Load Specifications
Load data in caliber .338 Lapua Mag. with .338 | 185gr | Hornady ECX bullet and 77 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Alliant Reloder-26, Norma MRP and ReloadSwiss RS 70.
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: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2700 | <<locked>> | 82% | 53,563 psi | 88% | 2953 fps | 98% |
| Accurate 3100 | <<locked>> | 98% | 51,982 psi | 85% | 2992 fps | 99.1% |
| Accurate 4064 | <<locked>> | 82% | 53,055 psi | 87% | 2953 fps | 100% |
| Accurate 4350 | <<locked>> | 90% | 53,824 psi | 88% | 3051 fps | 99.9% |
| ADI AR 2208 | <<locked>> | 84% | 53,069 psi | 87% | 2982 fps | 100% |
| ADI AR 2209 | <<locked>> | 96% | 54,969 psi | 90% | 3094 fps | 97.6% |
| Alliant Power Pro Varmint | <<locked>> | 96% | 55,114 psi | 90% | 3091 fps | 97.7% |
| Alliant Reloder- TS 15.5 | <<locked>> | 84% | 53,940 psi | 89% | 3009 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 82% | 53,940 psi | 89% | 3025 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 92% | 54,708 psi | 90% | 3117 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 86% | 52,083 psi | 86% | 3077 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 96% | 54,375 psi | 89% | 3081 fps | 97.6% |
| Alliant Reloder-22 | <<locked>> | 98% | 51,866 psi | 85% | 3077 fps | 97.3% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 52,417 psi | 86% | 3071 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 45,585 psi | 75% | 2989 fps | 98.9% |
| Alliant Reloder-26 | <<locked>> | 96% | 52,431 psi | 86% | 3150 fps | 99.9% |
| Bofors RP15ᴾ | <<locked>> | 100% | 50,705 psi | 83% | 3054 fps | 96.9% |
| Bofors RP3 | <<locked>> | 84% | 54,737 psi | 90% | 3022 fps | 100% |
| Bofors RP5 | <<locked>> | 98% | 51,866 psi | 85% | 3077 fps | 97.3% |
| Bofors RP7 | <<locked>> | 88% | 54,128 psi | 89% | 3002 fps | 98.3% |
| Hodgdon H380 | <<locked>> | 84% | 55,114 psi | 90% | 3035 fps | 99.8% |
| Hodgdon H414 | <<locked>> | 88% | 52,402 psi | 86% | 3045 fps | 98.6% |
| Hodgdon H4350 | <<locked>> | 86% | 52,272 psi | 86% | 3005 fps | 97.4% |
| Hodgdon Hybrid 100V | <<locked>> | 92% | 51,576 psi | 85% | 2982 fps | 100% |
| Hodgdon Superformance | <<locked>> | 88% | 52,489 psi | 86% | 3074 fps | 98.4% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,463 psi | 60% | 1936 fps | 100% |
| IMR 4064 | <<locked>> | 82% | 52,431 psi | 86% | 2963 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 82% | 54,882 psi | 90% | 2995 fps | 98.8% |
| IMR 4350 | <<locked>> | 90% | 51,895 psi | 85% | 2979 fps | 98% |
| IMR 4451 Enduron | <<locked>> | 86% | 52,286 psi | 86% | 2972 fps | 98.4% |
| IMR 4831 | <<locked>> | 92% | 54,375 psi | 89% | 3045 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 96% | 54,447 psi | 89% | 3018 fps | 95.8% |
| IMR 7828 SSCᴾ | <<locked>> | 100% | 53,766 psi | 88% | 3114 fps | 96.2% |
| Lovex S062 | <<locked>> | 82% | 52,794 psi | 87% | 2959 fps | 100% |
| Lovex S065 | <<locked>> | 88% | 52,504 psi | 86% | 2972 fps | 99.3% |
| Lovex S070 | <<locked>> | 90% | 53,853 psi | 88% | 3015 fps | 98.9% |
| Lovex S071ᴾ | <<locked>> | 100% | 46,267 psi | 76% | 2894 fps | 98.2% |
| Norma 203B | <<locked>> | 82% | 53,243 psi | 87% | 3009 fps | 100% |
| Norma 204 | <<locked>> | 90% | 52,402 psi | 86% | 3025 fps | 97% |
