Load Specifications
Bullet:.308 | 150gr | Swift A-Frame
Bullet Manufacturer:Swift
Bullet Weight:150 gr
Bullet Diameter:0.308"
Bullet Length:<<locked>>
Caliber:.300 H&H Mag. load data
Case Length (l3):2.85"
Cartridge Length (C.O.L.):<<locked>>
Case Capacity:85.9 Grains of Water
Primer Size:Large Rifle Magnum (LRM)
Barrel Length:24"
Max. allowed Pressure:62,366 psi
Recommended Twist Rate:1:16.0
Load data in caliber .300 H&H Mag. with .308 | 150gr | Swift A-Frame bullet and 95 powders. The key underlying parameters are shown in the table above.
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 2015 | <<locked>> | 82% | 56,115 psi | 90% | 2949 fps | 100% |
| Accurate 2495 | <<locked>> | 86% | 55,724 psi | 89% | 2976 fps | 100% |
| Accurate 2700 | <<locked>> | 86% | 54,085 psi | 87% | 2972 fps | 96.9% |
| Accurate 3100ᴾ | <<locked>> | 100% | 46,586 psi | 75% | 2923 fps | 97.1% |
| Accurate 4064 | <<locked>> | 88% | 55,738 psi | 89% | 3025 fps | 100% |
| Accurate 4350 | <<locked>> | 96% | 56,231 psi | 90% | 3120 fps | 99.7% |
| ADI AR 2206H | <<locked>> | 84% | 55,477 psi | 89% | 3054 fps | 100% |
| ADI AR 2208 | <<locked>> | 88% | 53,127 psi | 85% | 3002 fps | 99.7% |
| ADI AR 2209ᴾ | <<locked>> | 100% | 53,969 psi | 87% | 3091 fps | 95.9% |
| ADI Benchmark 8208 | <<locked>> | 82% | 54,201 psi | 87% | 2999 fps | 100% |
| Alliant AR-Comp | <<locked>> | 82% | 55,666 psi | 89% | 2979 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 86% | 55,593 psi | 89% | 3182 fps | 99.9% |
| Alliant Reloder- TS 15.5 | <<locked>> | 88% | 53,592 psi | 86% | 3028 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 86% | 54,027 psi | 87% | 3048 fps | 99.8% |
| Alliant Reloder-16 | <<locked>> | 96% | 53,563 psi | 86% | 3123 fps | 99.7% |
| Alliant Reloder-17 | <<locked>> | 92% | 54,810 psi | 88% | 3156 fps | 100% |
| Alliant Reloder-19ᴾ | <<locked>> | 100% | 52,968 psi | 85% | 3074 fps | 95.8% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 43,859 psi | 70% | 2953 fps | 99.5% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 49,951 psi | 80% | 3140 fps | 99.1% |
| Baschieri & Pellagri 107 | <<locked>> | 84% | 55,463 psi | 89% | 3068 fps | 99.7% |
| Bofors RP3 | <<locked>> | 88% | 54,157 psi | 87% | 3041 fps | 100% |
| Bofors RP7 | <<locked>> | 92% | 54,012 psi | 87% | 3012 fps | 97.1% |
| Hodgdon Benchmark | <<locked>> | 82% | 55,680 psi | 89% | 2986 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 82% | 54,070 psi | 87% | 3031 fps | 100% |
| Hodgdon H380 | <<locked>> | 88% | 54,853 psi | 88% | 3054 fps | 99.3% |
| Hodgdon H414 | <<locked>> | 94% | 54,984 psi | 88% | 3110 fps | 97.9% |
| Hodgdon H4350 | <<locked>> | 92% | 55,317 psi | 89% | 3071 fps | 96.7% |
| Hodgdon H4895 | <<locked>> | 84% | 56,043 psi | 90% | 3068 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 98% | 53,490 psi | 86% | 3045 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 86% | 56,086 psi | 90% | 3104 fps | 100% |
| Hodgdon Superformance | <<locked>> | 94% | 55,506 psi | 89% | 3146 fps | 97.7% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,911 psi | 58% | 1909 fps | 100% |
| Hodgdon VARGET | <<locked>> | 84% | 53,708 psi | 86% | 3012 fps | 100% |
| IMR 3031 | <<locked>> | 84% | 56,304 psi | 90% | 3048 fps | 100% |
