Load Specifications
Load data in caliber .300 Blaser Mag. with .308 | 171gr | Viper Bullets Bush Gold bullet and 84 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Alliant Reloder-26, Accurate High Country and Norma MRP.
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: 25.6"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2700 | <<locked>> | 82% | 55,013 psi | 90% | 2920 fps | 99.1% |
| Accurate 3100 | <<locked>> | 98% | 53,751 psi | 88% | 2972 fps | 99.8% |
| Accurate 4064 | <<locked>> | 82% | 54,781 psi | 90% | 2907 fps | 100% |
| Accurate 4350 | <<locked>> | 88% | 51,996 psi | 85% | 2966 fps | 100% |
| Accurate High Country | <<locked>> | 96% | 55,114 psi | 90% | 3127 fps | 98% |
| Accurate MAGPRO | <<locked>> | 96% | 52,054 psi | 85% | 3054 fps | 96.1% |
| ADI AR 2208 | <<locked>> | 84% | 54,418 psi | 89% | 2940 fps | 100% |
| ADI AR 2209 | <<locked>> | 94% | 53,040 psi | 87% | 3015 fps | 98.3% |
| ADI AR 2213 | <<locked>> | 98% | 54,302 psi | 89% | 3068 fps | 97.5% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 37,463 psi | 62% | 2772 fps | 96.3% |
| Alliant Power Pro Varmint | <<locked>> | 94% | 53,185 psi | 87% | 3009 fps | 98.4% |
| Alliant Power Pro Varmint | <<locked>> | 94% | 53,185 psi | 87% | 3009 fps | 98.4% |
| Alliant Reloder- TS 15.5 | <<locked>> | 82% | 51,996 psi | 85% | 2910 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 90% | 52,953 psi | 87% | 3028 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 86% | 54,041 psi | 89% | 3048 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 94% | 52,547 psi | 86% | 3002 fps | 98.3% |
| Alliant Reloder-22 | <<locked>> | 98% | 53,563 psi | 88% | 3064 fps | 98.6% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 54,186 psi | 89% | 3045 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 46,963 psi | 77% | 2979 fps | 99.8% |
| Alliant Reloder-26 | <<locked>> | 96% | 54,520 psi | 90% | 3136 fps | 100% |
| Bofors RP15ᴾ | <<locked>> | 100% | 52,533 psi | 86% | 3045 fps | 98.4% |
| Bofors RP3 | <<locked>> | 82% | 52,779 psi | 87% | 2927 fps | 100% |
| Bofors RP5 | <<locked>> | 98% | 53,563 psi | 88% | 3064 fps | 98.6% |
| Bofors RP7 | <<locked>> | 86% | 52,228 psi | 86% | 2913 fps | 98.9% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 46,557 psi | 76% | 2913 fps | 96.5% |
| Hodgdon H380 | <<locked>> | 82% | 53,055 psi | 87% | 2946 fps | 100% |
| Hodgdon H414 | <<locked>> | 88% | 54,215 psi | 89% | 3022 fps | 99.5% |
| Hodgdon H4350 | <<locked>> | 86% | 53,722 psi | 88% | 2976 fps | 98.7% |
| Hodgdon H4831 | <<locked>> | 96% | 54,418 psi | 89% | 3009 fps | 96.9% |
| Hodgdon H4831 SC | <<locked>> | 96% | 53,258 psi | 87% | 2989 fps | 96.7% |
| Hodgdon Hybrid 100V | <<locked>> | 92% | 53,156 psi | 87% | 2946 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 46,079 psi | 76% | 3022 fps | 98% |
| Hodgdon Superformance | <<locked>> | 88% | 54,259 psi | 89% | 3058 fps | 99.4% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,550 psi | 60% | 1867 fps | 100% |
| IMR 4064 | <<locked>> | 82% | 53,969 psi | 89% | 2920 fps | 100% |
| IMR 4350 | <<locked>> | 90% | 53,243 psi | 87% | 2949 fps | 99.1% |
| IMR 4451 Enduron | <<locked>> | 86% | 53,693 psi | 88% | 2943 fps | 99.3% |
| IMR 4831 | <<locked>> | 90% | 52,692 psi | 87% | 2963 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 94% | 52,504 psi | 86% | 2940 fps | 96.7% |
| IMR 7828 SSC | <<locked>> | 98% | 51,866 psi | 85% | 3038 fps | 97.1% |
| Lovex S062 | <<locked>> | 82% | 54,172 psi | 89% | 2913 fps | 100% |
