Load Specifications
Load data in caliber .338 Blaser Mag. with .338 | 220gr | Atomic 29 HP bullet and 99 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are ReloadSwiss RS 70, 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.
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You can find more information in our FAQ: How can I use the Personalized Load Calculator?
Max Load - Barrel Length: 25.6"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2015 | <<locked>> | 82% | 53,069 psi | 87% | 2618 fps | 100% |
| Accurate 2495 | <<locked>> | 88% | 55,042 psi | 90% | 2687 fps | 100% |
| Accurate 2520 | <<locked>> | 82% | 51,605 psi | 85% | 2694 fps | 100% |
| Accurate 2700 | <<locked>> | 90% | 52,011 psi | 85% | 2657 fps | 97.6% |
| Accurate 3100ᴾ | <<locked>> | 100% | 42,163 psi | 69% | 2605 fps | 97.4% |
| Accurate 4064 | <<locked>> | 90% | 55,114 psi | 90% | 2736 fps | 100% |
| Accurate 4350 | <<locked>> | 96% | 51,605 psi | 85% | 2779 fps | 99.8% |
| ADI AR 2206H | <<locked>> | 84% | 52,431 psi | 86% | 2723 fps | 100% |
| ADI AR 2208 | <<locked>> | 90% | 53,447 psi | 88% | 2726 fps | 100% |
| ADI AR 2209ᴾ | <<locked>> | 100% | 50,299 psi | 83% | 2759 fps | 96.4% |
| ADI Benchmark 8208 | <<locked>> | 84% | 54,824 psi | 90% | 2723 fps | 100% |
| Alliant AR-Comp | <<locked>> | 82% | 52,112 psi | 86% | 2644 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 86% | 51,895 psi | 85% | 2841 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 90% | 53,548 psi | 88% | 2746 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 88% | 53,998 psi | 89% | 2769 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 98% | 53,185 psi | 87% | 2838 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 94% | 54,302 psi | 89% | 2871 fps | 100% |
| Alliant Reloder-19ᴾ | <<locked>> | 100% | 49,197 psi | 81% | 2749 fps | 96.4% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 40,292 psi | 66% | 2638 fps | 99.7% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 45,324 psi | 74% | 2802 fps | 99.3% |
| Baschieri & Pellagri 107 | <<locked>> | 84% | 52,011 psi | 85% | 2740 fps | 99.9% |
| Bofors RP3 | <<locked>> | 90% | 53,751 psi | 88% | 2759 fps | 100% |
| Bofors RP7 | <<locked>> | 94% | 54,070 psi | 89% | 2740 fps | 98.2% |
| Hodgdon Benchmark | <<locked>> | 82% | 53,026 psi | 87% | 2654 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 84% | 54,172 psi | 89% | 2753 fps | 100% |
| Hodgdon H322 | <<locked>> | 82% | 54,621 psi | 90% | 2697 fps | 100% |
| Hodgdon H380 | <<locked>> | 90% | 54,940 psi | 90% | 2779 fps | 99.8% |
| Hodgdon H414 | <<locked>> | 92% | 52,663 psi | 86% | 2802 fps | 98.6% |
| Hodgdon H4350 | <<locked>> | 96% | 53,432 psi | 88% | 2766 fps | 97.5% |
| Hodgdon H4895 | <<locked>> | 84% | 52,953 psi | 87% | 2733 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 52,794 psi | 87% | 2759 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 88% | 52,576 psi | 86% | 2769 fps | 100% |
| Hodgdon Superformance | <<locked>> | 94% | 51,343 psi | 84% | 2812 fps | 98% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,607 psi | 58% | 1670 fps | 100% |
| Hodgdon VARGET | <<locked>> | 88% | 53,142 psi | 87% | 2720 fps | 100% |
| IMR 3031 | <<locked>> | 88% | 54,998 psi | 90% | 2736 fps | 100% |
| IMR 4064 | <<locked>> | 90% | 52,257 psi | 86% | 2697 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 92% | 54,752 psi | 90% | 2720 fps | 98.7% |
