Load Specifications
Load data in caliber .300 Lapua Mag. with .308 | 185gr | Lapua Mega bullet and 68 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 Alliant Reloder-26.
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: 26"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 3100 | <<locked>> | 92% | 54,201 psi | 89% | 2913 fps | 100% |
| Accurate 4350 | <<locked>> | 82% | 51,764 psi | 85% | 2887 fps | 100% |
| Accurate MAGPRO | <<locked>> | 92% | 53,490 psi | 88% | 3015 fps | 97.6% |
| ADI AR 2209 | <<locked>> | 88% | 52,591 psi | 86% | 2949 fps | 99.5% |
| ADI AR 2213 | <<locked>> | 92% | 53,940 psi | 89% | 3012 fps | 99% |
| ADI AR 2217ᴾ | <<locked>> | 100% | 51,866 psi | 85% | 2969 fps | 99% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 46,514 psi | 76% | 2933 fps | 99.9% |
| Alliant Reloder-16 | <<locked>> | 84% | 52,678 psi | 86% | 2943 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 88% | 52,214 psi | 86% | 2936 fps | 99.4% |
| Alliant Reloder-22 | <<locked>> | 92% | 54,114 psi | 89% | 3009 fps | 99.7% |
| Alliant Reloder-23 | <<locked>> | 92% | 52,083 psi | 86% | 2927 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 98% | 54,824 psi | 90% | 3038 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 88% | 51,924 psi | 85% | 3009 fps | 100% |
| Baschieri & Pellagri 109 | <<locked>> | 92% | 52,083 psi | 86% | 2910 fps | 96.2% |
| Bofors RP15 | <<locked>> | 94% | 53,330 psi | 88% | 2995 fps | 99.6% |
| Bofors RP30ᴾ | <<locked>> | 100% | 54,650 psi | 90% | 3045 fps | 99.5% |
| Bofors RP5 | <<locked>> | 92% | 54,114 psi | 89% | 3009 fps | 99.7% |
| Bofors RP7 | <<locked>> | 82% | 53,925 psi | 89% | 2890 fps | 99.9% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 53,287 psi | 87% | 2995 fps | 99.5% |
| Hodgdon H4350 | <<locked>> | 84% | 54,360 psi | 89% | 2930 fps | 99.7% |
| Hodgdon H4831 | <<locked>> | 94% | 53,301 psi | 88% | 2940 fps | 98.4% |
| Hodgdon H4831 SC | <<locked>> | 90% | 52,692 psi | 87% | 2930 fps | 98.3% |
| Hodgdon Hybrid 100V | <<locked>> | 86% | 52,953 psi | 87% | 2867 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 98% | 53,809 psi | 88% | 3120 fps | 100% |
| Hodgdon Superformance | <<locked>> | 82% | 53,563 psi | 88% | 2976 fps | 99.9% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,173 psi | 61% | 1857 fps | 100% |
| IMR 4350 | <<locked>> | 84% | 52,272 psi | 86% | 2877 fps | 99.8% |
| IMR 4831 | <<locked>> | 88% | 53,621 psi | 88% | 2904 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 90% | 54,723 psi | 90% | 2930 fps | 98.7% |
| IMR 7828 SSC | <<locked>> | 90% | 52,040 psi | 85% | 2989 fps | 98.8% |
| IMR 8133 Enduronᴾ | <<locked>> | 100% | 42,047 psi | 69% | 2835 fps | 97.1% |
| Lovex S065 | <<locked>> | 82% | 52,620 psi | 86% | 2858 fps | 100% |
| Lovex S070 | <<locked>> | 84% | 54,346 psi | 89% | 2907 fps | 100% |
| Lovex S071 | <<locked>> | 96% | 51,982 psi | 85% | 2881 fps | 100% |
| Norma 204 | <<locked>> | 84% | 52,953 psi | 87% | 2930 fps | 99.4% |
| Norma 217ᴾ | <<locked>> | 100% | 42,148 psi | 69% | 2861 fps | 99% |
| Norma MRP | <<locked>> | 90% | 53,954 psi | 89% | 3028 fps | 100% |
| Norma URP | <<locked>> | 84% | 53,882 psi | 88% | 2927 fps | 100% |
| Ramshot Grand | <<locked>> | 88% | 51,619 psi | 85% | 2992 fps | 99.1% |
| Ramshot Hunter | <<locked>> | 84% | 52,678 psi | 86% | 2933 fps | 100% |
| Ramshot Magnum | <<locked>> | 92% | 52,808 psi | 87% | 2969 fps | 99.9% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 38,072 psi | 63% | 1903 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 82% | 51,822 psi | 85% | 2913 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 84% | 53,664 psi | 88% | 2992 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 98% | 54,447 psi | 89% | 3114 fps | 100% |
| ReloadSwiss RS 80ᴾ | <<locked>> | 100% | 53,548 psi | 88% | 3068 fps | 98.5% |
| Rottweil R 904 | <<locked>> | 88% | 53,679 psi | 88% | 2917 fps | 98.9% |
