Load Specifications
Load data in caliber .300 Win. Mag. with .308 | 185gr | Lapua Mega bullet and 86 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Alliant Reloder-26, Ramshot Grand and IMR 7828 SSC.
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: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2700 | <<locked>> | 84% | 53,911 psi | 86% | 2733 fps | 99% |
| Accurate 3100 | <<locked>> | 98% | 55,100 psi | 88% | 2828 fps | 99.9% |
| Accurate 4064 | <<locked>> | 82% | 55,999 psi | 90% | 2756 fps | 100% |
| Accurate 4350 | <<locked>> | 88% | 53,417 psi | 86% | 2818 fps | 100% |
| Accurate MAGPRO | <<locked>> | 98% | 54,230 psi | 87% | 2917 fps | 95.9% |
| ADI AR 2208 | <<locked>> | 84% | 55,593 psi | 89% | 2785 fps | 100% |
| ADI AR 2209 | <<locked>> | 94% | 54,114 psi | 87% | 2864 fps | 98.6% |
| ADI AR 2213 | <<locked>> | 98% | 55,376 psi | 89% | 2917 fps | 97.8% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 38,203 psi | 61% | 2635 fps | 96.7% |
| Alliant Power Pro Varmint | <<locked>> | 94% | 54,389 psi | 87% | 2861 fps | 98.6% |
| Alliant Reloder- TS 15.5 | <<locked>> | 82% | 53,127 psi | 85% | 2759 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 90% | 54,143 psi | 87% | 2874 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 86% | 55,259 psi | 89% | 2890 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 94% | 53,693 psi | 86% | 2851 fps | 98.6% |
| Alliant Reloder-22 | <<locked>> | 98% | 54,795 psi | 88% | 2913 fps | 98.9% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 55,622 psi | 89% | 2890 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 48,066 psi | 77% | 2831 fps | 99.9% |
| Alliant Reloder-26 | <<locked>> | 96% | 55,840 psi | 90% | 2979 fps | 100% |
| Bofors RP15ᴾ | <<locked>> | 100% | 53,722 psi | 86% | 2894 fps | 98.6% |
| Bofors RP3 | <<locked>> | 82% | 53,940 psi | 86% | 2776 fps | 100% |
| Bofors RP30ᴾ | <<locked>> | 100% | 43,947 psi | 70% | 2753 fps | 95.9% |
| Bofors RP5 | <<locked>> | 98% | 54,795 psi | 88% | 2913 fps | 98.9% |
| Bofors RP7 | <<locked>> | 86% | 53,156 psi | 85% | 2766 fps | 99.1% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 44,411 psi | 71% | 2710 fps | 96% |
| Hodgdon H380 | <<locked>> | 82% | 54,215 psi | 87% | 2795 fps | 100% |
| Hodgdon H414 | <<locked>> | 84% | 52,794 psi | 85% | 2831 fps | 99.4% |
| Hodgdon H4350 | <<locked>> | 88% | 53,345 psi | 86% | 2802 fps | 98.7% |
| Hodgdon H4831ᴾ | <<locked>> | 100% | 54,694 psi | 88% | 2844 fps | 97% |
| Hodgdon H4831 SC | <<locked>> | 96% | 54,433 psi | 87% | 2844 fps | 97% |
| Hodgdon Hybrid 100V | <<locked>> | 92% | 54,462 psi | 87% | 2799 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 82% | 55,912 psi | 90% | 2828 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 47,036 psi | 75% | 2874 fps | 98.3% |
| Hodgdon Superformance | <<locked>> | 88% | 55,622 psi | 89% | 2907 fps | 99.6% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,622 psi | 59% | 1752 fps | 100% |
| Hodgdon VARGET | <<locked>> | 82% | 55,056 psi | 88% | 2776 fps | 100% |
| IMR 4064 | <<locked>> | 84% | 54,505 psi | 87% | 2762 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 84% | 53,388 psi | 86% | 2746 fps | 99.4% |
| IMR 4350 | <<locked>> | 90% | 54,375 psi | 87% | 2802 fps | 99.3% |
| IMR 4451 Enduron | <<locked>> | 86% | 54,839 psi | 88% | 2792 fps | 99.5% |
| IMR 4831 | <<locked>> | 94% | 54,897 psi | 88% | 2825 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 94% | 53,490 psi | 86% | 2792 fps | 97% |
| IMR 7828 SSC | <<locked>> | 96% | 53,403 psi | 86% | 2897 fps | 97.6% |
