Load Specifications
Bullet:.308 | 136gr | Geco ZERO
Bullet Manufacturer:Geco
Bullet Weight:136 gr
Bullet Diameter:0.308"
Bullet Length:<<locked>>
Caliber:.300 WSM load data
Case Length (l3):2.09"
Cartridge Length (C.O.L.):<<locked>>
Case Capacity:81.3 Grains of Water
Primer Size:Large Rifle Magnum (LRM)
Barrel Length:24"
Max. allowed Pressure:63,817 psi
Recommended Twist Rate:1:12.5
Load data in caliber .300 WSM with .308 | 136gr | Geco ZERO bullet and 104 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are ReloadSwiss RS 60, Alliant Power Pro 2000-MR and ReloadSwiss RS 52.
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>> | 88% | 56,521 psi | 89% | 3097 fps | 100% |
| Accurate 2460 | <<locked>> | 84% | 54,998 psi | 86% | 3120 fps | 100% |
| Accurate 2495 | <<locked>> | 92% | 54,157 psi | 85% | 3107 fps | 100% |
| Accurate 2520 | <<locked>> | 88% | 55,332 psi | 87% | 3169 fps | 100% |
| Accurate 4064 | <<locked>> | 94% | 54,041 psi | 85% | 3150 fps | 100% |
| Accurate 4350ᴾ | <<locked>> | 100% | 50,285 psi | 79% | 3153 fps | 97.9% |
| Accurate LT-30 | <<locked>> | 82% | 55,782 psi | 87% | 3038 fps | 100% |
| Accurate LT-32 | <<locked>> | 82% | 56,188 psi | 88% | 3068 fps | 100% |
| ADI AR 2206H | <<locked>> | 90% | 55,782 psi | 87% | 3192 fps | 99.5% |
| ADI AR 2208 | <<locked>> | 96% | 57,058 psi | 89% | 3189 fps | 99.2% |
| ADI AR 2219 | <<locked>> | 82% | 57,261 psi | 90% | 3173 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 88% | 55,071 psi | 86% | 3146 fps | 99.9% |
| Alliant AR-Comp | <<locked>> | 88% | 55,332 psi | 87% | 3130 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 84% | 56,637 psi | 89% | 3264 fps | 99.8% |
| Alliant Power Pro 2000-MR | <<locked>> | 92% | 55,695 psi | 87% | 3314 fps | 99.2% |
| Alliant Reloder- TS 15.5 | <<locked>> | 96% | 56,492 psi | 89% | 3209 fps | 99.9% |
| Alliant Reloder-10x | <<locked>> | 84% | 56,173 psi | 88% | 3104 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 94% | 57,261 psi | 90% | 3235 fps | 99.4% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 49,371 psi | 77% | 3166 fps | 98.1% |
| Alliant Reloder-17ᴾ | <<locked>> | 100% | 57,711 psi | 90% | 3337 fps | 99.9% |
| Baschieri & Pellagri 106 | <<locked>> | 82% | 55,405 psi | 87% | 3031 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 90% | 55,898 psi | 88% | 3205 fps | 98.9% |
| Bofors RP3 | <<locked>> | 96% | 57,261 psi | 90% | 3228 fps | 99.9% |
| Bofors RP7ᴾ | <<locked>> | 100% | 57,638 psi | 90% | 3182 fps | 96% |
| Hodgdon Benchmark | <<locked>> | 88% | 57,014 psi | 89% | 3133 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 88% | 54,056 psi | 85% | 3173 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 86% | 56,391 psi | 88% | 3281 fps | 99.3% |
| Hodgdon H322 | <<locked>> | 86% | 54,998 psi | 86% | 3140 fps | 100% |
| Hodgdon H335 | <<locked>> | 82% | 56,521 psi | 89% | 3169 fps | 100% |
| Hodgdon H380 | <<locked>> | 94% | 54,853 psi | 86% | 3179 fps | 98.2% |
