Load Specifications
Bullet Manufacturer:Swift
Bullet Weight:210 gr
Bullet Diameter:0.338"
Bullet Length:<<locked>>
Caliber:.338 Weatherby RPM load data
Case Length (l3):2.55"
Cartridge Length (C.O.L.):<<locked>>
Case Capacity:81.6 Grains of Water
Primer Size:Large Rifle Magnum (LRM)
Barrel Length:24"
Max. allowed Pressure:65,000 psi
Recommended Twist Rate:1:13.5
Load data in caliber .338 Weatherby RPM with .338 | 210gr | Swift Scirocco bullet and 105 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, ReloadSwiss RS 52 and Hodgdon LEVERevolution.
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>> | 90% | 58,305 psi | 90% | 2644 fps | 100% |
| Accurate 2200 | <<locked>> | 82% | 58,320 psi | 90% | 2746 fps | 99.5% |
| Accurate 2460 | <<locked>> | 86% | 56,811 psi | 87% | 2674 fps | 100% |
| Accurate 2495 | <<locked>> | 94% | 55,912 psi | 86% | 2664 fps | 100% |
| Accurate 2520 | <<locked>> | 90% | 58,610 psi | 90% | 2733 fps | 100% |
| Accurate 2700 | <<locked>> | 94% | 56,391 psi | 87% | 2654 fps | 95.9% |
| Accurate 4064 | <<locked>> | 96% | 55,506 psi | 85% | 2703 fps | 100% |
| Accurate 4350ᴾ | <<locked>> | 100% | 47,485 psi | 73% | 2661 fps | 98% |
| Accurate LT-30 | <<locked>> | 84% | 57,667 psi | 89% | 2592 fps | 100% |
| Accurate LT-32 | <<locked>> | 84% | 58,088 psi | 89% | 2615 fps | 100% |
| ADI AR 2206H | <<locked>> | 92% | 57,217 psi | 88% | 2740 fps | 99.8% |
| ADI AR 2208 | <<locked>> | 98% | 57,957 psi | 89% | 2730 fps | 99.6% |
| ADI AR 2219 | <<locked>> | 82% | 55,100 psi | 85% | 2664 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 90% | 56,376 psi | 87% | 2694 fps | 100% |
| Alliant AR-Comp | <<locked>> | 90% | 56,521 psi | 87% | 2674 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 86% | 58,204 psi | 90% | 2795 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 94% | 56,797 psi | 87% | 2848 fps | 99.6% |
| Alliant Reloder- TS 15.5 | <<locked>> | 98% | 57,290 psi | 88% | 2749 fps | 100% |
| Alliant Reloder-10x | <<locked>> | 86% | 58,102 psi | 89% | 2651 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 96% | 58,450 psi | 90% | 2776 fps | 99.7% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 47,195 psi | 73% | 2671 fps | 98.1% |
| Alliant Reloder-17ᴾ | <<locked>> | 100% | 54,607 psi | 84% | 2818 fps | 99.9% |
| Baschieri & Pellagri 106 | <<locked>> | 84% | 56,927 psi | 88% | 2592 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 92% | 57,116 psi | 88% | 2756 fps | 99.3% |
| Bofors RP3 | <<locked>> | 98% | 58,088 psi | 89% | 2769 fps | 100% |
| Bofors RP7ᴾ | <<locked>> | 100% | 55,056 psi | 85% | 2680 fps | 96% |
| Hodgdon Benchmark | <<locked>> | 90% | 58,639 psi | 90% | 2680 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 90% | 55,317 psi | 85% | 2726 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 88% | 57,479 psi | 88% | 2818 fps | 99.7% |
| Hodgdon H322 | <<locked>> | 86% | 57,392 psi | 88% | 2694 fps | 100% |
| Hodgdon H335 | <<locked>> | 86% | 58,465 psi | 90% | 2720 fps | 100% |
| Hodgdon H380 | <<locked>> | 96% | 55,883 psi | 86% | 2730 fps | 98.8% |
| Hodgdon H414ᴾ | <<locked>> | 100% | 50,966 psi | 78% | 2710 fps | 96% |
| Hodgdon H4895 | <<locked>> | 92% | 57,798 psi | 89% | 2749 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 43,352 psi | 67% | 2559 fps | 98.6% |