| Norma MRP | <<locked>> | 96% | 51,430 psi | 84% | 3104 fps | 98.4% |
| Norma URP | <<locked>> | 90% | 52,707 psi | 87% | 3038 fps | 99.9% |
| Ramshot Big Game | <<locked>> | 82% | 54,186 psi | 89% | 3038 fps | 100% |
| Ramshot Grandᴾ | <<locked>> | 100% | 54,346 psi | 89% | 3130 fps | 96.7% |
| Ramshot Hunter | <<locked>> | 92% | 55,042 psi | 90% | 3091 fps | 99.4% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 48,588 psi | 80% | 2995 fps | 97.3% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,101 psi | 61% | 1978 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 84% | 54,998 psi | 90% | 3018 fps | 99.2% |
| ReloadSwiss RS 60 | <<locked>> | 84% | 51,590 psi | 85% | 3074 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 90% | 53,780 psi | 88% | 3071 fps | 99.9% |
| ReloadSwiss RS 70 | <<locked>> | 90% | 52,359 psi | 86% | 3097 fps | 99.8% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 44,715 psi | 73% | 3005 fps | 97.2% |
| Rottweil R 902 | <<locked>> | 82% | 54,650 psi | 90% | 2972 fps | 100% |
| Rottweil R 903 | <<locked>> | 86% | 54,795 psi | 90% | 3018 fps | 100% |
| Rottweil R 904 | <<locked>> | 94% | 52,997 psi | 87% | 3005 fps | 96.1% |
| Rottweil R 905 | <<locked>> | 96% | 53,621 psi | 88% | 3068 fps | 97.6% |
| Rottweil R 907 | <<locked>> | 88% | 54,128 psi | 89% | 3002 fps | 98.3% |
| Shooters World Long Rifle | <<locked>> | 88% | 52,504 psi | 86% | 2972 fps | 99.3% |
| Shooters World Precision | <<locked>> | 82% | 52,794 psi | 87% | 2959 fps | 100% |
| Shooters World SW4350 | <<locked>> | 90% | 53,853 psi | 88% | 3015 fps | 98.9% |
| SNPE Vectan SP 11 | <<locked>> | 84% | 52,924 psi | 87% | 3022 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 84% | 52,243 psi | 86% | 2854 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 88% | 52,170 psi | 86% | 2923 fps | 98.5% |
| SNPE Vectan Tubal 8000 | <<locked>> | 96% | 53,156 psi | 87% | 3061 fps | 97.5% |
| Somchem S355 | <<locked>> | 86% | 54,723 psi | 90% | 3012 fps | 100% |
| Somchem S365 | <<locked>> | 92% | 52,069 psi | 85% | 3041 fps | 100% |
| Somchem S385 | <<locked>> | 96% | 54,302 psi | 89% | 3041 fps | 98.4% |
| Vihtavuori N135 | <<locked>> | 82% | 54,926 psi | 90% | 2933 fps | 100% |
| Vihtavuori N150 | <<locked>> | 86% | 52,576 psi | 86% | 2933 fps | 100% |
| Vihtavuori N160 | <<locked>> | 90% | 54,621 psi | 90% | 3031 fps | 99.9% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 53,679 psi | 88% | 3012 fps | 98% |
| Vihtavuori N540 | <<locked>> | 82% | 53,505 psi | 88% | 2940 fps | 100% |
| Vihtavuori N550 | <<locked>> | 90% | 53,780 psi | 88% | 3035 fps | 99.8% |
| Vihtavuori N555 | <<locked>> | 98% | 54,911 psi | 90% | 3100 fps | 100% |
| Winchester 6.5 StaBALL | <<locked>> | 90% | 54,375 psi | 89% | 2995 fps | 100% |
| Winchester 760 | <<locked>> | 88% | 52,576 psi | 86% | 3048 fps | 98.6% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 47,790 psi | 78% | 3133 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 98% | 54,389 psi | 89% | 3031 fps | 97.5% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2700 | <<locked>> | 80% | 50,198 psi | 82% | 2897 fps | 97.4% |
| Accurate 3100 | <<locked>> | 88% | 36,927 psi | 61% | 2700 fps | 95.7% |
| Accurate 4064 | <<locked>> | 80% | 49,806 psi | 82% | 2904 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 38,087 psi | 63% | 2749 fps | 97.7% |
