Load Specifications
Load data in caliber .300 Weath. Mag. with .308 | 132gr | Brenneke TIG nature bullet and 94 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Alliant Reloder-17, ReloadSwiss RS 60 and Alliant Reloder-16.
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% | 56,217 psi | 88% | 3189 fps | 100% |
| Accurate 2495 | <<locked>> | 86% | 55,434 psi | 87% | 3209 fps | 100% |
| Accurate 2520 | <<locked>> | 82% | 57,217 psi | 90% | 3284 fps | 100% |
| Accurate 2700 | <<locked>> | 86% | 54,317 psi | 85% | 3205 fps | 96.6% |
| Accurate 3100ᴾ | <<locked>> | 100% | 46,978 psi | 74% | 3143 fps | 96.8% |
| Accurate 4064 | <<locked>> | 88% | 55,695 psi | 87% | 3264 fps | 100% |
| Accurate 4350 | <<locked>> | 96% | 56,768 psi | 89% | 3360 fps | 99.6% |
| ADI AR 2206H | <<locked>> | 84% | 55,724 psi | 87% | 3301 fps | 99.9% |
| ADI AR 2208 | <<locked>> | 90% | 57,087 psi | 89% | 3304 fps | 99.8% |
| ADI Benchmark 8208 | <<locked>> | 82% | 54,418 psi | 85% | 3241 fps | 100% |
| Alliant AR-Comp | <<locked>> | 82% | 55,753 psi | 87% | 3222 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 86% | 56,231 psi | 88% | 3435 fps | 99.8% |
| Alliant Reloder- TS 15.5 | <<locked>> | 90% | 57,348 psi | 90% | 3327 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 86% | 54,085 psi | 85% | 3287 fps | 99.7% |
| Alliant Reloder-16 | <<locked>> | 96% | 54,201 psi | 85% | 3369 fps | 99.6% |
| Alliant Reloder-17 | <<locked>> | 92% | 55,434 psi | 87% | 3402 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 44,382 psi | 70% | 3176 fps | 99.3% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 51,053 psi | 80% | 3379 fps | 99% |
| Baschieri & Pellagri 107 | <<locked>> | 84% | 55,956 psi | 88% | 3314 fps | 99.6% |
| Bofors RP3 | <<locked>> | 88% | 54,505 psi | 85% | 3281 fps | 100% |
| Bofors RP7 | <<locked>> | 92% | 54,375 psi | 85% | 3251 fps | 96.8% |
| Hodgdon Benchmark | <<locked>> | 82% | 55,912 psi | 88% | 3228 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 82% | 54,331 psi | 85% | 3271 fps | 100% |
| Hodgdon H380 | <<locked>> | 88% | 55,288 psi | 87% | 3297 fps | 99.2% |
| Hodgdon H414 | <<locked>> | 94% | 55,767 psi | 87% | 3356 fps | 97.8% |
| Hodgdon H4350 | <<locked>> | 92% | 55,782 psi | 87% | 3310 fps | 96.4% |
| Hodgdon H4895 | <<locked>> | 84% | 56,347 psi | 88% | 3310 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 98% | 54,128 psi | 85% | 3284 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 86% | 56,507 psi | 89% | 3346 fps | 100% |
| Hodgdon Superformance | <<locked>> | 94% | 56,478 psi | 89% | 3392 fps | 97.6% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,578 psi | 56% | 2093 fps | 100% |
| Hodgdon VARGET | <<locked>> | 86% | 57,624 psi | 90% | 3317 fps | 100% |
| IMR 3031 | <<locked>> | 84% | 56,536 psi | 89% | 3294 fps | 100% |
| IMR 4064 | <<locked>> | 88% | 56,478 psi | 89% | 3287 fps | 99.8% |
| IMR 4166 Enduron | <<locked>> | 86% | 55,927 psi | 88% | 3258 fps | 97.7% |
| IMR 4350 | <<locked>> | 96% | 55,259 psi | 87% | 3278 fps | 97.1% |
| IMR 4451 Enduron | <<locked>> | 92% | 56,289 psi | 88% | 3287 fps | 97.7% |
| IMR 4831 | <<locked>> | 98% | 57,450 psi | 90% | 3353 fps | 99.7% |