| Hodgdon LEVERevolution | <<locked>> | 94% | 56,637 psi | 87% | 2779 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 34,867 psi | 54% | 1608 fps | 100% |
| Hodgdon VARGET | <<locked>> | 92% | 55,651 psi | 86% | 2703 fps | 99.9% |
| IMR 3031 | <<locked>> | 92% | 56,971 psi | 88% | 2730 fps | 100% |
| IMR 4064 | <<locked>> | 96% | 57,493 psi | 88% | 2717 fps | 99.6% |
| IMR 4166 Enduron | <<locked>> | 94% | 58,349 psi | 90% | 2700 fps | 97.2% |
| IMR 4198 | <<locked>> | 86% | 58,334 psi | 90% | 2612 fps | 100% |
| IMR 4451 Enduronᴾ | <<locked>> | 100% | 57,145 psi | 88% | 2713 fps | 96.9% |
| IMR 4831ᴾ | <<locked>> | 100% | 45,368 psi | 70% | 2608 fps | 97.7% |
| IMR 4895 | <<locked>> | 94% | 56,115 psi | 86% | 2756 fps | 99.8% |
| IMR 8208 XBR | <<locked>> | 90% | 56,376 psi | 87% | 2694 fps | 100% |
| Lovex D073.5 | <<locked>> | 86% | 56,985 psi | 88% | 2687 fps | 100% |
| Lovex D073.6 | <<locked>> | 92% | 56,362 psi | 87% | 2717 fps | 100% |
| Lovex S060 | <<locked>> | 92% | 57,217 psi | 88% | 2667 fps | 99.8% |
| Lovex S062 | <<locked>> | 96% | 57,174 psi | 88% | 2717 fps | 100% |
| Lovex S065ᴾ | <<locked>> | 100% | 52,591 psi | 81% | 2654 fps | 97.5% |
| Lovex S070ᴾ | <<locked>> | 100% | 49,951 psi | 77% | 2635 fps | 95.9% |
| Norma 200 | <<locked>> | 82% | 57,957 psi | 89% | 2621 fps | 100% |
| Norma 201 | <<locked>> | 92% | 55,767 psi | 86% | 2687 fps | 100% |
| Norma 202 | <<locked>> | 92% | 56,188 psi | 86% | 2690 fps | 100% |
| Norma 203B | <<locked>> | 96% | 57,493 psi | 88% | 2762 fps | 99.8% |
| Norma URPᴾ | <<locked>> | 100% | 47,326 psi | 73% | 2654 fps | 97.9% |
| Ramshot Big Game | <<locked>> | 96% | 58,117 psi | 89% | 2789 fps | 99.8% |
| Ramshot Hunterᴾ | <<locked>> | 100% | 46,615 psi | 72% | 2644 fps | 95.8% |
| Ramshot TAC | <<locked>> | 90% | 56,956 psi | 88% | 2710 fps | 98.4% |
| Ramshot Wild Boar | <<locked>> | 90% | 56,246 psi | 87% | 2730 fps | 99.7% |
| Ramshot X-Terminator | <<locked>> | 88% | 57,899 psi | 89% | 2700 fps | 99.8% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 35,186 psi | 54% | 1647 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 86% | 56,231 psi | 87% | 2680 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 96% | 56,536 psi | 87% | 2713 fps | 97.5% |
| ReloadSwiss RS 52 | <<locked>> | 92% | 54,926 psi | 85% | 2789 fps | 99.5% |
| ReloadSwiss RS 60ᴾ | <<locked>> | 100% | 58,291 psi | 90% | 2874 fps | 100% |
| ReloadSwiss RS 62ᴾ | <<locked>> | 100% | 47,224 psi | 73% | 2680 fps | 97.7% |
| ReloadSwiss RS 70ᴾ | <<locked>> | 100% | 48,283 psi | 74% | 2700 fps | 97.1% |
| Rottweil R 901 | <<locked>> | 90% | 56,927 psi | 88% | 2671 fps | 100% |
| Rottweil R 902 | <<locked>> | 94% | 56,202 psi | 86% | 2680 fps | 100% |
| Rottweil R 903ᴾ | <<locked>> | 100% | 57,682 psi | 89% | 2756 fps | 100% |
| Rottweil R 907ᴾ | <<locked>> | 100% | 55,056 psi | 85% | 2680 fps | 96% |
| Shooters World Long Rifleᴾ | <<locked>> | 100% | 52,591 psi | 81% | 2654 fps | 97.5% |
| Shooters World Match Rifle | <<locked>> | 92% | 56,362 psi | 87% | 2717 fps | 100% |
| Shooters World Precision | <<locked>> | 96% | 57,174 psi | 88% | 2717 fps | 100% |