| Lovex S065 | <<locked>> | 88% | 53,954 psi | 89% | 2940 fps | 99.9% |
| Lovex S070 | <<locked>> | 88% | 52,098 psi | 86% | 2930 fps | 99.3% |
| Lovex S071ᴾ | <<locked>> | 100% | 47,819 psi | 79% | 2877 fps | 99.3% |
| Norma 203B | <<locked>> | 82% | 54,897 psi | 90% | 2972 fps | 100% |
| Norma 204 | <<locked>> | 90% | 53,853 psi | 88% | 3002 fps | 98.3% |
| Norma MRP | <<locked>> | 96% | 53,229 psi | 87% | 3091 fps | 99.5% |
| Norma URP | <<locked>> | 90% | 54,447 psi | 89% | 3009 fps | 100% |
| Ramshot Grand | <<locked>> | 98% | 52,040 psi | 85% | 3051 fps | 97.6% |
| Ramshot Hunter | <<locked>> | 90% | 53,026 psi | 87% | 3005 fps | 99.8% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 50,125 psi | 82% | 2986 fps | 98.7% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,231 psi | 61% | 1909 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 82% | 52,881 psi | 87% | 2930 fps | 99.6% |
| ReloadSwiss RS 60 | <<locked>> | 84% | 53,316 psi | 88% | 3035 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 88% | 52,011 psi | 85% | 2989 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 90% | 54,070 psi | 89% | 3077 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 46,050 psi | 76% | 3015 fps | 98.9% |
| Rottweil R 903 | <<locked>> | 84% | 53,098 psi | 87% | 2927 fps | 100% |
| Rottweil R 904 | <<locked>> | 94% | 54,534 psi | 90% | 2982 fps | 97.6% |
| Rottweil R 905 | <<locked>> | 94% | 51,721 psi | 85% | 2986 fps | 98.3% |
| Rottweil R 907 | <<locked>> | 86% | 52,228 psi | 86% | 2913 fps | 98.9% |
| Shooters World Long Rifle | <<locked>> | 88% | 53,954 psi | 89% | 2940 fps | 99.9% |
| Shooters World Precision | <<locked>> | 82% | 54,172 psi | 89% | 2913 fps | 100% |
| Shooters World SW4350 | <<locked>> | 88% | 52,098 psi | 86% | 2930 fps | 99.3% |
| SNPE Vectan SP 11 | <<locked>> | 84% | 54,389 psi | 89% | 2986 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 84% | 53,795 psi | 88% | 2808 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 88% | 53,548 psi | 88% | 2890 fps | 99.4% |
| SNPE Vectan Tubal 8000 | <<locked>> | 96% | 54,853 psi | 90% | 3041 fps | 98.8% |
| Somchem S355 | <<locked>> | 84% | 52,866 psi | 87% | 2920 fps | 100% |
| Somchem S361 | <<locked>> | 92% | 52,649 psi | 86% | 2913 fps | 96.5% |
| Somchem S365 | <<locked>> | 92% | 53,925 psi | 89% | 3009 fps | 100% |
| Somchem S385 | <<locked>> | 94% | 52,402 psi | 86% | 2963 fps | 99% |
| Vihtavuori N150 | <<locked>> | 86% | 54,114 psi | 89% | 2894 fps | 100% |
| Vihtavuori N160 | <<locked>> | 88% | 52,721 psi | 87% | 2943 fps | 100% |
| Vihtavuori N165 | <<locked>> | 98% | 51,648 psi | 85% | 2933 fps | 98.6% |
| Vihtavuori N540 | <<locked>> | 82% | 54,940 psi | 90% | 2894 fps | 100% |
| Vihtavuori N550 | <<locked>> | 88% | 52,098 psi | 86% | 2953 fps | 100% |
| Vihtavuori N555 | <<locked>> | 96% | 53,243 psi | 87% | 3018 fps | 100% |
| Vihtavuori N560 | <<locked>> | 96% | 53,374 psi | 88% | 3077 fps | 97% |
| Vihtavuori N565ᴾ | <<locked>> | 100% | 49,008 psi | 80% | 2982 fps | 96.3% |
| Winchester 6.5 StaBALL | <<locked>> | 88% | 52,170 psi | 86% | 2907 fps | 100% |
| Winchester 760 | <<locked>> | 88% | 54,215 psi | 89% | 3022 fps | 99.5% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 49,922 psi | 82% | 3117 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 96% | 52,286 psi | 86% | 2953 fps | 98.2% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 25.6"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2700 | <<locked>> | 80% | 51,619 psi | 85% | 2864 fps | 98.6% |
| Accurate 3100 | <<locked>> | 84% | 33,460 psi | 55% | 2575 fps | 95.9% |