| Rottweil R 905 | <<locked>> | 88% | 51,692 psi | 85% | 2923 fps | 99.5% |
| Rottweil R 907 | <<locked>> | 82% | 53,925 psi | 89% | 2890 fps | 99.9% |
| Shooters World Long Rifle | <<locked>> | 82% | 52,620 psi | 86% | 2858 fps | 100% |
| Shooters World SW4350 | <<locked>> | 84% | 54,346 psi | 89% | 2907 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 84% | 55,085 psi | 90% | 2861 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 90% | 54,882 psi | 90% | 2979 fps | 99.7% |
| Somchem S361 | <<locked>> | 86% | 51,561 psi | 85% | 2851 fps | 98.1% |
| Somchem S365 | <<locked>> | 86% | 54,375 psi | 89% | 2930 fps | 100% |
| Somchem S385 | <<locked>> | 88% | 52,156 psi | 86% | 2897 fps | 99.8% |
| Unknown powder | <<locked>> | 82% | 53,867 psi | 88% | 2927 fps | 100% |
| Vihtavuori N150 | <<locked>> | 84% | 53,534 psi | 88% | 2815 fps | 100% |
| Vihtavuori N160 | <<locked>> | 82% | 54,128 psi | 89% | 2894 fps | 100% |
| Vihtavuori N165 | <<locked>> | 94% | 53,534 psi | 88% | 2907 fps | 99.8% |
| Vihtavuori N550 | <<locked>> | 82% | 54,752 psi | 90% | 2940 fps | 100% |
| Vihtavuori N555 | <<locked>> | 90% | 54,143 psi | 89% | 2953 fps | 100% |
| Vihtavuori N560 | <<locked>> | 92% | 54,462 psi | 89% | 3038 fps | 98.8% |
| Vihtavuori N565 | <<locked>> | 96% | 53,925 psi | 89% | 3009 fps | 98.9% |
| Vihtavuori N568ᴾ | <<locked>> | 100% | 54,433 psi | 89% | 3068 fps | 98.1% |
| Winchester 6.5 StaBALL | <<locked>> | 84% | 54,839 psi | 90% | 2871 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 94% | 53,650 psi | 88% | 3061 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 88% | 53,127 psi | 87% | 2910 fps | 99.5% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 26"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 3100 | <<locked>> | 80% | 36,187 psi | 59% | 2579 fps | 98.4% |
| Accurate 4350 | <<locked>> | 80% | 48,298 psi | 79% | 2831 fps | 100% |
| Accurate MAGPRO | <<locked>> | 86% | 43,381 psi | 71% | 2822 fps | 95% |
| ADI AR 2209 | <<locked>> | 80% | 40,118 psi | 66% | 2707 fps | 97.2% |
| ADI AR 2213 | <<locked>> | 82% | 38,435 psi | 63% | 2697 fps | 95.2% |
| ADI AR 2217 | <<locked>> | 90% | 37,173 psi | 61% | 2664 fps | 95.1% |
| ADI AR 2225 | <<locked>> | 88% | 31,401 psi | 52% | 2562 fps | 95.9% |
| Alliant Reloder-16 | <<locked>> | 80% | 46,253 psi | 76% | 2838 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 40,205 psi | 66% | 2703 fps | 97.2% |
| Alliant Reloder-22 | <<locked>> | 80% | 36,114 psi | 59% | 2648 fps | 96.1% |
| Alliant Reloder-23 | <<locked>> | 80% | 34,824 psi | 57% | 2608 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 30,153 psi | 50% | 2516 fps | 97.2% |
| Alliant Reloder-26 | 75.9 gr | 80% | 38,334 psi | 63% | 2753 fps | 99.8% |
| Baschieri & Pellagri 109 | <<locked>> | 90% | 49,052 psi | 81% | 2854 fps | 95.4% |
| Bofors RP15 | <<locked>> | 82% | 35,940 psi | 59% | 2641 fps | 95.8% |
| Bofors RP30 | <<locked>> | 88% | 36,289 psi | 60% | 2680 fps | 95.3% |
| Bofors RP5 | <<locked>> | 80% | 36,114 psi | 59% | 2648 fps | 96.1% |
| Bofors RP7 | <<locked>> | 80% | 50,517 psi | 83% | 2831 fps | 99.7% |
| Hodgdon H1000 | <<locked>> | 88% | 35,650 psi | 59% | 2628 fps | 95.1% |
| Hodgdon H4350 | <<locked>> | 80% | 48,051 psi | 79% | 2822 fps | 99% |
| Hodgdon H4831 | <<locked>> | 86% | 41,234 psi | 68% | 2710 fps | 95.6% |
| Hodgdon H4831 SC | <<locked>> | 82% | 40,292 psi | 66% | 2690 fps | 95.3% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 43,569 psi | 72% | 2713 fps | 100% |
| Hodgdon Retumbo | 74.6 gr | 84% | 33,721 psi | 55% | 2664 fps | 95.6% |
| Hodgdon Superformance | <<locked>> | 80% | 49,690 psi | 82% | 2910 fps | 99.7% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,920 psi | 46% | 1663 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 45,890 psi | 75% | 2762 fps | 99.2% |
| IMR 4831 | <<locked>> | 80% | 41,626 psi | 68% | 2694 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 39,885 psi | 65% | 2644 fps | 95.3% |
