Load Specifications
Load data in caliber .300 Win. Mag. with .308 | 135gr | IBEX Viper bullet and 89 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are ReloadSwiss RS 70, ReloadSwiss RS 60 and Alliant Reloder-17.
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.
A valid access license is required to use the Personalized Load Calculator.
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 2015 | <<locked>> | 82% | 56,246 psi | 90% | 3097 fps | 100% |
| Accurate 2495 | <<locked>> | 84% | 53,214 psi | 85% | 3084 fps | 100% |
| Accurate 2520 | <<locked>> | 82% | 55,361 psi | 89% | 3173 fps | 100% |
| Accurate 2520 | <<locked>> | 82% | 55,361 psi | 89% | 3173 fps | 100% |
| Accurate 2700 | <<locked>> | 90% | 55,013 psi | 88% | 3104 fps | 96% |
| Accurate 3100ᴾ | <<locked>> | 100% | 46,673 psi | 75% | 3054 fps | 96% |
| Accurate 4064 | <<locked>> | 88% | 56,347 psi | 90% | 3182 fps | 100% |
| Accurate 4350 | <<locked>> | 96% | 55,637 psi | 89% | 3251 fps | 99.2% |
| ADI AR 2206H | <<locked>> | 84% | 55,114 psi | 88% | 3196 fps | 99.7% |
| ADI AR 2208 | <<locked>> | 90% | 55,941 psi | 90% | 3192 fps | 99.5% |
| ADI Benchmark 8208 | <<locked>> | 82% | 53,766 psi | 86% | 3140 fps | 99.9% |
| Alliant AR-Comp | <<locked>> | 82% | 54,853 psi | 88% | 3123 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 86% | 54,447 psi | 87% | 3310 fps | 99.4% |
| Alliant Reloder- TS 15.5 | <<locked>> | 90% | 56,391 psi | 90% | 3219 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 86% | 53,635 psi | 86% | 3186 fps | 99.3% |
| Alliant Reloder-16 | <<locked>> | 98% | 55,796 psi | 89% | 3304 fps | 99.5% |
| Alliant Reloder-17 | <<locked>> | 92% | 53,664 psi | 86% | 3284 fps | 99.9% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 43,787 psi | 70% | 3077 fps | 98.8% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 49,240 psi | 79% | 3261 fps | 98.2% |
| Baschieri & Pellagri 107 | <<locked>> | 84% | 54,665 psi | 88% | 3199 fps | 99.2% |
| Bofors RP3 | <<locked>> | 88% | 54,027 psi | 87% | 3182 fps | 99.9% |
| Bofors RP7 | <<locked>> | 92% | 53,679 psi | 86% | 3136 fps | 96% |
| Hodgdon Benchmark | <<locked>> | 82% | 55,288 psi | 89% | 3120 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 82% | 53,751 psi | 86% | 3173 fps | 100% |
| Hodgdon H380 | <<locked>> | 88% | 54,505 psi | 87% | 3186 fps | 98.7% |
| Hodgdon H414 | <<locked>> | 92% | 55,579 psi | 89% | 3261 fps | 97.1% |
| Hodgdon H4895 | <<locked>> | 84% | 55,680 psi | 89% | 3205 fps | 99.9% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 55,999 psi | 90% | 3228 fps | 99.9% |
| Hodgdon LEVERevolution | <<locked>> | 88% | 55,129 psi | 88% | 3238 fps | 100% |
| Hodgdon Superformance | <<locked>> | 94% | 54,563 psi | 87% | 3264 fps | 96.4% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,013 psi | 58% | 2011 fps | 100% |
| Hodgdon VARGET | <<locked>> | 88% | 55,376 psi | 89% | 3186 fps | 99.9% |
| IMR 3031 | <<locked>> | 86% | 54,317 psi | 87% | 3173 fps | 100% |
| IMR 4064 | <<locked>> | 90% | 54,708 psi | 88% | 3159 fps | 99.5% |