| Accurate 4064 | <<locked>> | 80% | 51,285 psi | 84% | 2854 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 39,552 psi | 65% | 2733 fps | 99% |
| Accurate High Country | 74.2 gr | 90% | 44,556 psi | 73% | 2930 fps | 95.6% |
| Accurate MAGPRO | <<locked>> | 94% | 48,646 psi | 80% | 2995 fps | 95.2% |
| ADI AR 2208 | <<locked>> | 80% | 48,240 psi | 79% | 2835 fps | 100% |
| ADI AR 2209 | <<locked>> | 86% | 40,770 psi | 67% | 2772 fps | 95.3% |
| ADI AR 2213 | <<locked>> | 94% | 47,456 psi | 78% | 2940 fps | 95.9% |
| ADI AR 2225 | <<locked>> | 98% | 35,157 psi | 58% | 2707 fps | 95.1% |
| Alliant Power Pro Varmint | <<locked>> | 86% | 41,017 psi | 67% | 2776 fps | 95.5% |
| Alliant Power Pro Varmint | <<locked>> | 86% | 41,017 psi | 67% | 2776 fps | 95.5% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 48,907 psi | 80% | 2861 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 38,334 psi | 63% | 2746 fps | 99.1% |
| Alliant Reloder-17 | <<locked>> | 80% | 43,598 psi | 72% | 2871 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 86% | 40,596 psi | 67% | 2769 fps | 95.4% |
| Alliant Reloder-22 | <<locked>> | 90% | 40,915 psi | 67% | 2818 fps | 95.7% |
| Alliant Reloder-23 | <<locked>> | 80% | 28,152 psi | 46% | 2490 fps | 97.3% |
| Alliant Reloder-25 | <<locked>> | 88% | 32,024 psi | 53% | 2618 fps | 95.8% |
| Alliant Reloder-26 | 68 gr | 80% | 30,269 psi | 50% | 2608 fps | 95.9% |
| Bofors RP15 | <<locked>> | 92% | 40,364 psi | 66% | 2805 fps | 95.4% |
| Bofors RP3 | <<locked>> | 80% | 49,385 psi | 81% | 2874 fps | 100% |
| Bofors RP5 | <<locked>> | 90% | 40,915 psi | 67% | 2818 fps | 95.7% |
| Bofors RP7 | <<locked>> | 80% | 43,366 psi | 71% | 2749 fps | 97.3% |
| Hodgdon H1000 | <<locked>> | 98% | 43,482 psi | 71% | 2848 fps | 95.6% |
| Hodgdon H380 | <<locked>> | 80% | 49,661 psi | 82% | 2887 fps | 99.9% |
| Hodgdon H414 | <<locked>> | 80% | 41,466 psi | 68% | 2782 fps | 97.4% |
| Hodgdon H4350 | <<locked>> | 80% | 44,237 psi | 73% | 2802 fps | 96.8% |
| Hodgdon H4831 | <<locked>> | 92% | 47,529 psi | 78% | 2887 fps | 95.3% |
| Hodgdon H4831 SC | <<locked>> | 92% | 46,528 psi | 76% | 2867 fps | 95% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 35,926 psi | 59% | 2631 fps | 99.5% |
| Hodgdon Retumbo | <<locked>> | 96% | 40,422 psi | 66% | 2887 fps | 96.1% |
| Hodgdon Superformance | <<locked>> | 80% | 40,408 psi | 66% | 2792 fps | 96.8% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,354 psi | 45% | 1670 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 50,749 psi | 83% | 2871 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 38,914 psi | 64% | 2671 fps | 96% |
| IMR 4451 Enduron | <<locked>> | 80% | 44,701 psi | 73% | 2776 fps | 98% |
| IMR 4831 | <<locked>> | 80% | 37,898 psi | 62% | 2684 fps | 98.8% |
| IMR 4955 Enduron | <<locked>> | 90% | 46,224 psi | 76% | 2822 fps | 95.1% |
| IMR 7828 SSC | <<locked>> | 94% | 45,310 psi | 74% | 2910 fps | 95.4% |
| Lovex S062 | <<locked>> | 80% | 51,010 psi | 84% | 2864 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 42,134 psi | 69% | 2723 fps | 98.6% |
| Lovex S070 | <<locked>> | 80% | 40,393 psi | 66% | 2703 fps | 97.3% |
| Lovex S071 | <<locked>> | 88% | 32,619 psi | 54% | 2552 fps | 95.5% |
| Norma 203B | <<locked>> | 80% | 51,503 psi | 85% | 2917 fps | 100% |
| Norma 204 | <<locked>> | 82% | 41,104 psi | 67% | 2759 fps | 95.3% |
| Norma MRP | 69.3 gr | 84% | 34,983 psi | 57% | 2707 fps | 95.1% |
| Norma URP | <<locked>> | 80% | 39,131 psi | 64% | 2726 fps | 98.9% |