| ADI AR 2208 | <<locked>> | 80% | 46,833 psi | 77% | 2871 fps | 99.6% |
| ADI AR 2209 | <<locked>> | 90% | 45,092 psi | 74% | 2910 fps | 95.2% |
| Alliant Power Pro Varmint | <<locked>> | 90% | 45,150 psi | 74% | 2907 fps | 95.3% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 47,398 psi | 78% | 2897 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 50,662 psi | 83% | 2969 fps | 99.9% |
| Alliant Reloder-16 | <<locked>> | 80% | 36,999 psi | 61% | 2759 fps | 97.7% |
| Alliant Reloder-17 | <<locked>> | 80% | 42,090 psi | 69% | 2894 fps | 99.8% |
| Alliant Reloder-19 | <<locked>> | 90% | 44,628 psi | 73% | 2897 fps | 95.2% |
| Alliant Reloder-22 | <<locked>> | 94% | 45,165 psi | 74% | 2949 fps | 95.5% |
| Alliant Reloder-23 | <<locked>> | 80% | 27,180 psi | 45% | 2490 fps | 95% |
| Alliant Reloder-25 | <<locked>> | 92% | 35,128 psi | 58% | 2736 fps | 95.5% |
| Alliant Reloder-26 | 88 gr | 84% | 33,547 psi | 55% | 2736 fps | 95.7% |
| Bofors RP15 | <<locked>> | 96% | 44,527 psi | 73% | 2933 fps | 95.2% |
| Bofors RP3 | <<locked>> | 80% | 47,805 psi | 78% | 2907 fps | 100% |
| Bofors RP5 | <<locked>> | 94% | 45,165 psi | 74% | 2949 fps | 95.5% |
| Bofors RP7 | <<locked>> | 80% | 42,090 psi | 69% | 2769 fps | 95.6% |
| Hodgdon H380 | <<locked>> | 80% | 48,196 psi | 79% | 2920 fps | 99.3% |
| Hodgdon H414 | <<locked>> | 80% | 40,001 psi | 66% | 2795 fps | 95.5% |
| Hodgdon H4350 | <<locked>> | 82% | 45,788 psi | 75% | 2881 fps | 95.8% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 34,461 psi | 57% | 2648 fps | 98.3% |
| Hodgdon Superformance | <<locked>> | 82% | 41,989 psi | 69% | 2871 fps | 95.8% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,209 psi | 45% | 1732 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 49,255 psi | 81% | 2910 fps | 99.9% |
| IMR 4166 Enduron | <<locked>> | 80% | 51,605 psi | 85% | 2936 fps | 98.3% |
| IMR 4350 | <<locked>> | 82% | 40,176 psi | 66% | 2746 fps | 95% |
| IMR 4451 Enduron | <<locked>> | 80% | 43,453 psi | 71% | 2802 fps | 96.5% |
| IMR 4831 | <<locked>> | 80% | 36,593 psi | 60% | 2700 fps | 97.3% |
| IMR 4955 Enduron | <<locked>> | 94% | 51,010 psi | 84% | 2959 fps | 95% |
| IMR 7828 SSC | <<locked>> | 98% | 50,285 psi | 83% | 3048 fps | 95.3% |
| Lovex S062 | <<locked>> | 80% | 49,559 psi | 81% | 2907 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 40,973 psi | 67% | 2749 fps | 97.2% |
| Lovex S070 | <<locked>> | 80% | 39,117 psi | 64% | 2723 fps | 95.5% |
| Lovex S071 | <<locked>> | 92% | 35,636 psi | 59% | 2667 fps | 95.1% |
| Norma 203B | <<locked>> | 80% | 50,009 psi | 82% | 2956 fps | 100% |
| Norma 204 | <<locked>> | 86% | 45,701 psi | 75% | 2897 fps | 95.2% |
| Norma MRP | 91.6 gr | 90% | 41,582 psi | 68% | 2904 fps | 95.9% |
| Norma URP | <<locked>> | 80% | 37,739 psi | 62% | 2743 fps | 97.5% |
| Ramshot Big Game | <<locked>> | 80% | 50,546 psi | 83% | 2976 fps | 100% |
| Ramshot Grand | <<locked>> | 98% | 50,546 psi | 83% | 3061 fps | 95.8% |
| Ramshot Hunter | <<locked>> | 80% | 36,637 psi | 60% | 2723 fps | 95.3% |