| IMR 4350 | <<locked>> | 98% | 54,520 psi | 90% | 2766 fps | 98.3% |
| IMR 4451 Enduron | <<locked>> | 92% | 52,692 psi | 87% | 2720 fps | 98.3% |
| IMR 4831ᴾ | <<locked>> | 100% | 49,559 psi | 81% | 2730 fps | 99.7% |
| IMR 4895 | <<locked>> | 86% | 51,880 psi | 85% | 2746 fps | 100% |
| IMR 8208 XBR | <<locked>> | 84% | 54,824 psi | 90% | 2723 fps | 100% |
| Lovex D073.6 | <<locked>> | 84% | 51,851 psi | 85% | 2697 fps | 100% |
| Lovex S060 | <<locked>> | 84% | 51,982 psi | 85% | 2654 fps | 100% |
| Lovex S062 | <<locked>> | 88% | 52,605 psi | 86% | 2700 fps | 100% |
| Lovex S065 | <<locked>> | 94% | 52,083 psi | 86% | 2713 fps | 99.2% |
| Lovex S070 | <<locked>> | 96% | 52,736 psi | 87% | 2743 fps | 98.6% |
| Norma 201 | <<locked>> | 86% | 54,418 psi | 89% | 2717 fps | 100% |
| Norma 202 | <<locked>> | 86% | 55,027 psi | 90% | 2717 fps | 100% |
| Norma 203B | <<locked>> | 88% | 53,243 psi | 87% | 2756 fps | 100% |
| Norma 204 | <<locked>> | 98% | 55,114 psi | 90% | 2815 fps | 97.3% |
| Norma MRPᴾ | <<locked>> | 100% | 45,223 psi | 74% | 2759 fps | 97.1% |
| Norma URP | <<locked>> | 98% | 54,447 psi | 89% | 2818 fps | 99.9% |
| Ramshot Big Game | <<locked>> | 88% | 53,824 psi | 88% | 2782 fps | 100% |
| Ramshot Hunter | <<locked>> | 98% | 53,229 psi | 87% | 2818 fps | 99.2% |
| Ramshot TAC | <<locked>> | 84% | 54,998 psi | 90% | 2746 fps | 99.6% |
| Ramshot Wild Boar | <<locked>> | 84% | 54,737 psi | 90% | 2762 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 35,940 psi | 59% | 1709 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 88% | 51,764 psi | 85% | 2710 fps | 98.7% |
| ReloadSwiss RS 52 | <<locked>> | 86% | 54,636 psi | 90% | 2835 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 92% | 54,128 psi | 89% | 2867 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 96% | 51,517 psi | 85% | 2802 fps | 99.7% |
| ReloadSwiss RS 70 | <<locked>> | 98% | 54,621 psi | 90% | 2887 fps | 99.9% |
| Rottweil R 901 | <<locked>> | 84% | 55,114 psi | 90% | 2694 fps | 100% |
| Rottweil R 902 | <<locked>> | 88% | 54,911 psi | 90% | 2717 fps | 100% |
| Rottweil R 903 | <<locked>> | 92% | 53,853 psi | 88% | 2753 fps | 100% |
| Rottweil R 905ᴾ | <<locked>> | 100% | 47,979 psi | 79% | 2730 fps | 96.3% |
| Rottweil R 907 | <<locked>> | 94% | 54,070 psi | 89% | 2740 fps | 98.2% |
| Shooters World Long Rifle | <<locked>> | 94% | 52,083 psi | 86% | 2713 fps | 99.2% |
| Shooters World Match Rifle | <<locked>> | 84% | 51,851 psi | 85% | 2697 fps | 100% |
| Shooters World Precision | <<locked>> | 88% | 52,605 psi | 86% | 2700 fps | 100% |
| Shooters World SW4350 | <<locked>> | 96% | 52,736 psi | 87% | 2743 fps | 98.6% |
| SNPE Vectan SP 11 | <<locked>> | 90% | 52,243 psi | 86% | 2766 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 84% | 53,229 psi | 87% | 2723 fps | 99.7% |
| SNPE Vectan SP 9 | <<locked>> | 86% | 54,259 psi | 89% | 2746 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 84% | 52,460 psi | 86% | 2608 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 90% | 52,953 psi | 87% | 2612 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 94% | 52,025 psi | 85% | 2664 fps | 98.3% |
| SNPE Vectan Tubal 8000ᴾ | <<locked>> | 100% | 47,514 psi | 78% | 2723 fps | 96.2% |
| Somchem S335 | <<locked>> | 84% | 51,880 psi | 85% | 2605 fps | 100% |