| Lovex S062 | <<locked>> | 82% | 55,216 psi | 89% | 2762 fps | 100% |
| Lovex S065 | <<locked>> | 88% | 55,056 psi | 88% | 2789 fps | 99.9% |
| Lovex S070 | <<locked>> | 90% | 56,434 psi | 90% | 2835 fps | 99.8% |
| Lovex S071ᴾ | <<locked>> | 100% | 49,066 psi | 79% | 2736 fps | 99.5% |
| Norma 203B | <<locked>> | 82% | 55,956 psi | 90% | 2815 fps | 100% |
| Norma 204 | <<locked>> | 90% | 55,172 psi | 88% | 2854 fps | 98.6% |
| Norma MRP | <<locked>> | 96% | 54,636 psi | 88% | 2940 fps | 99.6% |
| Norma URP | <<locked>> | 90% | 55,477 psi | 89% | 2854 fps | 100% |
| Ramshot Grand | <<locked>> | 94% | 52,982 psi | 85% | 2900 fps | 97.8% |
| Ramshot Hunter | <<locked>> | 90% | 54,360 psi | 87% | 2858 fps | 99.9% |
| Ramshot Magnum | <<locked>> | 98% | 53,635 psi | 86% | 2881 fps | 99.2% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,376 psi | 60% | 1795 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 82% | 53,940 psi | 86% | 2779 fps | 99.7% |
| ReloadSwiss RS 60 | <<locked>> | 84% | 54,665 psi | 88% | 2881 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 88% | 53,127 psi | 85% | 2838 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 90% | 55,201 psi | 89% | 2920 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 47,268 psi | 76% | 2874 fps | 99.2% |
| Rottweil R 903 | <<locked>> | 84% | 54,302 psi | 87% | 2776 fps | 100% |
| Rottweil R 904 | <<locked>> | 94% | 55,767 psi | 89% | 2835 fps | 97.9% |
| Rottweil R 905 | <<locked>> | 94% | 53,069 psi | 85% | 2841 fps | 98.6% |
| Rottweil R 907 | <<locked>> | 86% | 53,156 psi | 85% | 2766 fps | 99.1% |
| Shooters World Long Rifle | <<locked>> | 88% | 55,056 psi | 88% | 2789 fps | 99.9% |
| Shooters World Precision | <<locked>> | 82% | 55,216 psi | 89% | 2762 fps | 100% |
| Shooters World SW4350 | <<locked>> | 90% | 56,434 psi | 90% | 2835 fps | 99.8% |
| SNPE Vectan SP 11 | <<locked>> | 84% | 55,608 psi | 89% | 2831 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 84% | 54,752 psi | 88% | 2657 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 88% | 54,520 psi | 87% | 2743 fps | 99.5% |
| SNPE Vectan Tubal 8000 | <<locked>> | 96% | 56,231 psi | 90% | 2894 fps | 99% |
| Somchem S355 | <<locked>> | 84% | 54,114 psi | 87% | 2769 fps | 100% |
| Somchem S361 | <<locked>> | 92% | 53,751 psi | 86% | 2772 fps | 96.8% |
| Somchem S365 | <<locked>> | 92% | 55,317 psi | 89% | 2858 fps | 100% |
| Somchem S385 | <<locked>> | 94% | 53,664 psi | 86% | 2818 fps | 99.2% |
| Unknown powder | <<locked>> | 88% | 56,086 psi | 90% | 2861 fps | 100% |
| Vihtavuori N150 | <<locked>> | 90% | 55,651 psi | 89% | 2753 fps | 100% |
| Vihtavuori N160 | <<locked>> | 88% | 56,347 psi | 90% | 2825 fps | 100% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 54,534 psi | 87% | 2815 fps | 99% |
| Vihtavuori N550 | <<locked>> | 86% | 53,388 psi | 86% | 2822 fps | 100% |
| Vihtavuori N555 | <<locked>> | 96% | 54,578 psi | 88% | 2867 fps | 100% |
| Vihtavuori N560 | <<locked>> | 98% | 55,027 psi | 88% | 2936 fps | 97.5% |
| Vihtavuori N565ᴾ | <<locked>> | 100% | 50,270 psi | 81% | 2841 fps | 96.7% |
| Winchester 6.5 StaBALL | <<locked>> | 88% | 53,359 psi | 86% | 2759 fps | 100% |
| Winchester 760 | <<locked>> | 84% | 52,794 psi | 85% | 2831 fps | 99.4% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 51,735 psi | 83% | 2966 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 94% | 55,288 psi | 89% | 2835 fps | 98.7% |
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% | 47,239 psi | 76% | 2621 fps | 98% |
| Accurate 3100 | <<locked>> | 82% | 32,068 psi | 51% | 2392 fps | 95.4% |
