Load Specifications
Load data in caliber .300 Norma Mag. with .308 | 155gr | Merlin Virtus bullet and 81 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 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: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2700 | <<locked>> | 82% | 57,246 psi | 90% | 3100 fps | 99.1% |
| Accurate 3100 | <<locked>> | 98% | 57,087 psi | 89% | 3153 fps | 99.9% |
| Accurate 4064 | <<locked>> | 82% | 56,710 psi | 89% | 3077 fps | 100% |
| Accurate 4350 | <<locked>> | 88% | 54,723 psi | 86% | 3140 fps | 100% |
| Accurate MAGPRO | <<locked>> | 96% | 55,999 psi | 88% | 3245 fps | 96.4% |
| ADI AR 2208 | <<locked>> | 84% | 56,768 psi | 89% | 3120 fps | 100% |
| ADI AR 2209 | <<locked>> | 94% | 56,043 psi | 88% | 3199 fps | 98.5% |
| ADI AR 2213 | <<locked>> | 98% | 57,711 psi | 90% | 3261 fps | 97.8% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 39,566 psi | 62% | 2930 fps | 96.4% |
| Alliant Reloder- TS 15.5 | <<locked>> | 82% | 54,259 psi | 85% | 3087 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 90% | 55,869 psi | 88% | 3209 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 86% | 57,217 psi | 90% | 3228 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 94% | 55,535 psi | 87% | 3182 fps | 98.4% |
| Alliant Reloder-22 | <<locked>> | 98% | 57,217 psi | 90% | 3251 fps | 98.8% |
| Alliant Reloder-23 | <<locked>> | 98% | 54,288 psi | 85% | 3169 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 50,053 psi | 78% | 3156 fps | 99.8% |
| Alliant Reloder-26 | <<locked>> | 94% | 54,665 psi | 86% | 3258 fps | 100% |
| Bofors RP15ᴾ | <<locked>> | 100% | 55,927 psi | 88% | 3228 fps | 98.5% |
| Bofors RP3 | <<locked>> | 82% | 55,056 psi | 86% | 3100 fps | 100% |
| Bofors RP5 | <<locked>> | 98% | 57,217 psi | 90% | 3251 fps | 98.8% |
| Bofors RP7 | <<locked>> | 86% | 54,389 psi | 85% | 3091 fps | 98.9% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 49,443 psi | 77% | 3094 fps | 96.9% |
| Hodgdon H380 | <<locked>> | 82% | 55,274 psi | 87% | 3120 fps | 100% |
| Hodgdon H414 | <<locked>> | 88% | 56,956 psi | 89% | 3202 fps | 99.5% |
| Hodgdon H4350 | <<locked>> | 86% | 56,304 psi | 88% | 3159 fps | 98.7% |
| Hodgdon H4831 | <<locked>> | 96% | 57,696 psi | 90% | 3196 fps | 97.1% |
| Hodgdon H4831 SC | <<locked>> | 96% | 56,391 psi | 88% | 3173 fps | 96.9% |
| Hodgdon Hybrid 100V | <<locked>> | 92% | 56,072 psi | 88% | 3123 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 48,994 psi | 77% | 3202 fps | 98.2% |
| Hodgdon Superformance | <<locked>> | 86% | 53,606 psi | 84% | 3173 fps | 99% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,666 psi | 57% | 2001 fps | 100% |
| IMR 4064 | <<locked>> | 82% | 56,028 psi | 88% | 3097 fps | 100% |
| IMR 4350 | <<locked>> | 90% | 55,869 psi | 88% | 3127 fps | 99.1% |
| IMR 4451 Enduron | <<locked>> | 86% | 56,043 psi | 88% | 3120 fps | 99.4% |
| IMR 4831 | <<locked>> | 90% | 55,288 psi | 87% | 3136 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 94% | 55,114 psi | 86% | 3117 fps | 96.8% |
| IMR 7828 SSC | <<locked>> | 98% | 55,143 psi | 86% | 3225 fps | 97.4% |
| Lovex S062 | <<locked>> | 82% | 56,362 psi | 88% | 3091 fps | 100% |
| Lovex S065 | <<locked>> | 88% | 56,289 psi | 88% | 3117 fps | 99.9% |
| Lovex S070 | <<locked>> | 88% | 54,404 psi | 85% | 3107 fps | 99.4% |
| Lovex S071ᴾ | <<locked>> | 100% | 50,676 psi | 79% | 3048 fps | 99.4% |