| IMR 4064 | <<locked>> | 88% | 55,970 psi | 90% | 3038 fps | 99.9% |
| IMR 4166 Enduron | <<locked>> | 86% | 55,680 psi | 89% | 3018 fps | 97.9% |
| IMR 4350 | <<locked>> | 96% | 54,607 psi | 88% | 3038 fps | 97.2% |
| IMR 4451 Enduron | <<locked>> | 92% | 55,941 psi | 90% | 3048 fps | 97.9% |
| IMR 4831 | <<locked>> | 96% | 52,968 psi | 85% | 3051 fps | 99.5% |
| IMR 4895 | <<locked>> | 86% | 55,376 psi | 89% | 3081 fps | 100% |
| IMR 8208 XBR | <<locked>> | 82% | 54,201 psi | 87% | 2999 fps | 100% |
| Lovex D073.6 | <<locked>> | 84% | 55,666 psi | 89% | 3031 fps | 100% |
| Lovex S060 | <<locked>> | 84% | 54,578 psi | 88% | 2976 fps | 99.9% |
| Lovex S062 | <<locked>> | 88% | 56,115 psi | 90% | 3038 fps | 100% |
| Lovex S065 | <<locked>> | 94% | 55,448 psi | 89% | 3038 fps | 98.9% |
| Lovex S070 | <<locked>> | 94% | 53,287 psi | 85% | 3022 fps | 97.7% |
| Norma 201 | <<locked>> | 84% | 54,288 psi | 87% | 3002 fps | 100% |
| Norma 202 | <<locked>> | 84% | 54,824 psi | 88% | 2999 fps | 100% |
| Norma 203B | <<locked>> | 86% | 53,243 psi | 85% | 3035 fps | 99.9% |
| Norma 204 | <<locked>> | 96% | 55,376 psi | 89% | 3091 fps | 96.1% |
| Norma MRPᴾ | <<locked>> | 100% | 49,414 psi | 79% | 3087 fps | 96.7% |
| Norma URP | <<locked>> | 96% | 54,882 psi | 88% | 3100 fps | 99.6% |
| Ramshot Big Game | <<locked>> | 86% | 53,853 psi | 86% | 3058 fps | 99.9% |
| Ramshot Hunter | <<locked>> | 96% | 53,853 psi | 86% | 3094 fps | 98.4% |
| Ramshot TAC | <<locked>> | 82% | 54,389 psi | 87% | 3015 fps | 98.9% |
| Ramshot Wild Boar | <<locked>> | 82% | 54,462 psi | 87% | 3038 fps | 99.9% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,506 psi | 59% | 1952 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 88% | 54,998 psi | 88% | 3035 fps | 98.3% |
| ReloadSwiss RS 52 | <<locked>> | 84% | 54,534 psi | 87% | 3117 fps | 99.8% |
| ReloadSwiss RS 60 | <<locked>> | 90% | 54,273 psi | 87% | 3153 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 96% | 56,144 psi | 90% | 3140 fps | 99.6% |
| ReloadSwiss RS 70 | <<locked>> | 96% | 55,129 psi | 88% | 3169 fps | 99.4% |
| Rottweil R 901 | <<locked>> | 82% | 54,984 psi | 88% | 2979 fps | 100% |
| Rottweil R 902 | <<locked>> | 86% | 54,795 psi | 88% | 2999 fps | 100% |
| Rottweil R 903 | <<locked>> | 90% | 54,273 psi | 87% | 3038 fps | 100% |
| Rottweil R 907 | <<locked>> | 92% | 54,012 psi | 87% | 3012 fps | 97.1% |
| Shooters World Long Rifle | <<locked>> | 94% | 55,448 psi | 89% | 3038 fps | 98.9% |
| Shooters World Match Rifle | <<locked>> | 84% | 55,666 psi | 89% | 3031 fps | 100% |
| Shooters World Precision | <<locked>> | 88% | 56,115 psi | 90% | 3038 fps | 100% |
| Shooters World SW4350 | <<locked>> | 94% | 53,287 psi | 85% | 3022 fps | 97.7% |
| SNPE Vectan SP 11 | <<locked>> | 90% | 55,999 psi | 90% | 3100 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 82% | 53,084 psi | 85% | 2995 fps | 99% |
| SNPE Vectan SP 9 | <<locked>> | 84% | 53,896 psi | 86% | 3022 fps | 99.9% |
| SNPE Vectan Tubal 3000 | <<locked>> | 84% | 55,463 psi | 89% | 2936 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 90% | 55,927 psi | 90% | 2933 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 94% | 55,695 psi | 89% | 2992 fps | 97.9% |