| Accurate 4064 | <<locked>> | 80% | 52,533 psi | 84% | 2707 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 40,596 psi | 65% | 2595 fps | 99.3% |
| Accurate MAGPRO | <<locked>> | 96% | 50,560 psi | 81% | 2854 fps | 95% |
| ADI AR 2208 | <<locked>> | 80% | 49,023 psi | 79% | 2684 fps | 100% |
| ADI AR 2209 | <<locked>> | 86% | 41,684 psi | 67% | 2635 fps | 95.8% |
| ADI AR 2213 | <<locked>> | 92% | 45,281 psi | 73% | 2736 fps | 95.4% |
| ADI AR 2225 | <<locked>> | 98% | 35,868 psi | 58% | 2575 fps | 95.6% |
| Alliant Power Pro Varmint | <<locked>> | 84% | 39,175 psi | 63% | 2575 fps | 95% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 49,864 psi | 80% | 2710 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 39,131 psi | 63% | 2602 fps | 99.3% |
| Alliant Reloder-17 | <<locked>> | 80% | 44,788 psi | 72% | 2726 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 86% | 41,582 psi | 67% | 2628 fps | 95.9% |
| Alliant Reloder-22 | <<locked>> | 88% | 39,291 psi | 63% | 2621 fps | 95.2% |
| Alliant Reloder-23 | <<locked>> | 80% | 28,935 psi | 46% | 2365 fps | 97.8% |
| Alliant Reloder-25 | <<locked>> | 86% | 30,763 psi | 49% | 2431 fps | 95.2% |
| Alliant Reloder-26 | 65 gr | 80% | 31,125 psi | 50% | 2484 fps | 96.4% |
| Bofors RP15 | <<locked>> | 92% | 41,350 psi | 66% | 2667 fps | 95.8% |
| Bofors RP3 | <<locked>> | 80% | 50,575 psi | 81% | 2726 fps | 100% |
| Bofors RP30 | <<locked>> | 98% | 41,118 psi | 66% | 2694 fps | 95% |
| Bofors RP5 | <<locked>> | 88% | 39,291 psi | 63% | 2621 fps | 95.2% |
| Bofors RP7 | <<locked>> | 80% | 44,150 psi | 71% | 2605 fps | 97.6% |
| Hodgdon H1000 | <<locked>> | 98% | 41,582 psi | 67% | 2651 fps | 95% |
| Hodgdon H380 | <<locked>> | 80% | 50,647 psi | 81% | 2736 fps | 99.9% |
| Hodgdon H414 | <<locked>> | 80% | 46,035 psi | 74% | 2710 fps | 98.5% |
| Hodgdon H4350 | <<locked>> | 80% | 41,582 psi | 67% | 2585 fps | 96.2% |
| Hodgdon H4831 | <<locked>> | 96% | 48,109 psi | 77% | 2736 fps | 95.5% |
| Hodgdon H4831 SC | <<locked>> | 92% | 47,500 psi | 76% | 2723 fps | 95.4% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 36,738 psi | 59% | 2493 fps | 99.6% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 52,272 psi | 84% | 2776 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 94% | 38,783 psi | 62% | 2684 fps | 95.5% |
| Hodgdon Superformance | <<locked>> | 80% | 41,408 psi | 66% | 2657 fps | 97.2% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,543 psi | 44% | 1568 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 51,706 psi | 83% | 2723 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 48,356 psi | 78% | 2664 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 80% | 47,326 psi | 76% | 2641 fps | 98.6% |
| IMR 4350 | <<locked>> | 80% | 39,740 psi | 64% | 2533 fps | 96.4% |
| IMR 4451 Enduron | <<locked>> | 80% | 45,542 psi | 73% | 2635 fps | 98.2% |
| IMR 4831 | <<locked>> | 80% | 35,404 psi | 57% | 2470 fps | 98.3% |
| IMR 4955 Enduron | <<locked>> | 90% | 47,239 psi | 76% | 2684 fps | 95.5% |
| IMR 7828 SSC | 71.4 gr | 92% | 46,543 psi | 75% | 2772 fps | 95.9% |
| Lovex S062 | <<locked>> | 80% | 52,069 psi | 83% | 2713 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 43,105 psi | 69% | 2585 fps | 98.8% |
| Lovex S070 | <<locked>> | 80% | 41,423 psi | 66% | 2569 fps | 97.6% |
| Lovex S071 | <<locked>> | 86% | 31,357 psi | 50% | 2372 fps | 95.1% |
| Norma 203B | <<locked>> | 80% | 52,576 psi | 84% | 2766 fps | 100% |
| Norma 204 | <<locked>> | 82% | 41,989 psi | 67% | 2618 fps | 95.7% |
| Norma MRP | <<locked>> | 84% | 35,868 psi | 58% | 2572 fps | 95.5% |
| Norma URP | <<locked>> | 80% | 40,219 psi | 64% | 2589 fps | 99.2% |