| Hodgdon H414 | <<locked>> | 98% | 55,956 psi | 88% | 3248 fps | 96.4% |
| Hodgdon H4198 | <<locked>> | 82% | 57,653 psi | 90% | 3094 fps | 100% |
| Hodgdon H4895 | <<locked>> | 90% | 56,304 psi | 88% | 3205 fps | 99.8% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 45,469 psi | 71% | 3035 fps | 98.5% |
| Hodgdon LEVERevolution | <<locked>> | 94% | 55,637 psi | 87% | 3235 fps | 99.9% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 34,679 psi | 54% | 1955 fps | 100% |
| Hodgdon VARGET | <<locked>> | 94% | 56,710 psi | 89% | 3189 fps | 99.7% |
| IMR 3031 | <<locked>> | 94% | 57,667 psi | 90% | 3219 fps | 100% |
| IMR 4064 | <<locked>> | 96% | 55,419 psi | 87% | 3153 fps | 99.2% |
| IMR 4166 Enduron | <<locked>> | 96% | 55,158 psi | 86% | 3117 fps | 96.1% |
| IMR 4198 | <<locked>> | 84% | 56,565 psi | 89% | 3068 fps | 100% |
| IMR 4451 Enduron | <<locked>> | 98% | 56,246 psi | 88% | 3163 fps | 96.2% |
| IMR 4831ᴾ | <<locked>> | 100% | 42,424 psi | 66% | 2982 fps | 96.2% |
| IMR 4895 | <<locked>> | 92% | 55,158 psi | 86% | 3215 fps | 99.5% |
| IMR 8208 XBR | <<locked>> | 88% | 55,071 psi | 86% | 3146 fps | 99.9% |
| Lovex D073.5 | <<locked>> | 84% | 55,027 psi | 86% | 3127 fps | 100% |
| Lovex D073.6 | <<locked>> | 90% | 55,332 psi | 87% | 3169 fps | 100% |
| Lovex S060 | <<locked>> | 90% | 55,782 psi | 87% | 3120 fps | 99.5% |
| Lovex S062 | <<locked>> | 94% | 55,854 psi | 88% | 3166 fps | 99.9% |
| Lovex S065ᴾ | <<locked>> | 100% | 55,071 psi | 86% | 3150 fps | 97.5% |
| Lovex S070ᴾ | <<locked>> | 100% | 52,373 psi | 82% | 3123 fps | 95.8% |
| Norma 201 | <<locked>> | 90% | 54,317 psi | 85% | 3133 fps | 99.9% |
| Norma 202 | <<locked>> | 90% | 54,839 psi | 86% | 3140 fps | 100% |
| Norma 203B | <<locked>> | 94% | 56,376 psi | 88% | 3219 fps | 99.6% |
| Norma URPᴾ | <<locked>> | 100% | 49,995 psi | 78% | 3146 fps | 97.8% |
| Ramshot Big Game | <<locked>> | 94% | 57,290 psi | 90% | 3248 fps | 99.6% |
| Ramshot Hunterᴾ | <<locked>> | 100% | 49,168 psi | 77% | 3133 fps | 95.8% |
| Ramshot TAC | <<locked>> | 88% | 55,680 psi | 87% | 3156 fps | 97.8% |
| Ramshot Wild Boar | <<locked>> | 88% | 54,897 psi | 86% | 3179 fps | 99.4% |
| Ramshot X-Terminator | <<locked>> | 86% | 56,217 psi | 88% | 3143 fps | 99.4% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 35,114 psi | 55% | 2001 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 84% | 54,563 psi | 86% | 3130 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 94% | 55,550 psi | 87% | 3159 fps | 96.9% |
| ReloadSwiss RS 52 | <<locked>> | 90% | 53,896 psi | 84% | 3245 fps | 99% |
| ReloadSwiss RS 60 | <<locked>> | 98% | 57,522 psi | 90% | 3346 fps | 100% |
| ReloadSwiss RS 62ᴾ | <<locked>> | 100% | 50,386 psi | 79% | 3179 fps | 97.7% |
| ReloadSwiss RS 70ᴾ | <<locked>> | 100% | 50,923 psi | 80% | 3202 fps | 97.3% |
| Rottweil R 901 | <<locked>> | 88% | 54,998 psi | 86% | 3120 fps | 100% |