| Norma 203B | <<locked>> | 82% | 57,217 psi | 90% | 3150 fps | 100% |
| Norma 204 | <<locked>> | 90% | 56,927 psi | 89% | 3186 fps | 98.4% |
| Norma MRP | <<locked>> | 96% | 57,101 psi | 89% | 3278 fps | 99.6% |
| Norma URP | <<locked>> | 90% | 57,276 psi | 90% | 3189 fps | 100% |
| Ramshot Grand | <<locked>> | 98% | 55,869 psi | 88% | 3248 fps | 97.9% |
| Ramshot Hunter | <<locked>> | 90% | 56,130 psi | 88% | 3186 fps | 99.8% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 53,954 psi | 85% | 3173 fps | 98.9% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,391 psi | 59% | 2047 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 82% | 55,172 psi | 86% | 3104 fps | 99.6% |
| ReloadSwiss RS 60 | <<locked>> | 84% | 56,637 psi | 89% | 3215 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 88% | 55,071 psi | 86% | 3166 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 90% | 57,537 psi | 90% | 3264 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 49,516 psi | 78% | 3199 fps | 99.1% |
| Rottweil R 903 | <<locked>> | 84% | 55,303 psi | 87% | 3100 fps | 100% |
| Rottweil R 904 | <<locked>> | 94% | 57,508 psi | 90% | 3166 fps | 97.8% |
| Rottweil R 905 | <<locked>> | 94% | 54,737 psi | 86% | 3166 fps | 98.4% |
| Rottweil R 907 | <<locked>> | 86% | 54,389 psi | 85% | 3091 fps | 98.9% |
| Shooters World Long Rifle | <<locked>> | 88% | 56,289 psi | 88% | 3117 fps | 99.9% |
| Shooters World Precision | <<locked>> | 82% | 56,362 psi | 88% | 3091 fps | 100% |
| Shooters World SW4350 | <<locked>> | 88% | 54,404 psi | 85% | 3107 fps | 99.4% |
| SNPE Vectan SP 11 | <<locked>> | 84% | 57,145 psi | 90% | 3163 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 84% | 55,825 psi | 87% | 2979 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 88% | 55,825 psi | 87% | 3064 fps | 99.4% |
| SNPE Vectan Tubal 8000 | <<locked>> | 94% | 54,288 psi | 85% | 3163 fps | 98.3% |
| Somchem S355 | <<locked>> | 84% | 54,984 psi | 86% | 3091 fps | 100% |
| Somchem S361 | <<locked>> | 92% | 55,506 psi | 87% | 3094 fps | 96.7% |
| Somchem S365 | <<locked>> | 92% | 57,276 psi | 90% | 3189 fps | 100% |
| Somchem S385 | <<locked>> | 94% | 55,317 psi | 87% | 3140 fps | 99% |
| Vihtavuori N150 | <<locked>> | 86% | 56,579 psi | 89% | 3068 fps | 100% |
| Vihtavuori N160 | <<locked>> | 88% | 55,405 psi | 87% | 3123 fps | 100% |
| Vihtavuori N165 | <<locked>> | 98% | 54,911 psi | 86% | 3117 fps | 98.8% |
| Vihtavuori N540 | <<locked>> | 82% | 57,145 psi | 90% | 3064 fps | 100% |
| Vihtavuori N550 | <<locked>> | 88% | 54,694 psi | 86% | 3123 fps | 100% |
| Vihtavuori N555 | <<locked>> | 96% | 56,478 psi | 89% | 3196 fps | 100% |
| Vihtavuori N560 | <<locked>> | 96% | 57,043 psi | 89% | 3268 fps | 97.3% |
| Vihtavuori N565ᴾ | <<locked>> | 100% | 52,533 psi | 82% | 3163 fps | 96.6% |
| Winchester 6.5 StaBALL | <<locked>> | 88% | 55,274 psi | 87% | 3081 fps | 100% |
| Winchester 760 | <<locked>> | 88% | 57,159 psi | 90% | 3205 fps | 99.5% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 55,259 psi | 87% | 3307 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 96% | 55,608 psi | 87% | 3136 fps | 98.4% |
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% | 53,505 psi | 84% | 3038 fps | 98.6% |
| Accurate 3100 | <<locked>> | 84% | 34,882 psi | 55% | 2713 fps | 95.6% |
| Accurate 4064 | <<locked>> | 80% | 53,098 psi | 83% | 3025 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 41,321 psi | 65% | 2887 fps | 98.9% |