| Shooters World SW4350ᴾ | <<locked>> | 100% | 49,951 psi | 77% | 2635 fps | 95.9% |
| Shooters World Tactical Rifle | <<locked>> | 84% | 56,072 psi | 86% | 2654 fps | 99.9% |
| SNPE Vectan BA6 1/2 | <<locked>> | 82% | 57,711 psi | 89% | 2346 fps | 100% |
| SNPE Vectan SP 10 | <<locked>> | 82% | 55,259 psi | 85% | 2674 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 98% | 55,854 psi | 86% | 2766 fps | 99.7% |
| SNPE Vectan SP 3 | <<locked>> | 84% | 55,593 psi | 86% | 2628 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 90% | 55,027 psi | 85% | 2687 fps | 98.5% |
| SNPE Vectan SP 9 | <<locked>> | 92% | 55,637 psi | 86% | 2713 fps | 99.7% |
| SNPE Vectan Tubal 3000 | <<locked>> | 92% | 58,218 psi | 90% | 2635 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 98% | 57,624 psi | 89% | 2625 fps | 100% |
| SNPE Vectan Tubal 7000ᴾ | <<locked>> | 100% | 53,156 psi | 82% | 2612 fps | 96.2% |
| Somchem S321 | <<locked>> | 88% | 57,957 psi | 89% | 2733 fps | 100% |
| Somchem S335 | <<locked>> | 92% | 56,913 psi | 88% | 2628 fps | 100% |
| Somchem S341 | <<locked>> | 92% | 58,465 psi | 90% | 2733 fps | 99.8% |
| Somchem S355ᴾ | <<locked>> | 100% | 58,044 psi | 89% | 2753 fps | 99.9% |
| Somchem S365ᴾ | <<locked>> | 100% | 42,308 psi | 65% | 2608 fps | 99.5% |
| Vihtavuori N130 | <<locked>> | 88% | 57,870 psi | 89% | 2602 fps | 100% |
| Vihtavuori N133 | <<locked>> | 92% | 58,102 psi | 89% | 2618 fps | 100% |
| Vihtavuori N135 | <<locked>> | 94% | 55,332 psi | 85% | 2651 fps | 100% |
| Vihtavuori N140 | <<locked>> | 94% | 56,811 psi | 87% | 2671 fps | 100% |
| Vihtavuori N150ᴾ | <<locked>> | 100% | 56,275 psi | 87% | 2690 fps | 100% |
| Vihtavuori N160ᴾ | <<locked>> | 100% | 49,951 psi | 77% | 2657 fps | 98.2% |
| Vihtavuori N530 | <<locked>> | 90% | 57,014 psi | 88% | 2694 fps | 100% |
| Vihtavuori N540 | <<locked>> | 96% | 58,508 psi | 90% | 2713 fps | 100% |
| Vihtavuori N550ᴾ | <<locked>> | 100% | 49,008 psi | 75% | 2661 fps | 97.9% |
| Winchester 6.5 StaBALLᴾ | <<locked>> | 100% | 51,068 psi | 79% | 2644 fps | 99.7% |
| Winchester 748 | <<locked>> | 90% | 56,550 psi | 87% | 2743 fps | 100% |
| Winchester 760ᴾ | <<locked>> | 100% | 51,227 psi | 79% | 2713 fps | 96% |
| Winchester StaBALL Match | <<locked>> | 92% | 55,201 psi | 85% | 2720 fps | 99.9% |
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% | 42,888 psi | 66% | 2431 fps | 100% |
| Accurate 2200 | <<locked>> | 80% | 54,534 psi | 84% | 2690 fps | 99.2% |
| Accurate 2460 | <<locked>> | 80% | 46,615 psi | 72% | 2533 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 35,389 psi | 54% | 2352 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 41,742 psi | 64% | 2487 fps | 99.8% |
| Accurate 2700 | <<locked>> | 92% | 52,881 psi | 81% | 2605 fps | 95.2% |
| Accurate 4064 | <<locked>> | 80% | 33,446 psi | 51% | 2336 fps | 99.3% |
| Accurate 4350 | <<locked>> | 94% | 38,479 psi | 59% | 2500 fps | 95.8% |
| Accurate LT-30 | <<locked>> | 80% | 51,111 psi | 79% | 2507 fps | 100% |
| Accurate LT-32 | <<locked>> | 80% | 51,503 psi | 79% | 2530 fps | 100% |
| ADI AR 2206H | <<locked>> | 80% | 39,407 psi | 61% | 2444 fps | 97.3% |
| ADI AR 2208 | <<locked>> | 82% | 35,636 psi | 55% | 2346 fps | 95.4% |