| Rottweil R 902 | <<locked>> | 92% | 54,868 psi | 86% | 3130 fps | 99.9% |
| Rottweil R 903 | <<locked>> | 98% | 56,797 psi | 89% | 3212 fps | 99.8% |
| Rottweil R 907ᴾ | <<locked>> | 100% | 57,638 psi | 90% | 3182 fps | 96% |
| Shooters World Long Rifleᴾ | <<locked>> | 100% | 55,071 psi | 86% | 3150 fps | 97.5% |
| Shooters World Match Rifle | <<locked>> | 90% | 55,332 psi | 87% | 3169 fps | 100% |
| Shooters World Precision | <<locked>> | 94% | 55,854 psi | 88% | 3166 fps | 99.9% |
| Shooters World SW4350ᴾ | <<locked>> | 100% | 52,373 psi | 82% | 3123 fps | 95.8% |
| Shooters World Tactical Rifle | <<locked>> | 82% | 54,462 psi | 85% | 3097 fps | 99.7% |
| SNPE Vectan SP 10 | <<locked>> | 82% | 57,348 psi | 90% | 3179 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 96% | 55,448 psi | 87% | 3225 fps | 99.4% |
| SNPE Vectan SP 3 | <<locked>> | 84% | 57,261 psi | 90% | 3133 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 90% | 57,537 psi | 90% | 3189 fps | 98.5% |
| SNPE Vectan SP 9 | <<locked>> | 90% | 54,360 psi | 85% | 3159 fps | 99.3% |
| SNPE Vectan Tubal 3000 | <<locked>> | 90% | 56,579 psi | 89% | 3084 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 96% | 56,579 psi | 89% | 3074 fps | 100% |
| SNPE Vectan Tubal 7000ᴾ | <<locked>> | 100% | 55,941 psi | 88% | 3104 fps | 96.2% |
| Somchem S321 | <<locked>> | 86% | 56,376 psi | 88% | 3182 fps | 100% |
| Somchem S335 | <<locked>> | 90% | 55,463 psi | 87% | 3074 fps | 100% |
| Somchem S341 | <<locked>> | 90% | 57,072 psi | 89% | 3182 fps | 99.5% |
| Somchem S355 | <<locked>> | 98% | 57,319 psi | 90% | 3212 fps | 99.8% |
| Somchem S365ᴾ | <<locked>> | 100% | 44,570 psi | 70% | 3087 fps | 99.4% |
| Unknown powderᴾ | <<locked>> | 100% | 54,810 psi | 86% | 3222 fps | 98.1% |
| Vihtavuori N120 | <<locked>> | 82% | 57,043 psi | 89% | 2995 fps | 100% |
| Vihtavuori N130 | <<locked>> | 86% | 54,969 psi | 86% | 3035 fps | 100% |
| Vihtavuori N133 | <<locked>> | 92% | 55,550 psi | 87% | 3058 fps | 100% |
| Vihtavuori N135 | <<locked>> | 92% | 54,157 psi | 85% | 3100 fps | 100% |
| Vihtavuori N140 | <<locked>> | 92% | 54,766 psi | 86% | 3110 fps | 100% |
| Vihtavuori N150ᴾ | <<locked>> | 100% | 51,721 psi | 81% | 3084 fps | 99.9% |
| Vihtavuori N160ᴾ | <<locked>> | 100% | 55,593 psi | 87% | 3192 fps | 98.6% |
| Vihtavuori N530 | <<locked>> | 86% | 54,824 psi | 86% | 3156 fps | 99.9% |
| Vihtavuori N540 | <<locked>> | 92% | 54,404 psi | 85% | 3133 fps | 100% |
| Vihtavuori N550ᴾ | <<locked>> | 100% | 55,709 psi | 87% | 3245 fps | 98.6% |
| Winchester 6.5 StaBALLᴾ | <<locked>> | 100% | 53,983 psi | 85% | 3140 fps | 99.7% |
| Winchester 748 | <<locked>> | 86% | 55,941 psi | 88% | 3205 fps | 100% |
| Winchester 760 | <<locked>> | 98% | 55,956 psi | 88% | 3248 fps | 96.4% |
| Winchester StaBALL Match | <<locked>> | 84% | 55,999 psi | 88% | 3196 fps | 99.8% |
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% | 43,859 psi | 69% | 2890 fps | 100% |