| Accurate MAGPRO | <<locked>> | 94% | 52,069 psi | 82% | 3176 fps | 95.5% |
| ADI AR 2208 | <<locked>> | 80% | 49,893 psi | 78% | 3002 fps | 100% |
| ADI AR 2209 | <<locked>> | 86% | 42,714 psi | 67% | 2933 fps | 95.3% |
| ADI AR 2213 | <<locked>> | 92% | 46,847 psi | 73% | 3051 fps | 95.1% |
| ADI AR 2225 | <<locked>> | 98% | 37,043 psi | 58% | 2861 fps | 95.2% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 50,821 psi | 80% | 3028 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 39,958 psi | 63% | 2900 fps | 99% |
| Alliant Reloder-17 | <<locked>> | 80% | 45,992 psi | 72% | 3038 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 86% | 42,496 psi | 67% | 2923 fps | 95.3% |
| Alliant Reloder-22 | <<locked>> | 90% | 43,265 psi | 68% | 2982 fps | 95.7% |
| Alliant Reloder-23 | <<locked>> | 80% | 29,283 psi | 46% | 2621 fps | 96.9% |
| Alliant Reloder-25 | <<locked>> | 88% | 33,446 psi | 52% | 2759 fps | 95.6% |
| Alliant Reloder-26 | 78 gr | 80% | 31,705 psi | 50% | 2743 fps | 95.5% |
| Bofors RP15 | <<locked>> | 92% | 42,815 psi | 67% | 2966 fps | 95.4% |
| Bofors RP3 | <<locked>> | 80% | 51,474 psi | 81% | 3041 fps | 100% |
| Bofors RP5 | <<locked>> | 90% | 43,265 psi | 68% | 2982 fps | 95.7% |
| Bofors RP7 | <<locked>> | 80% | 44,730 psi | 70% | 2904 fps | 97.1% |
| Hodgdon H1000 | <<locked>> | 98% | 46,122 psi | 72% | 3025 fps | 95.9% |
| Hodgdon H380 | <<locked>> | 80% | 51,764 psi | 81% | 3061 fps | 99.9% |
| Hodgdon H414 | <<locked>> | 80% | 43,381 psi | 68% | 2943 fps | 97.3% |
| Hodgdon H4350 | <<locked>> | 80% | 46,180 psi | 72% | 2969 fps | 96.7% |
| Hodgdon H4831 | <<locked>> | 92% | 50,154 psi | 79% | 3061 fps | 95.4% |
| Hodgdon H4831 SC | <<locked>> | 92% | 49,197 psi | 77% | 3041 fps | 95.1% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 37,434 psi | 59% | 2779 fps | 99.3% |
| Hodgdon Retumbo | <<locked>> | 96% | 42,844 psi | 67% | 3058 fps | 96.2% |
| Hodgdon Superformance | <<locked>> | 80% | 42,670 psi | 67% | 2956 fps | 96.8% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,383 psi | 43% | 1791 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 52,504 psi | 82% | 3041 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 40,437 psi | 63% | 2825 fps | 95.9% |
| IMR 4451 Enduron | <<locked>> | 80% | 46,311 psi | 73% | 2940 fps | 97.9% |
| IMR 4831 | <<locked>> | 80% | 39,523 psi | 62% | 2835 fps | 98.6% |
| IMR 4955 Enduron | <<locked>> | 90% | 48,486 psi | 76% | 2995 fps | 95.2% |
| IMR 7828 SSC | <<locked>> | 94% | 47,863 psi | 75% | 3084 fps | 95.5% |
| Lovex S062 | <<locked>> | 80% | 52,808 psi | 83% | 3035 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 43,685 psi | 68% | 2881 fps | 98.4% |
| Lovex S070 | <<locked>> | 80% | 41,945 psi | 66% | 2861 fps | 97.1% |
| Lovex S071 | <<locked>> | 88% | 33,968 psi | 53% | 2687 fps | 95.1% |
| Norma 203B | <<locked>> | 80% | 53,635 psi | 84% | 3091 fps | 100% |
| Norma 204 | <<locked>> | 82% | 43,062 psi | 67% | 2920 fps | 95.3% |
| Norma MRP | 81.4 gr | 86% | 39,566 psi | 62% | 2927 fps | 96% |
| Norma URP | <<locked>> | 80% | 40,930 psi | 64% | 2881 fps | 98.8% |
| Ramshot Grand | <<locked>> | 94% | 47,993 psi | 75% | 3100 fps | 96% |
| Ramshot Hunter | <<locked>> | 80% | 39,755 psi | 62% | 2864 fps | 97.1% |