| Ramshot Magnum | <<locked>> | 96% | 41,930 psi | 69% | 2858 fps | 95.2% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,688 psi | 45% | 1772 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 48,138 psi | 79% | 2897 fps | 98.2% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 44,686 psi | 73% | 2953 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 37,826 psi | 62% | 2762 fps | 97.3% |
| ReloadSwiss RS 70 | 83.1 gr | 80% | 36,767 psi | 60% | 2769 fps | 96.6% |
| ReloadSwiss RS 76 | <<locked>> | 98% | 41,611 psi | 68% | 2933 fps | 96% |
| Rottweil R 902 | <<locked>> | 80% | 51,329 psi | 84% | 2920 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 44,976 psi | 74% | 2851 fps | 99.9% |
| Rottweil R 904 | <<locked>> | 92% | 49,719 psi | 82% | 2946 fps | 95.3% |
| Rottweil R 905 | <<locked>> | 90% | 43,830 psi | 72% | 2881 fps | 95.1% |
| Rottweil R 907 | <<locked>> | 80% | 42,090 psi | 69% | 2769 fps | 95.6% |
| Shooters World Long Rifle | <<locked>> | 80% | 40,973 psi | 67% | 2749 fps | 97.2% |
| Shooters World Precision | <<locked>> | 80% | 49,559 psi | 81% | 2907 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 39,117 psi | 64% | 2723 fps | 95.5% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 46,180 psi | 76% | 2904 fps | 99.8% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 46,224 psi | 76% | 2762 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 40,176 psi | 66% | 2690 fps | 95.7% |
| SNPE Vectan Tubal 8000 | <<locked>> | 90% | 43,439 psi | 71% | 2874 fps | 95% |
| Somchem S355 | <<locked>> | 80% | 45,281 psi | 74% | 2851 fps | 99.9% |
| Somchem S365 | <<locked>> | 80% | 34,330 psi | 56% | 2697 fps | 99.3% |
| Somchem S385 | <<locked>> | 88% | 41,611 psi | 68% | 2802 fps | 95.4% |
| Vihtavuori N135 | <<locked>> | 80% | 51,692 psi | 85% | 2887 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 43,192 psi | 71% | 2776 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 39,204 psi | 64% | 2743 fps | 97.9% |
| Vihtavuori N165 | <<locked>> | 94% | 43,816 psi | 72% | 2835 fps | 95.7% |
| Vihtavuori N540 | <<locked>> | 80% | 50,183 psi | 82% | 2887 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 38,754 psi | 64% | 2743 fps | 97.6% |
| Vihtavuori N555 | <<locked>> | 80% | 30,023 psi | 49% | 2575 fps | 95.3% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 38,377 psi | 63% | 2710 fps | 99.4% |
| Winchester 760 | <<locked>> | 80% | 40,132 psi | 66% | 2799 fps | 95.6% |
| Winchester StaBALL HD | <<locked>> | 84% | 27,499 psi | 45% | 2582 fps | 96% |
| Winchester Supreme 780 | <<locked>> | 94% | 47,195 psi | 77% | 2907 fps | 95.9% |
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 77 powders for .338 Lapua Mag. loaded with the .338 | 185gr | Hornady ECX. Alliant Reloder-26 delivers the highest muzzle velocity at 3,150 fps; across all powders the maximum-charge window runs from 1,936 fps to 3,150 fps. Alliant Reloder-23 gives the best case fill at 100 %, and 77 of the 77 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (420 MPa), the top charges use 60–90 %, leaving at least 10 % headroom. The 185.0 gr projectile in 0.338" calls for a 1:14.5 twist; slower twists will usually not stabilise this weight. Alliant Reloder-23, Alliant Reloder-25, Bofors RP15 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. Alliant Reloder-26, Norma MRP, ReloadSwiss RS 70 rank at the top here: for .338 Lapua Mag. with the .338 | 185gr | Hornady ECX 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.