| IMR 7828 SSC | <<locked>> | 82% | 39,465 psi | 65% | 2736 fps | 95.8% |
| IMR 8133 Enduron | <<locked>> | 96% | 36,753 psi | 60% | 2710 fps | 95.2% |
| Lovex S065 | <<locked>> | 80% | 49,487 psi | 81% | 2805 fps | 100% |
| Lovex S070 | <<locked>> | 80% | 47,921 psi | 79% | 2799 fps | 99.7% |
| Lovex S071 | <<locked>> | 80% | 31,256 psi | 51% | 2457 fps | 96.9% |
| Norma 204 | <<locked>> | 80% | 46,108 psi | 76% | 2805 fps | 98.4% |
| Norma 217 | <<locked>> | 92% | 32,256 psi | 53% | 2615 fps | 95.8% |
| Norma MRP | <<locked>> | 80% | 37,855 psi | 62% | 2717 fps | 98% |
| Norma URP | <<locked>> | 80% | 47,282 psi | 78% | 2818 fps | 100% |
| Ramshot Grand | <<locked>> | 80% | 38,189 psi | 63% | 2720 fps | 95.8% |
| Ramshot Hunter | <<locked>> | 80% | 46,006 psi | 76% | 2815 fps | 99.8% |
| Ramshot Magnum | <<locked>> | 80% | 33,315 psi | 55% | 2572 fps | 95.9% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,645 psi | 47% | 1703 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 48,283 psi | 79% | 2851 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 46,398 psi | 76% | 2874 fps | 100% |
| ReloadSwiss RS 76 | 77.9 gr | 82% | 30,560 psi | 50% | 2569 fps | 95.3% |
| ReloadSwiss RS 80 | <<locked>> | 94% | 42,496 psi | 70% | 2854 fps | 95.8% |
| Rottweil R 904 | <<locked>> | 80% | 41,452 psi | 68% | 2687 fps | 96.4% |
| Rottweil R 905 | <<locked>> | 80% | 39,639 psi | 65% | 2690 fps | 97.3% |
| Rottweil R 907 | <<locked>> | 80% | 50,517 psi | 83% | 2831 fps | 99.7% |
| Shooters World Long Rifle | <<locked>> | 80% | 49,487 psi | 81% | 2805 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 47,921 psi | 79% | 2799 fps | 99.7% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 48,472 psi | 80% | 2753 fps | 99.7% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 39,305 psi | 65% | 2684 fps | 97.1% |
| Somchem S361 | <<locked>> | 80% | 42,163 psi | 69% | 2674 fps | 95.9% |
| Somchem S365 | <<locked>> | 80% | 44,309 psi | 73% | 2769 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 40,190 psi | 66% | 2674 fps | 98.1% |
| Unknown powder | <<locked>> | 80% | 50,386 psi | 83% | 2871 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 47,210 psi | 78% | 2720 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 50,647 psi | 83% | 2838 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 33,895 psi | 56% | 2520 fps | 95.8% |
| Vihtavuori N550 | <<locked>> | 80% | 51,329 psi | 84% | 2887 fps | 100% |
| Vihtavuori N555 | <<locked>> | 80% | 38,972 psi | 64% | 2680 fps | 99.9% |
| Vihtavuori N560 | <<locked>> | 84% | 41,495 psi | 68% | 2789 fps | 95.9% |
| Vihtavuori N565 | <<locked>> | 86% | 38,334 psi | 63% | 2700 fps | 95.1% |
| Vihtavuori N568 | <<locked>> | 94% | 43,845 psi | 72% | 2871 fps | 95.6% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 47,761 psi | 78% | 2766 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 80% | 30,951 psi | 51% | 2635 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 40,059 psi | 66% | 2671 fps | 97.2% |
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 73 powders for .300 Lapua Mag. loaded with the .308 | 185gr | Lapua Mega. Hodgdon Retumbo delivers the highest muzzle velocity at 3,120 fps; across all powders the maximum-charge window runs from 1,857 fps to 3,120 fps. ADI AR 2217 gives the best case fill at 100 %, and 73 of the 73 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (420 MPa), the top charges use 61–90 %, leaving at least 10 % headroom. The 185.0 gr projectile in 0.308" calls for a 1:15.5 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. Hodgdon Retumbo, ReloadSwiss RS 76, Alliant Reloder-26 rank at the top here: for .300 Lapua Mag. with the .308 | 185gr | Lapua Mega they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, ADI AR 2218, IMR 7977 Enduron, Vihtavuori N170 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.