| IMR 4895 | <<locked>> | 86% | 55,521 psi | 87% | 3323 fps | 99.9% |
| IMR 8208 XBR | <<locked>> | 82% | 54,418 psi | 85% | 3241 fps | 100% |
| Lovex D073.6 | <<locked>> | 84% | 55,796 psi | 87% | 3271 fps | 100% |
| Lovex S060 | <<locked>> | 84% | 54,839 psi | 86% | 3222 fps | 99.9% |
| Lovex S062 | <<locked>> | 88% | 56,260 psi | 88% | 3278 fps | 100% |
| Lovex S065 | <<locked>> | 94% | 55,941 psi | 88% | 3278 fps | 98.7% |
| Lovex S070 | <<locked>> | 96% | 57,232 psi | 90% | 3320 fps | 98.1% |
| Norma 201 | <<locked>> | 84% | 54,273 psi | 85% | 3238 fps | 100% |
| Norma 202 | <<locked>> | 84% | 54,897 psi | 86% | 3238 fps | 100% |
| Norma 203B | <<locked>> | 88% | 57,058 psi | 89% | 3337 fps | 100% |
| Norma 204 | <<locked>> | 96% | 56,115 psi | 88% | 3333 fps | 95.9% |
| Norma MRPᴾ | <<locked>> | 100% | 50,386 psi | 79% | 3327 fps | 96.5% |
| Norma URP | <<locked>> | 96% | 55,767 psi | 87% | 3346 fps | 99.5% |
| Ramshot Big Game | <<locked>> | 86% | 54,360 psi | 85% | 3301 fps | 99.8% |
| Ramshot Hunter | <<locked>> | 96% | 54,563 psi | 86% | 3337 fps | 98.3% |
| Ramshot TAC | <<locked>> | 82% | 54,694 psi | 86% | 3255 fps | 98.7% |
| Ramshot Wild Boar | <<locked>> | 82% | 54,708 psi | 86% | 3281 fps | 99.9% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,187 psi | 57% | 2142 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 88% | 55,434 psi | 87% | 3274 fps | 98.1% |
| ReloadSwiss RS 52 | <<locked>> | 84% | 54,795 psi | 86% | 3360 fps | 99.7% |
| ReloadSwiss RS 60 | <<locked>> | 90% | 55,071 psi | 86% | 3402 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 96% | 56,855 psi | 89% | 3383 fps | 99.5% |
| ReloadSwiss RS 70 | <<locked>> | 96% | 55,941 psi | 88% | 3415 fps | 99.4% |
| Rottweil R 901 | <<locked>> | 82% | 54,737 psi | 86% | 3219 fps | 100% |
| Rottweil R 902 | <<locked>> | 86% | 54,853 psi | 86% | 3238 fps | 100% |
| Rottweil R 903 | <<locked>> | 90% | 54,346 psi | 85% | 3271 fps | 100% |
| Rottweil R 907 | <<locked>> | 92% | 54,375 psi | 85% | 3251 fps | 96.8% |
| Shooters World Long Rifle | <<locked>> | 94% | 55,941 psi | 88% | 3278 fps | 98.7% |
| Shooters World Match Rifle | <<locked>> | 84% | 55,796 psi | 87% | 3271 fps | 100% |
| Shooters World Precision | <<locked>> | 88% | 56,260 psi | 88% | 3278 fps | 100% |
| Shooters World SW4350 | <<locked>> | 96% | 57,232 psi | 90% | 3320 fps | 98.1% |
| SNPE Vectan SP 11 | <<locked>> | 90% | 56,550 psi | 89% | 3343 fps | 99.9% |
| SNPE Vectan SP 7 | <<locked>> | 84% | 57,087 psi | 89% | 3297 fps | 99.3% |
| SNPE Vectan SP 9 | <<locked>> | 84% | 54,143 psi | 85% | 3261 fps | 99.8% |
| SNPE Vectan Tubal 3000 | <<locked>> | 84% | 55,463 psi | 87% | 3176 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 90% | 56,289 psi | 88% | 3173 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 94% | 55,956 psi | 88% | 3225 fps | 97.7% |
| Somchem S335 | <<locked>> | 84% | 55,056 psi | 86% | 3169 fps | 100% |
| Somchem S341 | <<locked>> | 84% | 56,985 psi | 89% | 3287 fps | 99.9% |
| Somchem S355 | <<locked>> | 90% | 54,563 psi | 86% | 3271 fps | 100% |
| Somchem S365 | <<locked>> | 98% | 54,288 psi | 85% | 3346 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 53,403 psi | 84% | 3271 fps | 96.7% |
