Load Specifications
Load data in caliber 6 mm GT with .243 | 105gr | Geco SOFTPOINT bullet and 95 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Alliant Power Pro 2000-MR, Hodgdon Superformance 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>> | 84% | 54,665 psi | 88% | 2707 fps | 100% |
| Accurate 2495 | <<locked>> | 88% | 53,026 psi | 86% | 2726 fps | 100% |
| Accurate 2520 | <<locked>> | 84% | 55,187 psi | 89% | 2795 fps | 100% |
| Accurate 2700 | <<locked>> | 90% | 55,796 psi | 90% | 2772 fps | 97.1% |
| Accurate 4064 | <<locked>> | 90% | 53,388 psi | 86% | 2776 fps | 100% |
| Accurate 4350 | <<locked>> | 98% | 52,866 psi | 85% | 2854 fps | 99.5% |
| ADI AR 2206H | <<locked>> | 86% | 53,751 psi | 87% | 2805 fps | 99.9% |
| ADI AR 2208 | <<locked>> | 92% | 54,592 psi | 88% | 2802 fps | 99.8% |
| ADI Benchmark 8208 | <<locked>> | 84% | 52,953 psi | 85% | 2759 fps | 100% |
| Alliant AR-Comp | <<locked>> | 84% | 53,330 psi | 86% | 2730 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 88% | 53,229 psi | 86% | 2920 fps | 99.8% |
| Alliant Reloder- TS 15.5 | <<locked>> | 92% | 54,810 psi | 88% | 2828 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 90% | 55,288 psi | 89% | 2848 fps | 99.9% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 53,896 psi | 87% | 2904 fps | 99.8% |
| Alliant Reloder-17 | <<locked>> | 96% | 55,492 psi | 90% | 2949 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 38,653 psi | 62% | 2644 fps | 98.6% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 43,120 psi | 70% | 2802 fps | 97.8% |
| Baschieri & Pellagri 107 | <<locked>> | 86% | 53,258 psi | 86% | 2815 fps | 99.5% |
| Bofors RP3 | <<locked>> | 92% | 55,216 psi | 89% | 2841 fps | 100% |
| Bofors RP7 | <<locked>> | 96% | 55,593 psi | 90% | 2812 fps | 97.3% |
| Hodgdon Benchmark | <<locked>> | 84% | 54,621 psi | 88% | 2740 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 86% | 55,637 psi | 90% | 2838 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 82% | 53,954 psi | 87% | 2884 fps | 99.8% |
| Hodgdon H380 | <<locked>> | 90% | 52,663 psi | 85% | 2799 fps | 99.1% |
| Hodgdon H414 | <<locked>> | 98% | 55,637 psi | 90% | 2904 fps | 98.1% |
| Hodgdon H4350 | <<locked>> | 94% | 53,185 psi | 86% | 2815 fps | 96.2% |
| Hodgdon H4895 | <<locked>> | 86% | 54,259 psi | 88% | 2815 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 50,328 psi | 81% | 2785 fps | 99.9% |
| Hodgdon LEVERevolution | <<locked>> | 88% | 53,505 psi | 86% | 2844 fps | 100% |
| Hodgdon Superformance | <<locked>> | 96% | 52,649 psi | 85% | 2877 fps | 97.1% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,317 psi | 57% | 1709 fps | 100% |
| Hodgdon VARGET | <<locked>> | 88% | 55,274 psi | 89% | 2815 fps | 100% |
| IMR 3031 | <<locked>> | 86% | 54,085 psi | 87% | 2795 fps | 100% |
| IMR 4064 | <<locked>> | 90% | 54,201 psi | 87% | 2785 fps | 99.8% |
| IMR 4166 Enduron | <<locked>> | 88% | 54,404 psi | 88% | 2769 fps | 97.7% |
| IMR 4350ᴾ | <<locked>> | 100% | 55,506 psi | 90% | 2835 fps | 97.4% |
| IMR 4451 Enduron | <<locked>> | 94% | 54,114 psi | 87% | 2792 fps | 97.5% |
| IMR 4831ᴾ | <<locked>> | 100% | 53,447 psi | 86% | 2844 fps | 99.6% |