| Somchem S341 | <<locked>> | 84% | 52,953 psi | 87% | 2713 fps | 100% |
| Somchem S355 | <<locked>> | 92% | 54,070 psi | 89% | 2749 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 52,417 psi | 86% | 2818 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 48,544 psi | 80% | 2710 fps | 97.2% |
| Unknown powder | <<locked>> | 94% | 52,112 psi | 86% | 2776 fps | 99.6% |
| Vihtavuori N133 | <<locked>> | 84% | 52,881 psi | 87% | 2592 fps | 100% |
| Vihtavuori N135 | <<locked>> | 88% | 54,795 psi | 90% | 2674 fps | 100% |
| Vihtavuori N140 | <<locked>> | 86% | 52,112 psi | 86% | 2648 fps | 100% |
| Vihtavuori N150 | <<locked>> | 92% | 52,228 psi | 86% | 2684 fps | 100% |
| Vihtavuori N160 | <<locked>> | 96% | 53,388 psi | 88% | 2766 fps | 99.9% |
| Vihtavuori N530 | <<locked>> | 84% | 55,100 psi | 90% | 2720 fps | 100% |
| Vihtavuori N540 | <<locked>> | 88% | 53,751 psi | 88% | 2694 fps | 100% |
| Vihtavuori N550 | <<locked>> | 96% | 52,330 psi | 86% | 2769 fps | 99.7% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 44,512 psi | 73% | 2710 fps | 99.6% |
| Winchester 6.5 StaBALL | <<locked>> | 96% | 53,432 psi | 88% | 2743 fps | 100% |
| Winchester 760 | <<locked>> | 92% | 52,663 psi | 86% | 2802 fps | 98.6% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 35,998 psi | 59% | 2654 fps | 99.8% |
| Winchester Supreme 780ᴾ | <<locked>> | 100% | 50,894 psi | 84% | 2733 fps | 96.5% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 25.6"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2015 | <<locked>> | 80% | 49,850 psi | 82% | 2575 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 42,192 psi | 69% | 2503 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 48,225 psi | 79% | 2641 fps | 100% |
| Accurate 2700 | <<locked>> | 84% | 42,598 psi | 70% | 2500 fps | 95.4% |
| Accurate 3100 | <<locked>> | 94% | 34,272 psi | 56% | 2448 fps | 95% |
| Accurate 4064 | <<locked>> | 80% | 39,958 psi | 66% | 2503 fps | 100% |
| Accurate 4350 | <<locked>> | 82% | 31,459 psi | 52% | 2392 fps | 95.9% |
| ADI AR 2206H | <<locked>> | 80% | 45,948 psi | 75% | 2621 fps | 99.8% |
| ADI AR 2208 | <<locked>> | 80% | 39,088 psi | 64% | 2477 fps | 98.6% |
| ADI AR 2209 | <<locked>> | 98% | 47,195 psi | 77% | 2703 fps | 95.6% |
| ADI Benchmark 8208 | <<locked>> | 80% | 48,109 psi | 79% | 2625 fps | 100% |
| Alliant AR-Comp | <<locked>> | 80% | 48,762 psi | 80% | 2598 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 41,959 psi | 69% | 2661 fps | 99.1% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 38,812 psi | 64% | 2500 fps | 99.5% |
| Alliant Reloder-15 | <<locked>> | 80% | 41,597 psi | 68% | 2559 fps | 99.1% |
| Alliant Reloder-16 | <<locked>> | 80% | 30,023 psi | 49% | 2356 fps | 95.2% |
| Alliant Reloder-17 | 61.2 gr | 80% | 33,489 psi | 55% | 2480 fps | 98.4% |
| Alliant Reloder-19 | <<locked>> | 98% | 46,253 psi | 76% | 2697 fps | 95.6% |
| Alliant Reloder-23 | <<locked>> | 88% | 27,630 psi | 45% | 2323 fps | 95.8% |
| Alliant Reloder-26 | <<locked>> | 90% | 31,734 psi | 52% | 2493 fps | 95.1% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 45,455 psi | 75% | 2631 fps | 99.3% |
| Bofors RP3 | <<locked>> | 80% | 38,421 psi | 63% | 2503 fps | 99.5% |
| Bofors RP7 | <<locked>> | 86% | 42,047 psi | 69% | 2533 fps | 95.6% |