| Vihtavuori N133 | <<locked>> | 84% | 55,898 psi | 88% | 3159 fps | 100% |
| Vihtavuori N135 | <<locked>> | 86% | 55,013 psi | 86% | 3205 fps | 100% |
| Vihtavuori N140 | <<locked>> | 86% | 55,753 psi | 87% | 3219 fps | 100% |
| Vihtavuori N150 | <<locked>> | 92% | 56,275 psi | 88% | 3251 fps | 100% |
| Vihtavuori N160 | <<locked>> | 94% | 54,418 psi | 85% | 3281 fps | 99.3% |
| Vihtavuori N530 | <<locked>> | 82% | 54,984 psi | 86% | 3245 fps | 100% |
| Vihtavuori N540 | <<locked>> | 88% | 57,624 psi | 90% | 3264 fps | 100% |
| Vihtavuori N550 | <<locked>> | 96% | 57,290 psi | 90% | 3346 fps | 99.5% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 49,472 psi | 78% | 3268 fps | 99.2% |
| Winchester 6.5 StaBALL | <<locked>> | 94% | 54,578 psi | 86% | 3255 fps | 100% |
| Winchester 748 | <<locked>> | 82% | 55,405 psi | 87% | 3294 fps | 100% |
| Winchester 760 | <<locked>> | 94% | 55,985 psi | 88% | 3360 fps | 97.8% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 40,045 psi | 63% | 3192 fps | 99.5% |
| Winchester StaBALL Match | <<locked>> | 84% | 54,375 psi | 85% | 3271 fps | 100% |
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% | 52,707 psi | 83% | 3136 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 45,165 psi | 71% | 3038 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 53,461 psi | 84% | 3225 fps | 100% |
| Accurate 2700 | <<locked>> | 84% | 50,821 psi | 80% | 3143 fps | 95.8% |
| Accurate 3100 | <<locked>> | 98% | 43,830 psi | 69% | 3077 fps | 95.9% |
| Accurate 4064 | <<locked>> | 80% | 42,772 psi | 67% | 3031 fps | 100% |
| Accurate 4350 | <<locked>> | 84% | 36,912 psi | 58% | 2949 fps | 95.5% |
| ADI AR 2206H | <<locked>> | 80% | 48,936 psi | 77% | 3176 fps | 99.4% |
| ADI AR 2208 | <<locked>> | 80% | 41,423 psi | 65% | 2995 fps | 97.6% |
| ADI Benchmark 8208 | <<locked>> | 80% | 51,111 psi | 80% | 3186 fps | 100% |
| Alliant AR-Comp | <<locked>> | 80% | 52,112 psi | 82% | 3166 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 45,252 psi | 71% | 3215 fps | 98.4% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 41,452 psi | 65% | 3022 fps | 98.8% |
| Alliant Reloder-15 | <<locked>> | 80% | 44,498 psi | 70% | 3097 fps | 98.3% |
| Alliant Reloder-16 | 67.9 gr | 84% | 36,579 psi | 57% | 2969 fps | 95.5% |
| Alliant Reloder-17 | 69.6 gr | 80% | 36,071 psi | 57% | 2979 fps | 97.2% |
| Alliant Reloder-23 | <<locked>> | 90% | 31,879 psi | 50% | 2848 fps | 95.3% |
| Alliant Reloder-26 | <<locked>> | 92% | 37,594 psi | 59% | 3064 fps | 95.2% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 48,631 psi | 76% | 3176 fps | 98.7% |
| Bofors RP3 | <<locked>> | 80% | 41,292 psi | 65% | 3022 fps | 98.9% |
| Bofors RP7 | <<locked>> | 88% | 47,703 psi | 75% | 3117 fps | 95.2% |
| Hodgdon Benchmark | <<locked>> | 80% | 52,373 psi | 82% | 3166 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 50,604 psi | 79% | 3205 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 41,989 psi | 66% | 3028 fps | 96.6% |
| Hodgdon H414 | <<locked>> | 88% | 45,382 psi | 71% | 3150 fps | 95.2% |
| Hodgdon H4350 | <<locked>> | 90% | 52,373 psi | 82% | 3251 fps | 95.7% |