| Accurate 2460 | <<locked>> | 80% | 47,950 psi | 75% | 3002 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 36,085 psi | 57% | 2779 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 41,495 psi | 65% | 2923 fps | 99.4% |
| Accurate 4064 | <<locked>> | 80% | 34,113 psi | 53% | 2756 fps | 98.8% |
| Accurate 4350 | <<locked>> | 94% | 40,509 psi | 63% | 2959 fps | 95.5% |
| Accurate LT-30 | <<locked>> | 80% | 52,373 psi | 82% | 2989 fps | 100% |
| Accurate LT-32 | <<locked>> | 80% | 52,765 psi | 83% | 3015 fps | 100% |
| ADI AR 2206H | <<locked>> | 80% | 40,364 psi | 63% | 2894 fps | 96.8% |
| ADI AR 2208 | <<locked>> | 84% | 39,146 psi | 61% | 2841 fps | 95.7% |
| ADI AR 2219 | <<locked>> | 80% | 53,388 psi | 84% | 3114 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 80% | 42,467 psi | 67% | 2913 fps | 98.5% |
| Alliant AR-Comp | <<locked>> | 80% | 42,061 psi | 66% | 2920 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 80% | 49,458 psi | 78% | 3136 fps | 99.1% |
| Alliant Power Pro 2000-MR | 58.7 gr | 82% | 39,305 psi | 62% | 2966 fps | 95.2% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 33,446 psi | 52% | 2736 fps | 95.5% |
| Alliant Reloder-10x | <<locked>> | 80% | 49,632 psi | 78% | 3005 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 82% | 38,783 psi | 61% | 2874 fps | 95.8% |
| Alliant Reloder-16 | <<locked>> | 94% | 40,872 psi | 64% | 2979 fps | 95.7% |
| Alliant Reloder-17 | <<locked>> | 86% | 35,621 psi | 56% | 2874 fps | 95.6% |
| Baschieri & Pellagri 106 | <<locked>> | 80% | 51,779 psi | 81% | 2979 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 39,537 psi | 62% | 2884 fps | 95.3% |
| Bofors RP3 | <<locked>> | 80% | 32,808 psi | 51% | 2733 fps | 95.4% |
| Bofors RP7 | <<locked>> | 98% | 54,114 psi | 85% | 3123 fps | 95.2% |
| Hodgdon Benchmark | <<locked>> | 80% | 44,469 psi | 70% | 2913 fps | 99.2% |
| Hodgdon BL-C2 | <<locked>> | 80% | 40,872 psi | 64% | 2923 fps | 98.7% |
| Hodgdon CFE223 | <<locked>> | 80% | 45,252 psi | 71% | 3077 fps | 97.5% |
| Hodgdon H322 | <<locked>> | 80% | 44,962 psi | 70% | 2969 fps | 100% |
| Hodgdon H335 | <<locked>> | 80% | 52,591 psi | 82% | 3107 fps | 100% |
| Hodgdon H380 | <<locked>> | 86% | 41,713 psi | 65% | 2927 fps | 95.2% |
| Hodgdon H414 | <<locked>> | 96% | 52,170 psi | 82% | 3182 fps | 95.6% |
| Hodgdon H4198 | <<locked>> | 80% | 54,114 psi | 85% | 3041 fps | 100% |
| Hodgdon H4895 | <<locked>> | 80% | 40,683 psi | 64% | 2904 fps | 97.5% |
| Hodgdon Hybrid 100V | <<locked>> | 92% | 34,998 psi | 55% | 2795 fps | 95.5% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 34,519 psi | 54% | 2802 fps | 96% |
| Hodgdon TrailBoss | <<locked>> | 80% | 25,715 psi | 40% | 1749 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 36,347 psi | 57% | 2785 fps | 96.1% |
| IMR 3031 | <<locked>> | 80% | 36,419 psi | 57% | 2838 fps | 99.9% |
| IMR 4064 | <<locked>> | 84% | 38,159 psi | 60% | 2815 fps | 95.6% |