| IMR 4895 | <<locked>> | 88% | 52,982 psi | 85% | 2822 fps | 99.9% |
| IMR 8208 XBR | <<locked>> | 84% | 52,953 psi | 85% | 2759 fps | 100% |
| Lovex D073.6 | <<locked>> | 86% | 53,490 psi | 86% | 2782 fps | 100% |
| Lovex S060 | <<locked>> | 86% | 53,272 psi | 86% | 2733 fps | 99.9% |
| Lovex S062 | <<locked>> | 90% | 54,143 psi | 87% | 2785 fps | 100% |
| Lovex S065 | <<locked>> | 96% | 53,055 psi | 86% | 2782 fps | 98.6% |
| Lovex S070 | <<locked>> | 98% | 54,172 psi | 87% | 2818 fps | 97.9% |
| Norma 201 | <<locked>> | 88% | 55,695 psi | 90% | 2799 fps | 100% |
| Norma 202 | <<locked>> | 86% | 53,098 psi | 86% | 2756 fps | 100% |
| Norma 203B | <<locked>> | 90% | 54,491 psi | 88% | 2835 fps | 100% |
| Norma URPᴾ | <<locked>> | 100% | 55,347 psi | 89% | 2890 fps | 99.6% |
| Ramshot Big Game | <<locked>> | 90% | 55,085 psi | 89% | 2861 fps | 99.9% |
| Ramshot Hunterᴾ | <<locked>> | 100% | 54,099 psi | 87% | 2887 fps | 98.5% |
| Ramshot TAC | <<locked>> | 84% | 52,924 psi | 85% | 2772 fps | 98.7% |
| Ramshot Wild Boar | <<locked>> | 84% | 52,504 psi | 85% | 2792 fps | 99.9% |
| Ramshot X-Terminator | <<locked>> | 82% | 53,708 psi | 87% | 2759 fps | 99.9% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,013 psi | 58% | 1755 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 82% | 55,593 psi | 90% | 2785 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 90% | 52,881 psi | 85% | 2779 fps | 98% |
| ReloadSwiss RS 52 | <<locked>> | 88% | 55,637 psi | 90% | 2913 fps | 99.9% |
| ReloadSwiss RS 60 | <<locked>> | 94% | 55,216 psi | 89% | 2949 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 98% | 52,301 psi | 84% | 2871 fps | 99.3% |
| ReloadSwiss RS 70ᴾ | <<locked>> | 100% | 55,680 psi | 90% | 2953 fps | 99.5% |
| Rottweil R 901 | <<locked>> | 84% | 53,664 psi | 87% | 2733 fps | 100% |
| Rottweil R 902 | <<locked>> | 88% | 53,200 psi | 86% | 2753 fps | 100% |
| Rottweil R 903 | <<locked>> | 94% | 55,085 psi | 89% | 2831 fps | 100% |
| Rottweil R 907 | <<locked>> | 96% | 55,593 psi | 90% | 2812 fps | 97.3% |
| Shooters World Long Rifle | <<locked>> | 96% | 53,055 psi | 86% | 2782 fps | 98.6% |
| Shooters World Match Rifle | <<locked>> | 86% | 53,490 psi | 86% | 2782 fps | 100% |
| Shooters World Precision | <<locked>> | 90% | 54,143 psi | 87% | 2785 fps | 100% |
| Shooters World SW4350 | <<locked>> | 98% | 54,172 psi | 87% | 2818 fps | 97.9% |
| SNPE Vectan SP 11 | <<locked>> | 92% | 53,476 psi | 86% | 2844 fps | 99.9% |
| SNPE Vectan SP 7 | <<locked>> | 86% | 54,781 psi | 88% | 2802 fps | 99.2% |
| SNPE Vectan SP 9 | <<locked>> | 88% | 55,492 psi | 90% | 2825 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 86% | 54,288 psi | 88% | 2694 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 92% | 54,375 psi | 88% | 2694 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 96% | 53,519 psi | 86% | 2736 fps | 97.5% |
| Somchem S321 | <<locked>> | 82% | 53,693 psi | 87% | 2785 fps | 100% |
| Somchem S335 | <<locked>> | 86% | 53,417 psi | 86% | 2690 fps | 100% |
| Somchem S341 | <<locked>> | 86% | 54,360 psi | 88% | 2792 fps | 99.9% |
| Somchem S355 | <<locked>> | 94% | 55,317 psi | 89% | 2828 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 49,719 psi | 80% | 2841 fps | 100% |