| Ramshot Grand | 73.1 gr | 90% | 45,542 psi | 73% | 2766 fps | 96% |
| Ramshot Hunter | <<locked>> | 80% | 38,986 psi | 63% | 2575 fps | 97.6% |
| Ramshot Magnum | <<locked>> | 88% | 36,811 psi | 59% | 2559 fps | 95.1% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,108 psi | 45% | 1608 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 50,459 psi | 81% | 2720 fps | 99.4% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 47,543 psi | 76% | 2772 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 40,364 psi | 65% | 2615 fps | 99.1% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 38,986 psi | 63% | 2625 fps | 98.7% |
| ReloadSwiss RS 76 | <<locked>> | 92% | 35,694 psi | 57% | 2602 fps | 95.3% |
| Rottweil R 903 | <<locked>> | 80% | 47,703 psi | 76% | 2674 fps | 100% |
| Rottweil R 904 | <<locked>> | 86% | 43,149 psi | 69% | 2612 fps | 95% |
| Rottweil R 905 | <<locked>> | 86% | 40,727 psi | 65% | 2612 fps | 95.8% |
| Rottweil R 907 | <<locked>> | 80% | 44,150 psi | 71% | 2605 fps | 97.6% |
| Shooters World Long Rifle | <<locked>> | 80% | 43,105 psi | 69% | 2585 fps | 98.8% |
| Shooters World Precision | <<locked>> | 80% | 52,069 psi | 83% | 2713 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 41,423 psi | 66% | 2569 fps | 97.6% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 48,805 psi | 78% | 2726 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 48,327 psi | 77% | 2566 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 42,235 psi | 68% | 2533 fps | 97.7% |
| SNPE Vectan Tubal 8000 | <<locked>> | 86% | 40,350 psi | 65% | 2608 fps | 95.7% |
| Somchem S355 | <<locked>> | 80% | 47,688 psi | 76% | 2671 fps | 100% |
| Somchem S361 | <<locked>> | 88% | 47,137 psi | 76% | 2661 fps | 95.2% |
| Somchem S365 | <<locked>> | 80% | 36,782 psi | 59% | 2546 fps | 100% |
| Somchem S385 | <<locked>> | 82% | 36,187 psi | 58% | 2484 fps | 95.2% |
| Unknown powder | <<locked>> | 80% | 43,105 psi | 69% | 2641 fps | 99.2% |
| Vihtavuori N150 | <<locked>> | 80% | 40,988 psi | 66% | 2520 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 43,337 psi | 69% | 2615 fps | 99.5% |
| Vihtavuori N165 | <<locked>> | 88% | 36,840 psi | 59% | 2493 fps | 95% |
| Vihtavuori N550 | <<locked>> | 80% | 43,801 psi | 70% | 2657 fps | 99.5% |
| Vihtavuori N555 | <<locked>> | 80% | 32,184 psi | 52% | 2441 fps | 97.8% |
| Vihtavuori N560 | <<locked>> | 92% | 45,049 psi | 72% | 2759 fps | 95% |
| Vihtavuori N565 | <<locked>> | 98% | 46,876 psi | 75% | 2779 fps | 95.8% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 40,495 psi | 65% | 2552 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 46,035 psi | 74% | 2710 fps | 98.5% |
| Winchester StaBALL HD | <<locked>> | 80% | 25,628 psi | 41% | 2349 fps | 97% |
| Winchester Supreme 780 | <<locked>> | 86% | 41,524 psi | 67% | 2598 fps | 95.8% |
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 86 powders for .300 Win. Mag. loaded with the .308 | 185gr | Lapua Mega. Alliant Reloder-26 delivers the highest muzzle velocity at 2,979 fps; across all powders the maximum-charge window runs from 1,752 fps to 2,979 fps. ADI AR 2225 gives the best case fill at 100 %, and 86 of the 86 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (430 MPa), the top charges use 59–90 %, 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 2225, Alliant Reloder-23, Alliant Reloder-25 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, Ramshot Grand, IMR 7828 SSC rank at the top here: for .300 Win. Mag. with the .308 | 185gr | Lapua Mega 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.