| IMR 4166 Enduron | <<locked>> | 90% | 54,027 psi | 87% | 3123 fps | 96.6% |
| IMR 4350 | <<locked>> | 96% | 53,693 psi | 86% | 3159 fps | 96% |
| IMR 4451 Enduron | <<locked>> | 92% | 55,158 psi | 88% | 3169 fps | 96.8% |
| IMR 4831ᴾ | <<locked>> | 100% | 53,185 psi | 85% | 3196 fps | 99% |
| IMR 4895 | <<locked>> | 86% | 54,969 psi | 88% | 3222 fps | 99.7% |
| IMR 8208 XBR | <<locked>> | 82% | 53,766 psi | 86% | 3140 fps | 99.9% |
| Lovex D073.6 | <<locked>> | 84% | 55,535 psi | 89% | 3176 fps | 100% |
| Lovex S060 | <<locked>> | 84% | 54,186 psi | 87% | 3110 fps | 99.6% |
| Lovex S062 | <<locked>> | 88% | 55,898 psi | 90% | 3176 fps | 100% |
| Lovex S065 | <<locked>> | 94% | 55,129 psi | 88% | 3169 fps | 98.1% |
| Lovex S070 | <<locked>> | 96% | 56,304 psi | 90% | 3209 fps | 97.4% |
| Norma 201 | <<locked>> | 84% | 54,244 psi | 87% | 3140 fps | 100% |
| Norma 202 | <<locked>> | 84% | 54,549 psi | 87% | 3143 fps | 100% |
| Norma 203B | <<locked>> | 88% | 56,072 psi | 90% | 3225 fps | 99.8% |
| Norma URP | <<locked>> | 96% | 54,259 psi | 87% | 3235 fps | 99% |
| Ramshot Big Game | <<locked>> | 86% | 53,026 psi | 85% | 3189 fps | 99.5% |
| Ramshot Hunter | <<locked>> | 96% | 52,750 psi | 85% | 3219 fps | 97.4% |
| Ramshot TAC | <<locked>> | 82% | 53,882 psi | 86% | 3143 fps | 98.1% |
| Ramshot Wild Boar | <<locked>> | 82% | 53,911 psi | 86% | 3176 fps | 99.6% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,651 psi | 59% | 2060 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 88% | 54,505 psi | 87% | 3163 fps | 97.4% |
| ReloadSwiss RS 52 | <<locked>> | 84% | 53,766 psi | 86% | 3251 fps | 99.3% |
| ReloadSwiss RS 60 | <<locked>> | 90% | 53,388 psi | 86% | 3291 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 96% | 55,027 psi | 88% | 3268 fps | 98.9% |
| ReloadSwiss RS 70 | <<locked>> | 96% | 53,983 psi | 87% | 3284 fps | 98.6% |
| Rottweil R 901 | <<locked>> | 82% | 55,709 psi | 89% | 3133 fps | 100% |
| Rottweil R 902 | <<locked>> | 86% | 54,926 psi | 88% | 3143 fps | 100% |
| Rottweil R 903 | <<locked>> | 90% | 54,157 psi | 87% | 3179 fps | 99.9% |
| Rottweil R 907 | <<locked>> | 92% | 53,679 psi | 86% | 3136 fps | 96% |
| Shooters World Long Rifle | <<locked>> | 94% | 55,129 psi | 88% | 3169 fps | 98.1% |
| Shooters World Match Rifle | <<locked>> | 84% | 55,535 psi | 89% | 3176 fps | 100% |
| Shooters World Precision | <<locked>> | 88% | 55,898 psi | 90% | 3176 fps | 100% |
| Shooters World SW4350 | <<locked>> | 96% | 56,304 psi | 90% | 3209 fps | 97.4% |
| SNPE Vectan SP 11 | <<locked>> | 90% | 55,085 psi | 88% | 3232 fps | 99.7% |
| SNPE Vectan SP 7 | <<locked>> | 82% | 52,910 psi | 85% | 3127 fps | 98.3% |
| SNPE Vectan SP 9 | <<locked>> | 84% | 53,388 psi | 86% | 3156 fps | 99.6% |
| SNPE Vectan Tubal 3000 | <<locked>> | 84% | 55,013 psi | 88% | 3074 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 90% | 55,361 psi | 89% | 3071 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 94% | 55,259 psi | 89% | 3114 fps | 96.9% |
