 2710 fps | 96.9% |
| Rottweil R 905 | <<locked>> | 80% | 39,160 psi | 56% | 2710 fps | 97.6% |
| Rottweil R 907 | <<locked>> | 80% | 50,227 psi | 72% | 2854 fps | 99.8% |
| Shooters World Long Rifle | <<locked>> | 80% | 49,081 psi | 71% | 2825 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 58,929 psi | 85% | 2933 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 47,369 psi | 68% | 2818 fps | 99.8% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 56,550 psi | 81% | 2966 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 54,549 psi | 78% | 2769 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 48,066 psi | 69% | 2772 fps | 99.8% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 38,841 psi | 56% | 2707 fps | 97.5% |
| Somchem S355 | <<locked>> | 80% | 54,476 psi | 78% | 2897 fps | 100% |
| Somchem S361 | <<locked>> | 80% | 41,887 psi | 60% | 2697 fps | 96.4% |
| Somchem S365 | <<locked>> | 80% | 43,976 psi | 63% | 2789 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 39,668 psi | 57% | 2690 fps | 98.4% |
| Unknown powder | <<locked>> | 80% | 50,212 psi | 72% | 2894 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 46,833 psi | 67% | 2740 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 50,401 psi | 72% | 2858 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 33,330 psi | 48% | 2536 fps | 96.2% |
| Vihtavuori N550 | <<locked>> | 80% | 51,010 psi | 73% | 2907 fps | 100% |
| Vihtavuori N555 | <<locked>> | 80% | 38,450 psi | 55% | 2700 fps | 100% |
| Vihtavuori N560 | 90 gr | 82% | 38,305 psi | 55% | 2746 fps | 95.5% |
| Vihtavuori N565 | <<locked>> | 86% | 37,797 psi | 54% | 2717 fps | 95.6% |
| Vihtavuori N568 | <<locked>> | 92% | 40,683 psi | 58% | 2828 fps | 95.2% |
| Vihtavuori N570 | <<locked>> | 98% | 48,472 psi | 70% | 3018 fps | 95.5% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 47,572 psi | 68% | 2782 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 53,838 psi | 77% | 2976 fps | 100% |
| Winchester StaBALL HD | 88.8 gr | 80% | 30,632 psi | 44% | 2654 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 39,726 psi | 57% | 2690 fps | 97.7% |
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 97 powders for .338 Lapua Mag. Ackley Improved loaded with the .338 | 220gr | Peregrine Glider GRM. Hodgdon Retumbo delivers the highest muzzle velocity at 3,205 fps; across all powders the maximum-charge window runs from 1,880 fps to 3,205 fps. ADI AR 2217 gives the best case fill at 100 %, and 97 of the 97 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (480 MPa), the top charges use 53–90 %, leaving at least 10 % headroom. The 220.0 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. IMR 7828 SSC, Winchester StaBALL HD, Vihtavuori N560 rank at the top here: for .338 Lapua Mag. Ackley Improved with the .338 | 220gr | Peregrine Glider GRM they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, ADI AR 2218, Alliant Reloder-50, IMR 7977 Enduron 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.