| Ramshot Grand | <<locked>> | 94% | 45,223 psi | 74% | 2920 fps | 95.8% |
| Ramshot Hunter | <<locked>> | 80% | 38,058 psi | 62% | 2713 fps | 97.3% |
| Ramshot Magnum | <<locked>> | 92% | 37,405 psi | 61% | 2723 fps | 95.2% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,876 psi | 46% | 1709 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 49,632 psi | 81% | 2871 fps | 99.3% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 46,282 psi | 76% | 2920 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 39,276 psi | 64% | 2749 fps | 98.8% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 37,927 psi | 62% | 2759 fps | 98.3% |
| ReloadSwiss RS 76 | <<locked>> | 94% | 37,246 psi | 61% | 2799 fps | 96% |
| Rottweil R 903 | <<locked>> | 80% | 46,499 psi | 76% | 2818 fps | 100% |
| Rottweil R 904 | <<locked>> | 88% | 45,165 psi | 74% | 2812 fps | 95.4% |
| Rottweil R 905 | <<locked>> | 86% | 39,595 psi | 65% | 2746 fps | 95.3% |
| Rottweil R 907 | <<locked>> | 80% | 43,366 psi | 71% | 2749 fps | 97.3% |
| Shooters World Long Rifle | <<locked>> | 80% | 42,134 psi | 69% | 2723 fps | 98.6% |
| Shooters World Precision | <<locked>> | 80% | 51,010 psi | 84% | 2864 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 40,393 psi | 66% | 2703 fps | 97.3% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 47,732 psi | 78% | 2874 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 47,514 psi | 78% | 2713 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 41,350 psi | 68% | 2671 fps | 97.4% |
| SNPE Vectan Tubal 8000 | <<locked>> | 86% | 39,233 psi | 64% | 2740 fps | 95.1% |
| Somchem S355 | <<locked>> | 80% | 46,615 psi | 77% | 2815 fps | 100% |
| Somchem S361 | <<locked>> | 90% | 49,400 psi | 81% | 2858 fps | 95.7% |
| Somchem S365 | <<locked>> | 80% | 35,766 psi | 59% | 2684 fps | 100% |
| Somchem S385 | <<locked>> | 84% | 37,739 psi | 62% | 2674 fps | 95.6% |
| Vihtavuori N150 | <<locked>> | 80% | 44,570 psi | 73% | 2740 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 40,567 psi | 67% | 2723 fps | 99.1% |
| Vihtavuori N165 | <<locked>> | 90% | 39,682 psi | 65% | 2707 fps | 95.8% |
| Vihtavuori N540 | <<locked>> | 80% | 51,576 psi | 85% | 2844 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 40,059 psi | 66% | 2726 fps | 98.9% |
| Vihtavuori N555 | <<locked>> | 80% | 31,328 psi | 51% | 2572 fps | 97.4% |
| Vihtavuori N560 | <<locked>> | 92% | 46,543 psi | 76% | 2949 fps | 95.3% |
| Vihtavuori N565 | <<locked>> | 98% | 45,600 psi | 75% | 2920 fps | 95.4% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 39,624 psi | 65% | 2690 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 41,466 psi | 68% | 2782 fps | 97.4% |
| Winchester StaBALL HD | <<locked>> | 80% | 24,976 psi | 41% | 2467 fps | 96.4% |
| Winchester Supreme 780 | <<locked>> | 88% | 39,537 psi | 65% | 2710 fps | 95% |
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 84 powders for .300 Blaser Mag. loaded with the .308 | 171gr | Viper Bullets Bush Gold. Alliant Reloder-26 delivers the highest muzzle velocity at 3,136 fps; across all powders the maximum-charge window runs from 1,867 fps to 3,136 fps. ADI AR 2225 gives the best case fill at 100 %, and 84 of the 84 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 171.0 gr projectile in 0.308" calls for a 1:15.0 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, Accurate High Country, Norma MRP rank at the top here: for .300 Blaser Mag. with the .308 | 171gr | Viper Bullets Bush Gold 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.