| Hodgdon H4895 | <<locked>> | 80% | 49,487 psi | 78% | 3189 fps | 99.7% |
| Hodgdon Hybrid 100V | <<locked>> | 82% | 31,444 psi | 49% | 2782 fps | 95.3% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 45,818 psi | 72% | 3153 fps | 99.5% |
| Hodgdon Superformance | <<locked>> | 90% | 48,747 psi | 76% | 3245 fps | 95.8% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,556 psi | 42% | 1877 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 47,282 psi | 74% | 3130 fps | 99.5% |
| IMR 3031 | <<locked>> | 80% | 49,458 psi | 78% | 3179 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 43,526 psi | 68% | 3038 fps | 98.2% |
| IMR 4166 Enduron | <<locked>> | 80% | 46,035 psi | 72% | 3064 fps | 95.4% |
| IMR 4350 | <<locked>> | 92% | 48,588 psi | 76% | 3156 fps | 95.5% |
| IMR 4451 Enduron | <<locked>> | 86% | 46,586 psi | 73% | 3100 fps | 95.4% |
| IMR 4831 | <<locked>> | 84% | 35,563 psi | 56% | 2897 fps | 95.1% |
| IMR 4895 | <<locked>> | 80% | 45,658 psi | 72% | 3133 fps | 99% |
| IMR 8208 XBR | <<locked>> | 80% | 51,111 psi | 80% | 3186 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 48,573 psi | 76% | 3150 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 48,472 psi | 76% | 3104 fps | 99.4% |
| Lovex S062 | <<locked>> | 80% | 43,584 psi | 68% | 3041 fps | 99.4% |
| Lovex S065 | <<locked>> | 84% | 40,712 psi | 64% | 2969 fps | 95.3% |
| Lovex S070 | <<locked>> | 88% | 44,092 psi | 69% | 3064 fps | 95.1% |
| Norma 201 | <<locked>> | 80% | 47,572 psi | 75% | 3117 fps | 99.8% |
| Norma 202 | <<locked>> | 80% | 48,312 psi | 76% | 3127 fps | 100% |
| Norma 203B | <<locked>> | 80% | 43,845 psi | 69% | 3084 fps | 98.6% |
| Norma 204 | <<locked>> | 94% | 52,359 psi | 82% | 3264 fps | 95% |
| Norma MRP | <<locked>> | 98% | 46,688 psi | 73% | 3251 fps | 95.5% |
| Norma URP | <<locked>> | 84% | 36,985 psi | 58% | 2949 fps | 95.3% |
| Ramshot Big Game | <<locked>> | 80% | 43,918 psi | 69% | 3097 fps | 98.5% |
| Ramshot Hunter | <<locked>> | 88% | 41,495 psi | 65% | 3068 fps | 95% |
| Ramshot TAC | <<locked>> | 80% | 51,300 psi | 80% | 3196 fps | 98.2% |
| Ramshot Wild Boar | <<locked>> | 80% | 51,010 psi | 80% | 3215 fps | 99.6% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,861 psi | 42% | 1919 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 42,293 psi | 66% | 3009 fps | 95% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 47,558 psi | 75% | 3222 fps | 98.8% |
| ReloadSwiss RS 60 | 69.6 gr | 80% | 38,421 psi | 60% | 3061 fps | 99.6% |
| ReloadSwiss RS 62 | <<locked>> | 84% | 36,825 psi | 58% | 2969 fps | 95% |
| ReloadSwiss RS 70 | <<locked>> | 86% | 39,131 psi | 61% | 3048 fps | 95.2% |
| Rottweil R 901 | <<locked>> | 80% | 51,401 psi | 81% | 3163 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 45,324 psi | 71% | 3061 fps | 99.6% |
| Rottweil R 903 | <<locked>> | 80% | 38,653 psi | 61% | 2956 fps | 98.1% |
| Rottweil R 907 | <<locked>> | 88% | 47,703 psi | 75% | 3117 fps | 95.2% |
| Shooters World Long Rifle | <<locked>> | 84% | 40,712 psi | 64% | 2969 fps | 95.3% |
| Shooters World Match Rifle | <<locked>> | 80% | 48,573 psi | 76% | 3150 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 43,584 psi | 68% | 3041 fps | 99.4% |