| Vihtavuori N130 | <<locked>> | 82% | 54,056 psi | 87% | 2657 fps | 100% |
| Vihtavuori N133 | <<locked>> | 86% | 54,505 psi | 88% | 2680 fps | 100% |
| Vihtavuori N135 | <<locked>> | 88% | 52,881 psi | 85% | 2720 fps | 100% |
| Vihtavuori N140 | <<locked>> | 88% | 53,577 psi | 86% | 2733 fps | 100% |
| Vihtavuori N150 | <<locked>> | 94% | 53,403 psi | 86% | 2759 fps | 100% |
| Vihtavuori N160 | <<locked>> | 98% | 54,592 psi | 88% | 2841 fps | 99.5% |
| Vihtavuori N530 | <<locked>> | 84% | 53,200 psi | 86% | 2756 fps | 100% |
| Vihtavuori N540 | <<locked>> | 90% | 55,013 psi | 89% | 2776 fps | 100% |
| Vihtavuori N550 | <<locked>> | 98% | 53,650 psi | 87% | 2844 fps | 99.3% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 42,264 psi | 68% | 2723 fps | 98.5% |
| Winchester 6.5 StaBALL | <<locked>> | 98% | 54,636 psi | 88% | 2815 fps | 100% |
| Winchester 748 | <<locked>> | 84% | 52,924 psi | 85% | 2799 fps | 100% |
| Winchester 760 | <<locked>> | 98% | 56,101 psi | 90% | 2910 fps | 98.1% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 34,519 psi | 56% | 2638 fps | 98.3% |
| Winchester StaBALL Match | <<locked>> | 88% | 55,332 psi | 89% | 2831 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% | 48,428 psi | 78% | 2618 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 40,959 psi | 66% | 2543 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 48,037 psi | 77% | 2690 fps | 100% |
| Accurate 2700 | <<locked>> | 86% | 49,211 psi | 79% | 2671 fps | 95.8% |
| Accurate 4064 | <<locked>> | 80% | 38,696 psi | 62% | 2536 fps | 100% |
| Accurate 4350 | <<locked>> | 86% | 34,795 psi | 56% | 2516 fps | 95.7% |
| ADI AR 2206H | <<locked>> | 80% | 44,614 psi | 72% | 2651 fps | 99.2% |
| ADI AR 2208 | <<locked>> | 80% | 37,898 psi | 61% | 2500 fps | 97.2% |
| ADI Benchmark 8208 | <<locked>> | 80% | 46,673 psi | 75% | 2657 fps | 99.9% |
| Alliant AR-Comp | <<locked>> | 80% | 46,862 psi | 76% | 2641 fps | 100% |
| Alliant Power Pro 2000-MR | 31.7 gr | 80% | 40,364 psi | 65% | 2674 fps | 97.8% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 37,550 psi | 61% | 2523 fps | 98.6% |
| Alliant Reloder-15 | <<locked>> | 80% | 40,364 psi | 65% | 2589 fps | 98% |
| Alliant Reloder-16 | <<locked>> | 86% | 35,215 psi | 57% | 2533 fps | 95.9% |
| Alliant Reloder-17 | 31.2 gr | 80% | 32,242 psi | 52% | 2484 fps | 96.6% |
| Alliant Reloder-23 | <<locked>> | 92% | 30,327 psi | 49% | 2434 fps | 95.5% |
| Alliant Reloder-26 | <<locked>> | 96% | 37,449 psi | 60% | 2674 fps | 95.9% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 43,555 psi | 70% | 2651 fps | 98.2% |
| Bofors RP3 | <<locked>> | 80% | 37,130 psi | 60% | 2526 fps | 98.6% |
| Bofors RP7 | <<locked>> | 90% | 46,122 psi | 74% | 2654 fps | 95.3% |
| Hodgdon Benchmark | <<locked>> | 80% | 48,225 psi | 78% | 2644 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 45,382 psi | 73% | 2677 fps | 99.9% |
| Hodgdon CFE223 | <<locked>> | 80% | 50,357 psi | 81% | 2825 fps | 99.6% |
| Hodgdon H380 | <<locked>> | 80% | 37,898 psi | 61% | 2526 fps | 96.1% |
| Hodgdon H414 | <<locked>> | 90% | 42,859 psi | 69% | 2680 fps | 95.2% |