| Hodgdon Benchmark | <<locked>> | 80% | 49,951 psi | 82% | 2612 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 47,065 psi | 77% | 2648 fps | 100% |
| Hodgdon H322 | <<locked>> | 80% | 51,242 psi | 84% | 2651 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 39,233 psi | 64% | 2510 fps | 97.7% |
| Hodgdon H414 | <<locked>> | 84% | 39,813 psi | 65% | 2575 fps | 95.7% |
| Hodgdon H4350 | <<locked>> | 90% | 44,251 psi | 73% | 2612 fps | 95.4% |
| Hodgdon H4895 | <<locked>> | 80% | 46,427 psi | 76% | 2631 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 27,383 psi | 45% | 2260 fps | 96% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 40,074 psi | 66% | 2562 fps | 99.7% |
| Hodgdon Superformance | 71.2 gr | 88% | 41,423 psi | 68% | 2631 fps | 95.6% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,513 psi | 44% | 1493 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 41,278 psi | 68% | 2523 fps | 99.6% |
| IMR 3031 | <<locked>> | 80% | 42,453 psi | 70% | 2556 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 38,334 psi | 63% | 2457 fps | 98.6% |
| IMR 4166 Enduron | <<locked>> | 80% | 38,174 psi | 63% | 2425 fps | 95% |
| IMR 4350 | <<locked>> | 90% | 42,322 psi | 69% | 2562 fps | 95.7% |
| IMR 4451 Enduron | <<locked>> | 82% | 38,609 psi | 63% | 2464 fps | 95% |
| IMR 4831 | <<locked>> | 84% | 29,689 psi | 49% | 2333 fps | 95.2% |
| IMR 4895 | <<locked>> | 80% | 42,641 psi | 70% | 2589 fps | 99.6% |
| IMR 8208 XBR | <<locked>> | 80% | 48,109 psi | 79% | 2625 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 45,223 psi | 74% | 2598 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 46,050 psi | 76% | 2559 fps | 99.8% |
| Lovex S062 | <<locked>> | 80% | 41,031 psi | 67% | 2513 fps | 99.9% |
| Lovex S065 | <<locked>> | 80% | 33,547 psi | 55% | 2359 fps | 95% |
| Lovex S070 | <<locked>> | 86% | 38,406 psi | 63% | 2487 fps | 95.4% |
| Norma 201 | <<locked>> | 80% | 44,976 psi | 74% | 2572 fps | 100% |
| Norma 202 | <<locked>> | 80% | 45,440 psi | 75% | 2575 fps | 100% |
| Norma 203B | <<locked>> | 80% | 40,944 psi | 67% | 2549 fps | 99.4% |
| Norma 204 | <<locked>> | 92% | 44,933 psi | 74% | 2648 fps | 95% |
| Norma MRP | <<locked>> | 96% | 39,508 psi | 65% | 2641 fps | 95.3% |
| Norma URP | <<locked>> | 80% | 29,936 psi | 49% | 2346 fps | 95% |
| Ramshot Big Game | <<locked>> | 80% | 40,669 psi | 67% | 2566 fps | 99.2% |
| Ramshot Hunter | <<locked>> | 86% | 35,781 psi | 59% | 2493 fps | 95.3% |
| Ramshot TAC | <<locked>> | 80% | 48,080 psi | 79% | 2641 fps | 98.8% |
| Ramshot Wild Boar | <<locked>> | 80% | 47,674 psi | 78% | 2657 fps | 99.9% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,716 psi | 44% | 1526 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 39,697 psi | 65% | 2493 fps | 96.2% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 44,135 psi | 72% | 2664 fps | 99.5% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 35,694 psi | 59% | 2543 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 82% | 31,401 psi | 52% | 2411 fps | 95.4% |
| ReloadSwiss RS 70 | 65.3 gr | 84% | 33,779 psi | 55% | 2477 fps | 95.5% |
| Rottweil R 901 | <<locked>> | 80% | 48,762 psi | 80% | 2602 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 42,627 psi | 70% | 2523 fps | 99.9% |
| Rottweil R 903 | <<locked>> | 80% | 36,056 psi | 59% | 2448 fps | 99% |
| Rottweil R 905 | <<locked>> | 98% | 44,715 psi | 73% | 2671 fps | 95.5% |