| Ramshot Magnum | <<locked>> | 92% | 39,755 psi | 62% | 2887 fps | 95.4% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,804 psi | 44% | 1831 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 51,590 psi | 81% | 3041 fps | 99.2% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 48,878 psi | 77% | 3094 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 41,249 psi | 65% | 2904 fps | 98.7% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 39,856 psi | 62% | 2917 fps | 98.3% |
| ReloadSwiss RS 76 | <<locked>> | 94% | 39,668 psi | 62% | 2966 fps | 96.3% |
| Rottweil R 903 | <<locked>> | 80% | 48,370 psi | 76% | 2982 fps | 100% |
| Rottweil R 904 | <<locked>> | 88% | 47,195 psi | 74% | 2976 fps | 95.4% |
| Rottweil R 905 | <<locked>> | 86% | 41,626 psi | 65% | 2907 fps | 95.2% |
| Rottweil R 907 | <<locked>> | 80% | 44,730 psi | 70% | 2904 fps | 97.1% |
| Shooters World Long Rifle | <<locked>> | 80% | 43,685 psi | 68% | 2881 fps | 98.4% |
| Shooters World Precision | <<locked>> | 80% | 52,808 psi | 83% | 3035 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 41,945 psi | 66% | 2861 fps | 97.1% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 49,806 psi | 78% | 3045 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 49,081 psi | 77% | 2877 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 42,714 psi | 67% | 2822 fps | 97.2% |
| SNPE Vectan Tubal 8000 | <<locked>> | 86% | 41,263 psi | 65% | 2897 fps | 95% |
| Somchem S355 | <<locked>> | 80% | 48,428 psi | 76% | 2982 fps | 100% |
| Somchem S361 | <<locked>> | 90% | 51,938 psi | 81% | 3031 fps | 95.9% |
| Somchem S365 | <<locked>> | 80% | 37,579 psi | 59% | 2831 fps | 99.9% |
| Somchem S385 | <<locked>> | 84% | 39,392 psi | 62% | 2822 fps | 95.4% |
| Vihtavuori N150 | <<locked>> | 80% | 46,398 psi | 73% | 2904 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 42,380 psi | 66% | 2881 fps | 99% |
| Vihtavuori N165 | <<locked>> | 90% | 41,756 psi | 65% | 2864 fps | 95.8% |
| Vihtavuori N540 | <<locked>> | 80% | 53,635 psi | 84% | 3012 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 41,829 psi | 66% | 2881 fps | 98.8% |
| Vihtavuori N555 | <<locked>> | 80% | 32,721 psi | 51% | 2707 fps | 97% |
| Vihtavuori N560 | 87.1 gr | 92% | 49,458 psi | 78% | 3127 fps | 95.5% |
| Vihtavuori N565 | <<locked>> | 98% | 48,878 psi | 77% | 3094 fps | 95.7% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 41,553 psi | 65% | 2848 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 43,381 psi | 68% | 2943 fps | 97.3% |
| Winchester StaBALL HD | <<locked>> | 80% | 25,788 psi | 40% | 2582 fps | 95.6% |
| Winchester Supreme 780 | <<locked>> | 88% | 41,814 psi | 66% | 2871 fps | 95.1% |
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 81 powders for .300 Norma Mag. loaded with the .308 | 155gr | Merlin Virtus. Winchester StaBALL HD delivers the highest muzzle velocity at 3,307 fps; across all powders the maximum-charge window runs from 2,001 fps to 3,307 fps. ADI AR 2225 gives the best case fill at 100 %, and 81 of the 81 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (440 MPa), the top charges use 57–90 %, leaving at least 10 % headroom. The 155.0 gr projectile in 0.308" calls for a 1:12.5 twist; slower twists will usually not stabilise this weight. ADI AR 2225, 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, Vihtavuori N560 rank at the top here: for .300 Norma Mag. with the .308 | 155gr | Merlin Virtus 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.