| Hodgdon H4350 | <<locked>> | 92% | 49,690 psi | 80% | 2756 fps | 95.4% |
| Hodgdon H4895 | <<locked>> | 80% | 45,063 psi | 73% | 2661 fps | 99.5% |
| Hodgdon Hybrid 100V | <<locked>> | 84% | 30,153 psi | 49% | 2372 fps | 95.7% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 40,886 psi | 66% | 2631 fps | 99.3% |
| Hodgdon Superformance | 38 gr | 92% | 45,832 psi | 74% | 2759 fps | 95.3% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,295 psi | 42% | 1526 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 43,207 psi | 70% | 2612 fps | 99.3% |
| IMR 3031 | <<locked>> | 80% | 44,715 psi | 72% | 2657 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 39,740 psi | 64% | 2533 fps | 97.9% |
| IMR 4166 Enduron | <<locked>> | 82% | 44,918 psi | 72% | 2605 fps | 95.6% |
| IMR 4350 | <<locked>> | 94% | 46,122 psi | 74% | 2680 fps | 95.3% |
| IMR 4451 Enduron | <<locked>> | 88% | 45,092 psi | 73% | 2638 fps | 95.6% |
| IMR 4831 | <<locked>> | 86% | 33,794 psi | 55% | 2477 fps | 95.4% |
| IMR 4895 | <<locked>> | 80% | 41,321 psi | 67% | 2618 fps | 98.7% |
| IMR 8208 XBR | <<locked>> | 80% | 46,673 psi | 75% | 2657 fps | 99.9% |
| Lovex D073.6 | <<locked>> | 80% | 43,729 psi | 71% | 2631 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 44,701 psi | 72% | 2589 fps | 99.2% |
| Lovex S062 | <<locked>> | 80% | 39,842 psi | 64% | 2543 fps | 99.3% |
| Lovex S065 | <<locked>> | 86% | 39,247 psi | 63% | 2530 fps | 95.5% |
| Lovex S070 | <<locked>> | 90% | 42,061 psi | 68% | 2608 fps | 95.1% |
| Norma 201 | <<locked>> | 80% | 43,540 psi | 70% | 2602 fps | 99.7% |
| Norma 202 | <<locked>> | 80% | 43,961 psi | 71% | 2612 fps | 100% |
| Norma 203B | <<locked>> | 80% | 39,740 psi | 64% | 2575 fps | 98.4% |
| Norma URP | <<locked>> | 86% | 35,317 psi | 57% | 2523 fps | 95.7% |
| Ramshot Big Game | <<locked>> | 80% | 39,073 psi | 63% | 2582 fps | 98.1% |
| Ramshot Hunter | <<locked>> | 90% | 39,233 psi | 63% | 2612 fps | 95% |
| Ramshot TAC | <<locked>> | 80% | 46,485 psi | 75% | 2664 fps | 97.6% |
| Ramshot Wild Boar | <<locked>> | 80% | 45,963 psi | 74% | 2680 fps | 99.3% |
| Ramshot X-Terminator | <<locked>> | 80% | 50,328 psi | 81% | 2707 fps | 99.7% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,658 psi | 43% | 1565 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 52,359 psi | 84% | 2740 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 82% | 40,814 psi | 66% | 2562 fps | 95.2% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 42,119 psi | 68% | 2684 fps | 98.4% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 34,330 psi | 55% | 2552 fps | 99.4% |
| ReloadSwiss RS 62 | <<locked>> | 86% | 34,476 psi | 56% | 2530 fps | 95.1% |
| ReloadSwiss RS 70 | <<locked>> | 88% | 37,275 psi | 60% | 2598 fps | 95.2% |
| Rottweil R 901 | <<locked>> | 80% | 47,674 psi | 77% | 2641 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 41,524 psi | 67% | 2552 fps | 99.4% |
| Rottweil R 903 | <<locked>> | 80% | 34,795 psi | 56% | 2467 fps | 97.8% |
| Rottweil R 907 | <<locked>> | 90% | 46,122 psi | 74% | 2654 fps | 95.3% |
| Shooters World Long Rifle | <<locked>> | 86% | 39,247 psi | 63% | 2530 fps | 95.5% |