| Somchem S335 | <<locked>> | 84% | 54,781 psi | 88% | 3074 fps | 100% |
| Somchem S341 | <<locked>> | 84% | 55,782 psi | 89% | 3176 fps | 99.7% |
| Somchem S355 | <<locked>> | 90% | 54,244 psi | 87% | 3176 fps | 99.8% |
| Somchem S365ᴾ | <<locked>> | 100% | 56,028 psi | 90% | 3297 fps | 100% |
| Unknown powder | <<locked>> | 94% | 55,027 psi | 88% | 3238 fps | 98.6% |
| Vihtavuori N133 | <<locked>> | 86% | 54,781 psi | 88% | 3058 fps | 100% |
| Vihtavuori N135 | <<locked>> | 86% | 54,462 psi | 87% | 3107 fps | 100% |
| Vihtavuori N140 | <<locked>> | 86% | 54,114 psi | 87% | 3107 fps | 100% |
| Vihtavuori N150 | <<locked>> | 96% | 55,230 psi | 89% | 3153 fps | 100% |
| Vihtavuori N160 | <<locked>> | 94% | 55,506 psi | 89% | 3209 fps | 99% |
| Vihtavuori N540 | <<locked>> | 86% | 53,896 psi | 86% | 3133 fps | 100% |
| Vihtavuori N550 | <<locked>> | 94% | 56,101 psi | 90% | 3264 fps | 99.1% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 48,385 psi | 78% | 3169 fps | 98.7% |
| Winchester 6.5 StaBALL | <<locked>> | 94% | 52,881 psi | 85% | 3140 fps | 99.9% |
| Winchester 760 | <<locked>> | 92% | 55,579 psi | 89% | 3261 fps | 97.1% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 39,740 psi | 64% | 3091 fps | 98.9% |
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 2015 | <<locked>> | 80% | 53,098 psi | 85% | 3048 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 47,210 psi | 76% | 2982 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 51,706 psi | 83% | 3114 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 51,706 psi | 83% | 3114 fps | 100% |
| Accurate 2700 | <<locked>> | 88% | 51,735 psi | 83% | 3045 fps | 95.2% |
| Accurate 3100 | <<locked>> | 98% | 43,700 psi | 70% | 2995 fps | 95.2% |
| Accurate 4064 | <<locked>> | 80% | 44,570 psi | 71% | 2976 fps | 100% |
| Accurate 4350 | <<locked>> | 84% | 37,753 psi | 61% | 2890 fps | 95.2% |
| ADI AR 2206H | <<locked>> | 80% | 48,733 psi | 78% | 3077 fps | 99% |
| ADI AR 2208 | <<locked>> | 80% | 41,553 psi | 67% | 2907 fps | 97.1% |
| ADI Benchmark 8208 | <<locked>> | 80% | 50,618 psi | 81% | 3081 fps | 99.8% |
| Alliant AR-Comp | <<locked>> | 80% | 51,576 psi | 83% | 3074 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 44,657 psi | 72% | 3110 fps | 97.7% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 41,814 psi | 67% | 2940 fps | 98.6% |
| Alliant Reloder-15 | <<locked>> | 80% | 44,512 psi | 71% | 3005 fps | 97.9% |
| Alliant Reloder-16 | <<locked>> | 86% | 39,030 psi | 63% | 2943 fps | 95.8% |
| Alliant Reloder-17 | 61.8 gr | 80% | 36,347 psi | 58% | 2900 fps | 96.7% |
| Alliant Reloder-23 | <<locked>> | 92% | 34,563 psi | 55% | 2844 fps | 95.9% |
| Alliant Reloder-26 | <<locked>> | 94% | 40,176 psi | 64% | 3048 fps | 95.4% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 47,964 psi | 77% | 3074 fps | 98.1% |
| Bofors RP3 | <<locked>> | 80% | 42,134 psi | 68% | 2953 fps | 98.7% |
| Bofors RP7 | <<locked>> | 90% | 50,691 psi | 81% | 3081 fps | 95.2% |