| IMR 4166 Enduron | <<locked>> | 94% | 51,866 psi | 81% | 3061 fps | 95.4% |
| IMR 4198 | <<locked>> | 80% | 50,183 psi | 79% | 2972 fps | 100% |
| IMR 4451 Enduron | <<locked>> | 96% | 52,895 psi | 83% | 3107 fps | 95.5% |
| IMR 4831 | <<locked>> | 98% | 39,697 psi | 62% | 2920 fps | 95.4% |
| IMR 4895 | <<locked>> | 80% | 36,999 psi | 58% | 2844 fps | 95.9% |
| IMR 8208 XBR | <<locked>> | 80% | 42,467 psi | 67% | 2913 fps | 98.5% |
| Lovex D073.5 | <<locked>> | 80% | 47,747 psi | 75% | 3005 fps | 99.7% |
| Lovex D073.6 | <<locked>> | 80% | 39,059 psi | 61% | 2871 fps | 99.1% |
| Lovex S060 | <<locked>> | 80% | 41,002 psi | 64% | 2838 fps | 97.1% |
| Lovex S062 | <<locked>> | 80% | 35,737 psi | 56% | 2769 fps | 96.9% |
| Lovex S065 | <<locked>> | 94% | 45,484 psi | 71% | 2976 fps | 95.3% |
| Lovex S070 | <<locked>> | 98% | 49,182 psi | 77% | 3064 fps | 95% |
| Norma 201 | <<locked>> | 80% | 39,523 psi | 62% | 2848 fps | 97.9% |
| Norma 202 | <<locked>> | 80% | 39,624 psi | 62% | 2861 fps | 99.5% |
| Norma 203B | <<locked>> | 80% | 35,534 psi | 56% | 2795 fps | 95.3% |
| Norma URP | <<locked>> | 94% | 40,843 psi | 64% | 2959 fps | 95.5% |
| Ramshot Big Game | <<locked>> | 82% | 37,768 psi | 59% | 2871 fps | 95.8% |
| Ramshot Hunter | <<locked>> | 98% | 46,195 psi | 72% | 3074 fps | 95% |
| Ramshot TAC | <<locked>> | 82% | 45,571 psi | 71% | 2969 fps | 95.6% |
| Ramshot Wild Boar | <<locked>> | 80% | 41,756 psi | 65% | 2927 fps | 97.2% |
| Ramshot X-Terminator | <<locked>> | 80% | 46,021 psi | 72% | 2963 fps | 98% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,005 psi | 41% | 1795 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 47,877 psi | 75% | 3015 fps | 99.8% |
| ReloadSwiss RS 50 | <<locked>> | 90% | 48,602 psi | 76% | 3035 fps | 95.3% |
| ReloadSwiss RS 52 | 55.5 gr | 80% | 37,652 psi | 59% | 2913 fps | 95.3% |
| ReloadSwiss RS 60 | 56.3 gr | 80% | 30,835 psi | 48% | 2746 fps | 96.1% |
| ReloadSwiss RS 62 | <<locked>> | 94% | 40,466 psi | 63% | 2976 fps | 95.1% |
| ReloadSwiss RS 70 | <<locked>> | 96% | 44,367 psi | 70% | 3064 fps | 95.4% |
| Rottweil R 901 | <<locked>> | 80% | 42,989 psi | 67% | 2904 fps | 99.7% |
| Rottweil R 902 | <<locked>> | 80% | 37,449 psi | 59% | 2789 fps | 97.3% |
| Rottweil R 903 | <<locked>> | 82% | 33,040 psi | 52% | 2733 fps | 95.2% |
| Rottweil R 907 | <<locked>> | 98% | 54,114 psi | 85% | 3123 fps | 95.2% |
| Shooters World Long Rifle | <<locked>> | 94% | 45,484 psi | 71% | 2976 fps | 95.3% |
| Shooters World Match Rifle | <<locked>> | 80% | 39,059 psi | 61% | 2871 fps | 99.1% |
| Shooters World Precision | <<locked>> | 80% | 35,737 psi | 56% | 2769 fps | 96.9% |
| Shooters World SW4350 | <<locked>> | 98% | 49,182 psi | 77% | 3064 fps | 95% |
| Shooters World Tactical Rifle | <<locked>> | 80% | 50,589 psi | 79% | 3031 fps | 99.4% |
| SNPE Vectan SP 10 | <<locked>> | 80% | 53,693 psi | 84% | 3120 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 84% | 36,738 psi | 58% | 2848 fps | 95.5% |