| Rottweil R 907 | <<locked>> | 86% | 42,047 psi | 69% | 2533 fps | 95.6% |
| Shooters World Long Rifle | <<locked>> | 80% | 33,547 psi | 55% | 2359 fps | 95% |
| Shooters World Match Rifle | <<locked>> | 80% | 45,223 psi | 74% | 2598 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 41,031 psi | 67% | 2513 fps | 99.9% |
| Shooters World SW4350 | <<locked>> | 86% | 38,406 psi | 63% | 2487 fps | 95.4% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 37,159 psi | 61% | 2500 fps | 98.7% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 46,398 psi | 76% | 2615 fps | 99% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 44,454 psi | 73% | 2592 fps | 99.7% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 46,427 psi | 76% | 2520 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 38,667 psi | 63% | 2395 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 86% | 40,045 psi | 66% | 2461 fps | 95.7% |
| SNPE Vectan Tubal 8000 | <<locked>> | 98% | 44,309 psi | 73% | 2667 fps | 95.3% |
| Somchem S335 | <<locked>> | 80% | 45,934 psi | 75% | 2520 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 46,267 psi | 76% | 2612 fps | 99.8% |
| Somchem S355 | <<locked>> | 80% | 36,985 psi | 61% | 2457 fps | 99% |
| Somchem S365 | <<locked>> | 80% | 26,687 psi | 44% | 2297 fps | 97.2% |
| Somchem S385 | <<locked>> | 96% | 42,540 psi | 70% | 2605 fps | 95.8% |
| Unknown powder | <<locked>> | 80% | 32,532 psi | 53% | 2398 fps | 95.3% |
| Vihtavuori N133 | <<locked>> | 80% | 46,862 psi | 77% | 2510 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 42,525 psi | 70% | 2500 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 43,018 psi | 71% | 2513 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 35,128 psi | 58% | 2395 fps | 99.5% |
| Vihtavuori N160 | <<locked>> | 80% | 31,212 psi | 51% | 2346 fps | 95.5% |
| Vihtavuori N530 | <<locked>> | 80% | 48,370 psi | 79% | 2621 fps | 100% |
| Vihtavuori N540 | <<locked>> | 80% | 41,394 psi | 68% | 2507 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 30,719 psi | 50% | 2349 fps | 95% |
| Vihtavuori N555 | <<locked>> | 88% | 29,631 psi | 49% | 2392 fps | 95.9% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 31,096 psi | 51% | 2326 fps | 97.7% |
| Winchester 760 | <<locked>> | 84% | 39,813 psi | 65% | 2575 fps | 95.7% |
| Winchester StaBALL HD | <<locked>> | 90% | 25,904 psi | 43% | 2336 fps | 95.1% |
| Winchester Supreme 780 | <<locked>> | 98% | 47,413 psi | 78% | 2677 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 114 powders for .338 Blaser Mag. loaded with the .338 | 220gr | Atomic 29 HP. ReloadSwiss RS 70 delivers the highest muzzle velocity at 2,887 fps; across all powders the maximum-charge window runs from 1,670 fps to 2,887 fps. Accurate 3100 gives the best case fill at 100 %, and 114 of the 114 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (420 MPa), the top charges use 57–90 %, leaving at least 10 % headroom. The 220.0 gr projectile in 0.338" calls for a 1:14.0 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. ReloadSwiss RS 70, Hodgdon Superformance, Alliant Reloder-17 rank at the top here: for .338 Blaser Mag. with the .338 | 220gr | Atomic 29 HP they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, ADI AR 2213, Alliant Reloder-22, Bofors RP15 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.