| Shooters World SW4350 | <<locked>> | 88% | 44,092 psi | 69% | 3064 fps | 95.1% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 40,030 psi | 63% | 3015 fps | 97.7% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 49,661 psi | 78% | 3163 fps | 98.3% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 47,442 psi | 74% | 3136 fps | 99.2% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 48,921 psi | 77% | 3068 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 40,959 psi | 64% | 2907 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 88% | 45,919 psi | 72% | 3035 fps | 95.5% |
| Somchem S335 | <<locked>> | 80% | 48,457 psi | 76% | 3061 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 49,472 psi | 78% | 3156 fps | 99.4% |
| Somchem S355 | <<locked>> | 80% | 39,378 psi | 62% | 2963 fps | 98.1% |
| Somchem S365 | <<locked>> | 80% | 28,790 psi | 45% | 2756 fps | 95.5% |
| Somchem S385 | <<locked>> | 98% | 50,053 psi | 78% | 3205 fps | 95.9% |
| Vihtavuori N133 | <<locked>> | 80% | 49,414 psi | 77% | 3058 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 45,266 psi | 71% | 3041 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 45,687 psi | 72% | 3048 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 37,536 psi | 59% | 2890 fps | 98.8% |
| Vihtavuori N160 | <<locked>> | 84% | 38,667 psi | 61% | 2963 fps | 96% |
| Vihtavuori N530 | <<locked>> | 80% | 51,343 psi | 80% | 3182 fps | 100% |
| Vihtavuori N540 | <<locked>> | 80% | 44,208 psi | 69% | 3031 fps | 100% |
| Vihtavuori N550 | <<locked>> | 84% | 38,087 psi | 60% | 2956 fps | 95.5% |
| Vihtavuori N555 | <<locked>> | 90% | 35,041 psi | 55% | 2936 fps | 95.4% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 33,344 psi | 52% | 2799 fps | 96.5% |
| Winchester 748 | <<locked>> | 80% | 51,735 psi | 81% | 3235 fps | 100% |
| Winchester 760 | <<locked>> | 88% | 45,571 psi | 71% | 3153 fps | 95.3% |
| Winchester StaBALL HD | <<locked>> | 94% | 32,401 psi | 51% | 2949 fps | 96.4% |
| Winchester StaBALL Match | <<locked>> | 80% | 47,340 psi | 74% | 3143 fps | 99.5% |
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 113 powders for .300 Weath. Mag. loaded with the .308 | 132gr | Brenneke TIG nature. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 3,435 fps; across all powders the maximum-charge window runs from 2,093 fps to 3,435 fps. Accurate 3100 gives the best case fill at 100 %, and 113 of the 113 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (440 MPa), the top charges use 56–90 %, leaving at least 10 % headroom. The 132.0 gr projectile in 0.308" calls for a 1:11.5 twist; slower twists will usually not stabilise this weight. Accurate 3100, ADI AR 2209, ADI AR 2213 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-17, ReloadSwiss RS 60, Alliant Reloder-16 rank at the top here: for .300 Weath. Mag. with the .308 | 132gr | Brenneke TIG nature they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, ADI AR 2213, Alliant Reloder-22, Alliant Reloder-25 burn incompletely and react more sensitively to barrel length and temperature. Always begin at the start load and work up in small increments while checking case and primer for pressure signs.