| Somchem S335 | <<locked>> | 84% | 54,998 psi | 88% | 2933 fps | 100% |
| Somchem S341 | <<locked>> | 82% | 52,721 psi | 85% | 2986 fps | 99.8% |
| Somchem S355 | <<locked>> | 90% | 54,462 psi | 87% | 3035 fps | 100% |
| Somchem S365 | <<locked>> | 98% | 53,606 psi | 86% | 3107 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 52,765 psi | 85% | 3038 fps | 96.9% |
| Vihtavuori N133 | <<locked>> | 84% | 55,825 psi | 90% | 2920 fps | 100% |
| Vihtavuori N135 | <<locked>> | 86% | 54,911 psi | 88% | 2966 fps | 100% |
| Vihtavuori N140 | <<locked>> | 86% | 55,448 psi | 89% | 2979 fps | 100% |
| Vihtavuori N150 | <<locked>> | 92% | 55,724 psi | 89% | 3009 fps | 100% |
| Vihtavuori N160 | <<locked>> | 94% | 53,722 psi | 86% | 3041 fps | 99.4% |
| Vihtavuori N530 | <<locked>> | 82% | 54,723 psi | 88% | 3002 fps | 100% |
| Vihtavuori N540 | <<locked>> | 86% | 53,534 psi | 86% | 2969 fps | 100% |
| Vihtavuori N550 | <<locked>> | 94% | 52,881 psi | 85% | 3045 fps | 99.2% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 48,965 psi | 79% | 3038 fps | 99.4% |
| Winchester 6.5 StaBALL | <<locked>> | 94% | 53,824 psi | 86% | 3018 fps | 100% |
| Winchester 748 | <<locked>> | 82% | 55,172 psi | 88% | 3054 fps | 100% |
| Winchester 760 | <<locked>> | 94% | 55,230 psi | 89% | 3114 fps | 97.9% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 39,552 psi | 63% | 2972 fps | 99.6% |
| Winchester StaBALL Match | <<locked>> | 84% | 54,056 psi | 87% | 3035 fps | 100% |
Start Load - Barrel Length: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2015 | <<locked>> | 80% | 52,765 psi | 85% | 2900 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 45,759 psi | 73% | 2822 fps | 100% |
| Accurate 2700 | <<locked>> | 82% | 47,558 psi | 76% | 2854 fps | 95.4% |
| Accurate 3100 | <<locked>> | 96% | 40,582 psi | 65% | 2805 fps | 95.4% |
| Accurate 4064 | <<locked>> | 80% | 43,294 psi | 69% | 2818 fps | 100% |
| Accurate 4350 | <<locked>> | 82% | 34,519 psi | 55% | 2684 fps | 95.1% |
| ADI AR 2206H | <<locked>> | 80% | 48,936 psi | 78% | 2943 fps | 99.6% |
| ADI AR 2208 | <<locked>> | 80% | 41,597 psi | 67% | 2779 fps | 98% |
| ADI AR 2209 | <<locked>> | 98% | 50,691 psi | 81% | 3028 fps | 95% |
| ADI Benchmark 8208 | <<locked>> | 80% | 50,981 psi | 82% | 2946 fps | 100% |
| Alliant AR-Comp | <<locked>> | 80% | 52,141 psi | 84% | 2930 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 44,991 psi | 72% | 2982 fps | 98.7% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 41,510 psi | 67% | 2805 fps | 99.1% |
| Alliant Reloder-15 | <<locked>> | 80% | 44,556 psi | 71% | 2874 fps | 98.7% |
| Alliant Reloder-16 | <<locked>> | 82% | 34,374 psi | 55% | 2700 fps | 95.2% |
| Alliant Reloder-17 | <<locked>> | 80% | 36,027 psi | 58% | 2772 fps | 97.7% |
| Alliant Reloder-19 | <<locked>> | 98% | 49,821 psi | 80% | 3015 fps | 95% |
| Alliant Reloder-23 | <<locked>> | 90% | 32,039 psi | 51% | 2657 fps | 96% |
| Alliant Reloder-26 | <<locked>> | 92% | 37,333 psi | 60% | 2858 fps | 95.6% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 48,356 psi | 78% | 2946 fps | 98.9% |
| Bofors RP3 | <<locked>> | 80% | 41,495 psi | 67% | 2812 fps | 99.2% |
| Bofors RP7 | <<locked>> | 88% | 47,616 psi | 76% | 2894 fps | 95.6% |