| SNPE Vectan SP 3 | <<locked>> | 80% | 50,517 psi | 79% | 3028 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 82% | 43,526 psi | 68% | 2933 fps | 95.6% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 39,088 psi | 61% | 2858 fps | 96.4% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 41,089 psi | 64% | 2815 fps | 99.7% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 33,852 psi | 53% | 2661 fps | 99.2% |
| SNPE Vectan Tubal 7000 | <<locked>> | 98% | 52,083 psi | 82% | 3038 fps | 95.4% |
| Somchem S321 | <<locked>> | 80% | 45,847 psi | 72% | 2999 fps | 99.2% |
| Somchem S335 | <<locked>> | 80% | 40,698 psi | 64% | 2818 fps | 99.9% |
| Somchem S341 | <<locked>> | 80% | 40,277 psi | 63% | 2874 fps | 96.7% |
| Somchem S355 | <<locked>> | 82% | 34,127 psi | 53% | 2746 fps | 95.3% |
| Somchem S365 | <<locked>> | 90% | 31,821 psi | 50% | 2772 fps | 95.8% |
| Unknown powder | <<locked>> | 92% | 42,032 psi | 66% | 2972 fps | 95% |
| Vihtavuori N120 | <<locked>> | 80% | 53,505 psi | 84% | 2946 fps | 100% |
| Vihtavuori N130 | <<locked>> | 80% | 45,658 psi | 72% | 2887 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 38,682 psi | 61% | 2769 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 36,622 psi | 57% | 2785 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 37,086 psi | 58% | 2782 fps | 99.4% |
| Vihtavuori N150 | <<locked>> | 84% | 30,821 psi | 48% | 2638 fps | 95.7% |
| Vihtavuori N160 | <<locked>> | 92% | 42,308 psi | 66% | 2949 fps | 95.8% |
| Vihtavuori N530 | <<locked>> | 80% | 44,701 psi | 70% | 2972 fps | 99% |
| Vihtavuori N540 | <<locked>> | 80% | 36,709 psi | 58% | 2795 fps | 99% |
| Vihtavuori N550 | <<locked>> | 92% | 42,482 psi | 67% | 2992 fps | 95.8% |
| Winchester 6.5 StaBALL | <<locked>> | 88% | 35,665 psi | 56% | 2766 fps | 95.9% |
| Winchester 748 | <<locked>> | 80% | 45,223 psi | 71% | 3022 fps | 99.5% |
| Winchester 760 | <<locked>> | 96% | 52,170 psi | 82% | 3182 fps | 95.6% |
| Winchester StaBALL Match | <<locked>> | 80% | 48,153 psi | 75% | 3064 fps | 99% |
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 104 powders for .300 WSM loaded with the .308 | 136gr | Geco ZERO. ReloadSwiss RS 60 delivers the highest muzzle velocity at 3,346 fps; across all powders the maximum-charge window runs from 1,955 fps to 3,346 fps. Accurate 4350 gives the best case fill at 100 %, and 104 of the 104 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (440 MPa), the top charges use 54–90 %, leaving at least 10 % headroom. The 136.0 gr projectile in 0.308" calls for a 1:12.5 twist; slower twists will usually not stabilise this weight. Accurate 4350, Alliant Reloder-16, Alliant Reloder-17 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 60, Alliant Power Pro 2000-MR, ReloadSwiss RS 52 rank at the top here: for .300 WSM with the .308 | 136gr | Geco ZERO 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.