| Hodgdon Benchmark | <<locked>> | 80% | 52,040 psi | 83% | 3068 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 50,299 psi | 81% | 3114 fps | 99.9% |
| Hodgdon H380 | <<locked>> | 80% | 42,482 psi | 68% | 2949 fps | 96.2% |
| Hodgdon H414 | <<locked>> | 88% | 48,805 psi | 78% | 3133 fps | 95.5% |
| Hodgdon H4895 | <<locked>> | 80% | 49,255 psi | 79% | 3091 fps | 99.4% |
| Hodgdon Hybrid 100V | <<locked>> | 82% | 32,213 psi | 52% | 2720 fps | 95.1% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 42,844 psi | 69% | 3002 fps | 98.8% |
| Hodgdon Superformance | <<locked>> | 92% | 50,749 psi | 81% | 3192 fps | 95.4% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,093 psi | 43% | 1804 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 43,714 psi | 70% | 2963 fps | 98.6% |
| IMR 3031 | <<locked>> | 80% | 45,324 psi | 73% | 3018 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 40,959 psi | 66% | 2887 fps | 97.2% |
| IMR 4166 Enduron | <<locked>> | 86% | 48,269 psi | 77% | 3012 fps | 95.3% |
| IMR 4350 | <<locked>> | 94% | 50,749 psi | 81% | 3104 fps | 95.3% |
| IMR 4451 Enduron | <<locked>> | 88% | 49,052 psi | 79% | 3054 fps | 95.4% |
| IMR 4831 | <<locked>> | 88% | 37,144 psi | 60% | 2858 fps | 95.1% |
| IMR 4895 | <<locked>> | 80% | 45,629 psi | 73% | 3041 fps | 98.6% |
| IMR 8208 XBR | <<locked>> | 80% | 50,618 psi | 81% | 3081 fps | 99.8% |
| Lovex D073.6 | <<locked>> | 80% | 48,776 psi | 78% | 3064 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 48,153 psi | 77% | 3002 fps | 99% |
| Lovex S062 | <<locked>> | 80% | 44,034 psi | 71% | 2956 fps | 99.2% |
| Lovex S065 | <<locked>> | 86% | 43,787 psi | 70% | 2949 fps | 95.6% |
| Lovex S070 | <<locked>> | 90% | 47,108 psi | 76% | 3038 fps | 95.3% |
| Norma 201 | <<locked>> | 80% | 48,356 psi | 78% | 3035 fps | 99.7% |
| Norma 202 | <<locked>> | 80% | 48,370 psi | 78% | 3038 fps | 100% |
| Norma 203B | <<locked>> | 80% | 43,918 psi | 70% | 2995 fps | 98.3% |
| Norma URP | <<locked>> | 86% | 39,697 psi | 64% | 2936 fps | 95.8% |
| Ramshot Big Game | <<locked>> | 80% | 43,598 psi | 70% | 3005 fps | 98.1% |
| Ramshot Hunter | <<locked>> | 90% | 43,859 psi | 70% | 3035 fps | 95.1% |
| Ramshot TAC | <<locked>> | 80% | 50,792 psi | 81% | 3087 fps | 97.5% |
| Ramshot Wild Boar | <<locked>> | 80% | 50,517 psi | 81% | 3114 fps | 99.3% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,398 psi | 44% | 1844 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 82% | 45,223 psi | 73% | 2982 fps | 95.2% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 47,123 psi | 76% | 3123 fps | 98.4% |
| ReloadSwiss RS 60 | 61.8 gr | 80% | 38,493 psi | 62% | 2976 fps | 99.4% |
| ReloadSwiss RS 62 | <<locked>> | 86% | 39,537 psi | 63% | 2959 fps | 95.5% |
| ReloadSwiss RS 70 | 69.1 gr | 88% | 41,727 psi | 67% | 3022 fps | 95.4% |
| Rottweil R 901 | <<locked>> | 80% | 52,620 psi | 84% | 3084 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 46,035 psi | 74% | 2979 fps | 99.4% |
| Rottweil R 903 | <<locked>> | 80% | 39,726 psi | 64% | 2894 fps | 97.9% |