| Hodgdon Benchmark | <<locked>> | 80% | 52,431 psi | 84% | 2933 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 50,415 psi | 81% | 2972 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 42,221 psi | 68% | 2818 fps | 97.1% |
| Hodgdon H414 | <<locked>> | 88% | 45,049 psi | 72% | 2923 fps | 95.6% |
| Hodgdon H4350 | <<locked>> | 88% | 48,573 psi | 78% | 2949 fps | 95% |
| Hodgdon H4895 | <<locked>> | 80% | 49,443 psi | 79% | 2953 fps | 99.8% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 29,733 psi | 48% | 2536 fps | 95.1% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 45,716 psi | 73% | 2923 fps | 99.7% |
| Hodgdon Superformance | <<locked>> | 90% | 48,124 psi | 77% | 3012 fps | 96% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,658 psi | 43% | 1703 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 47,297 psi | 76% | 2900 fps | 99.6% |
| IMR 3031 | <<locked>> | 80% | 49,487 psi | 79% | 2946 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 43,714 psi | 70% | 2818 fps | 98.6% |
| IMR 4166 Enduron | <<locked>> | 80% | 46,122 psi | 74% | 2841 fps | 95.8% |
| IMR 4350 | <<locked>> | 90% | 45,150 psi | 72% | 2864 fps | 95% |
| IMR 4451 Enduron | <<locked>> | 84% | 43,685 psi | 70% | 2815 fps | 95% |
| IMR 4831 | <<locked>> | 84% | 35,737 psi | 57% | 2700 fps | 95.7% |
| IMR 4895 | <<locked>> | 80% | 45,643 psi | 73% | 2907 fps | 99.2% |
| IMR 8208 XBR | <<locked>> | 80% | 50,981 psi | 82% | 2946 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 48,718 psi | 78% | 2923 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 48,399 psi | 78% | 2871 fps | 99.6% |
| Lovex S062 | <<locked>> | 80% | 43,714 psi | 70% | 2818 fps | 99.6% |
| Lovex S065 | <<locked>> | 82% | 38,261 psi | 61% | 2700 fps | 95% |
| Lovex S070 | <<locked>> | 88% | 44,019 psi | 71% | 2844 fps | 95.5% |
| Norma 201 | <<locked>> | 80% | 47,819 psi | 77% | 2890 fps | 99.9% |
| Norma 202 | <<locked>> | 80% | 48,240 psi | 77% | 2894 fps | 100% |
| Norma 203B | <<locked>> | 80% | 43,918 psi | 70% | 2861 fps | 99% |
| Norma 204 | <<locked>> | 94% | 51,750 psi | 83% | 3028 fps | 95.2% |
| Norma MRP | <<locked>> | 98% | 46,122 psi | 74% | 3022 fps | 95.7% |
| Norma URP | <<locked>> | 82% | 34,679 psi | 56% | 2687 fps | 95.1% |
| Ramshot Big Game | <<locked>> | 80% | 43,758 psi | 70% | 2877 fps | 98.8% |
| Ramshot Hunter | <<locked>> | 88% | 41,147 psi | 66% | 2848 fps | 95.4% |
| Ramshot TAC | <<locked>> | 80% | 51,053 psi | 82% | 2959 fps | 98.4% |
| Ramshot Wild Boar | <<locked>> | 80% | 50,821 psi | 81% | 2979 fps | 99.7% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,093 psi | 43% | 1745 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 42,308 psi | 68% | 2792 fps | 95.5% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 47,500 psi | 76% | 2992 fps | 99.1% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 38,334 psi | 61% | 2844 fps | 99.8% |
| ReloadSwiss RS 62 | <<locked>> | 84% | 36,883 psi | 59% | 2766 fps | 95.6% |
| ReloadSwiss RS 70 | <<locked>> | 86% | 38,986 psi | 63% | 2835 fps | 95.7% |
| Rottweil R 901 | <<locked>> | 80% | 52,011 psi | 83% | 2933 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 45,614 psi | 73% | 2838 fps | 99.8% |