| Shooters World Match Rifle | <<locked>> | 80% | 43,729 psi | 71% | 2631 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 39,842 psi | 64% | 2543 fps | 99.3% |
| Shooters World SW4350 | <<locked>> | 90% | 42,061 psi | 68% | 2608 fps | 95.1% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 35,708 psi | 58% | 2516 fps | 97.2% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 44,643 psi | 72% | 2635 fps | 97.7% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 42,830 psi | 69% | 2615 fps | 98.9% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 45,179 psi | 73% | 2559 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 37,579 psi | 61% | 2428 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 90% | 44,164 psi | 71% | 2582 fps | 95.5% |
| Somchem S321 | <<locked>> | 80% | 50,227 psi | 81% | 2733 fps | 100% |
| Somchem S335 | <<locked>> | 80% | 44,498 psi | 72% | 2556 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 44,367 psi | 72% | 2631 fps | 99.1% |
| Somchem S355 | <<locked>> | 80% | 35,694 psi | 58% | 2474 fps | 97.8% |
| Somchem S365 | <<locked>> | 80% | 25,933 psi | 42% | 2306 fps | 95.1% |
| Vihtavuori N130 | <<locked>> | 80% | 50,923 psi | 82% | 2615 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 45,469 psi | 73% | 2552 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 41,176 psi | 66% | 2543 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 41,394 psi | 67% | 2543 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 33,866 psi | 55% | 2411 fps | 98.5% |
| Vihtavuori N160 | <<locked>> | 84% | 34,563 psi | 56% | 2470 fps | 95.3% |
| Vihtavuori N530 | <<locked>> | 80% | 46,717 psi | 75% | 2654 fps | 99.9% |
| Vihtavuori N540 | <<locked>> | 80% | 39,987 psi | 64% | 2536 fps | 100% |
| Vihtavuori N550 | <<locked>> | 86% | 36,187 psi | 58% | 2523 fps | 95.7% |
| Vihtavuori N555 | <<locked>> | 92% | 32,590 psi | 53% | 2510 fps | 95.6% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 30,081 psi | 49% | 2336 fps | 95.8% |
| Winchester 748 | <<locked>> | 80% | 46,485 psi | 75% | 2700 fps | 100% |
| Winchester 760 | <<locked>> | 90% | 42,859 psi | 69% | 2680 fps | 95.2% |
| Winchester StaBALL HD | <<locked>> | 96% | 30,472 psi | 49% | 2513 fps | 96.1% |
| Winchester StaBALL Match | <<locked>> | 80% | 42,511 psi | 69% | 2621 fps | 99.2% |
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 95 powders for 6 mm GT loaded with the .243 | 105gr | Geco SOFTPOINT. ReloadSwiss RS 70 delivers the highest muzzle velocity at 2,953 fps; across all powders the maximum-charge window runs from 1,709 fps to 2,953 fps. Alliant Reloder-16 gives the best case fill at 100 %, and 95 of the 95 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (427 MPa), the top charges use 56–90 %, leaving at least 10 % headroom. The 105.0 gr projectile in 0.243" calls for a 1:11.0 twist; slower twists will usually not stabilise this weight. Alliant Reloder-16, 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. Alliant Power Pro 2000-MR, Hodgdon Superformance, Alliant Reloder-17 rank at the top here: for 6 mm GT with the .243 | 105gr | Geco SOFTPOINT 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.