| Rottweil R 907 | <<locked>> | 90% | 50,691 psi | 81% | 3081 fps | 95.2% |
| Shooters World Long Rifle | <<locked>> | 86% | 43,787 psi | 70% | 2949 fps | 95.6% |
| Shooters World Match Rifle | <<locked>> | 80% | 48,776 psi | 78% | 3064 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 44,034 psi | 71% | 2956 fps | 99.2% |
| Shooters World SW4350 | <<locked>> | 90% | 47,108 psi | 76% | 3038 fps | 95.3% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 40,132 psi | 64% | 2936 fps | 97.3% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 49,487 psi | 79% | 3064 fps | 97.7% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 47,268 psi | 76% | 3041 fps | 98.8% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 48,834 psi | 78% | 2972 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 41,075 psi | 66% | 2822 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 90% | 48,950 psi | 78% | 3002 fps | 95.5% |
| Somchem S335 | <<locked>> | 80% | 48,921 psi | 78% | 2976 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 48,921 psi | 78% | 3058 fps | 99% |
| Somchem S355 | <<locked>> | 80% | 40,263 psi | 65% | 2897 fps | 97.9% |
| Somchem S365 | <<locked>> | 80% | 29,878 psi | 48% | 2707 fps | 95.6% |
| Unknown powder | <<locked>> | 84% | 40,132 psi | 64% | 2936 fps | 95.1% |
| Vihtavuori N133 | <<locked>> | 80% | 46,050 psi | 74% | 2913 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 45,440 psi | 73% | 2959 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 45,237 psi | 73% | 2953 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 34,548 psi | 55% | 2730 fps | 97.6% |
| Vihtavuori N160 | <<locked>> | 82% | 37,855 psi | 61% | 2851 fps | 95% |
| Vihtavuori N540 | <<locked>> | 80% | 45,034 psi | 72% | 2976 fps | 100% |
| Vihtavuori N550 | <<locked>> | 82% | 38,508 psi | 62% | 2900 fps | 95.1% |
| Vihtavuori N555 | <<locked>> | 90% | 35,505 psi | 57% | 2877 fps | 95.2% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 33,895 psi | 54% | 2726 fps | 96% |
| Winchester 760 | <<locked>> | 88% | 48,805 psi | 78% | 3133 fps | 95.5% |
| Winchester StaBALL HD | <<locked>> | 94% | 33,069 psi | 53% | 2877 fps | 95.7% |
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 89 powders for .300 Win. Mag. loaded with the .308 | 135gr | IBEX Viper. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 3,310 fps; across all powders the maximum-charge window runs from 2,011 fps to 3,310 fps. Accurate 3100 gives the best case fill at 100 %, and 89 of the 89 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (430 MPa), the top charges use 58–90 %, leaving at least 10 % headroom. The 135.0 gr projectile in 0.308" calls for a 1:11.5 twist; slower twists will usually not stabilise this weight. Accurate 3100, Alliant Reloder-23, Alliant Reloder-26 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. ReloadSwiss RS 70, ReloadSwiss RS 60, Alliant Reloder-17 rank at the top here: for .300 Win. Mag. with the .308 | 135gr | IBEX Viper 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.