| Rottweil R 903 | <<locked>> | 80% | 38,957 psi | 62% | 2749 fps | 98.5% |
| Rottweil R 907 | <<locked>> | 88% | 47,616 psi | 76% | 2894 fps | 95.6% |
| Shooters World Long Rifle | <<locked>> | 82% | 38,261 psi | 61% | 2700 fps | 95% |
| Shooters World Match Rifle | <<locked>> | 80% | 48,718 psi | 78% | 2923 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 43,714 psi | 70% | 2818 fps | 99.6% |
| Shooters World SW4350 | <<locked>> | 88% | 44,019 psi | 71% | 2844 fps | 95.5% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 40,074 psi | 64% | 2802 fps | 98.1% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 49,487 psi | 79% | 2933 fps | 98.5% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 47,384 psi | 76% | 2907 fps | 99.4% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 48,921 psi | 78% | 2835 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 41,002 psi | 66% | 2690 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 86% | 42,844 psi | 69% | 2756 fps | 95% |
| Somchem S335 | <<locked>> | 80% | 48,617 psi | 78% | 2835 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 49,182 psi | 79% | 2927 fps | 99.6% |
| Somchem S355 | <<locked>> | 80% | 39,624 psi | 64% | 2753 fps | 98.5% |
| Somchem S365 | <<locked>> | 80% | 29,153 psi | 47% | 2575 fps | 96.4% |
| Somchem S385 | <<locked>> | 96% | 46,340 psi | 74% | 2917 fps | 95.2% |
| Vihtavuori N133 | <<locked>> | 80% | 49,327 psi | 79% | 2825 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 45,353 psi | 73% | 2815 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 45,701 psi | 73% | 2822 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 37,724 psi | 60% | 2684 fps | 99.1% |
| Vihtavuori N160 | <<locked>> | 82% | 36,085 psi | 58% | 2690 fps | 95.6% |
| Vihtavuori N530 | <<locked>> | 80% | 51,184 psi | 82% | 2946 fps | 100% |
| Vihtavuori N540 | <<locked>> | 80% | 44,309 psi | 71% | 2812 fps | 100% |
| Vihtavuori N550 | <<locked>> | 82% | 35,723 psi | 57% | 2694 fps | 95.2% |
| Vihtavuori N555 | <<locked>> | 88% | 32,793 psi | 53% | 2684 fps | 95.2% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 33,388 psi | 54% | 2605 fps | 97% |
| Winchester 748 | <<locked>> | 80% | 51,416 psi | 82% | 2992 fps | 100% |
| Winchester 760 | <<locked>> | 88% | 45,252 psi | 73% | 2930 fps | 95.7% |
| Winchester StaBALL HD | <<locked>> | 92% | 30,385 psi | 49% | 2687 fps | 95.7% |
| Winchester StaBALL Match | <<locked>> | 80% | 47,210 psi | 76% | 2913 fps | 99.7% |
ᴾ possible press load - work up slowly to this load while watching for signs of excessive pressure.
This overview compares 116 powders for .300 H&H Mag. loaded with the .308 | 150gr | Swift A-Frame. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 3,182 fps; across all powders the maximum-charge window runs from 1,909 fps to 3,182 fps. Accurate 3100 gives the best case fill at 100 %, and 116 of the 116 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 150.0 gr projectile in 0.308" calls for a 1:16.0 twist; slower twists will usually not stabilise this weight. Accurate 3100, Accurate High Country, Accurate MAGPRO 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. As outliers, Accurate High Country, Accurate MAGPRO, ADI AR 2213 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.