| ADI AR 2219 | <<locked>> | 80% | 51,503 psi | 79% | 2618 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 80% | 41,394 psi | 64% | 2454 fps | 98.8% |
| Alliant AR-Comp | <<locked>> | 80% | 40,495 psi | 62% | 2454 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 80% | 47,993 psi | 74% | 2641 fps | 99.4% |
| Alliant Power Pro 2000-MR | 54.7 gr | 82% | 37,927 psi | 58% | 2503 fps | 95.7% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 32,735 psi | 50% | 2320 fps | 96.3% |
| Alliant Reloder-10x | <<locked>> | 80% | 48,283 psi | 74% | 2520 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 35,259 psi | 54% | 2375 fps | 95.5% |
| Alliant Reloder-16 | <<locked>> | 92% | 37,014 psi | 57% | 2461 fps | 95.1% |
| Alliant Reloder-17 | <<locked>> | 84% | 32,097 psi | 49% | 2372 fps | 95% |
| Baschieri & Pellagri 106 | <<locked>> | 80% | 50,198 psi | 77% | 2507 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 38,218 psi | 59% | 2438 fps | 95.8% |
| Bofors RP3 | <<locked>> | 80% | 31,937 psi | 49% | 2313 fps | 96.2% |
| Bofors RP7 | <<locked>> | 98% | 51,822 psi | 80% | 2631 fps | 95.3% |
| Hodgdon Benchmark | <<locked>> | 80% | 43,337 psi | 67% | 2451 fps | 99.4% |
| Hodgdon BL-C2 | <<locked>> | 80% | 39,450 psi | 61% | 2467 fps | 98.9% |
| Hodgdon CFE223 | <<locked>> | 80% | 43,366 psi | 67% | 2595 fps | 97.8% |
| Hodgdon H322 | <<locked>> | 80% | 47,108 psi | 72% | 2552 fps | 100% |
| Hodgdon H335 | <<locked>> | 80% | 47,877 psi | 74% | 2575 fps | 100% |
| Hodgdon H380 | <<locked>> | 86% | 40,277 psi | 62% | 2470 fps | 95.6% |
| Hodgdon H414 | <<locked>> | 98% | 47,732 psi | 73% | 2654 fps | 95.2% |
| Hodgdon H4895 | <<locked>> | 80% | 39,668 psi | 61% | 2454 fps | 97.9% |
| Hodgdon Hybrid 100V | <<locked>> | 90% | 31,720 psi | 49% | 2313 fps | 95.1% |
| Hodgdon LEVERevolution | 52.3 gr | 80% | 35,462 psi | 55% | 2418 fps | 97.3% |
| Hodgdon TrailBoss | <<locked>> | 80% | 25,947 psi | 40% | 1437 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 38,145 psi | 59% | 2408 fps | 97.5% |
| IMR 3031 | <<locked>> | 80% | 38,711 psi | 60% | 2457 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 35,143 psi | 54% | 2329 fps | 95.5% |
| IMR 4166 Enduron | <<locked>> | 88% | 48,414 psi | 74% | 2549 fps | 95.2% |
| IMR 4198 | <<locked>> | 80% | 48,907 psi | 75% | 2487 fps | 100% |
| IMR 4451 Enduron | <<locked>> | 96% | 50,792 psi | 78% | 2618 fps | 95.6% |
| IMR 4831 | <<locked>> | 94% | 37,405 psi | 58% | 2461 fps | 95.5% |
| IMR 4895 | <<locked>> | 80% | 36,085 psi | 56% | 2405 fps | 96.5% |
| IMR 8208 XBR | <<locked>> | 80% | 41,394 psi | 64% | 2454 fps | 98.8% |
| Lovex D073.5 | <<locked>> | 80% | 46,296 psi | 71% | 2536 fps | 99.8% |
| Lovex D073.6 | <<locked>> | 80% | 37,826 psi | 58% | 2425 fps | 99.3% |
| Lovex S060 | <<locked>> | 80% | 39,958 psi | 61% | 2388 fps | 97.5% |
| Lovex S062 | <<locked>> | 80% | 34,853 psi | 54% | 2336 fps | 97.4% |
| Lovex S065 | <<locked>> | 94% | 43,961 psi | 68% | 2513 fps | 95.7% |
| Lovex S070 | <<locked>> | 98% | 47,079 psi | 72% | 2585 fps | 95.2% |
| Norma 200 | <<locked>> | 80% | 54,534 psi | 84% | 2582 fps | 100% |
| Norma 201 | <<locked>> | 80% | 38,624 psi | 59% | 2402 fps | 98.4% |
| Norma 202 | <<locked>> | 80% | 38,754 psi | 60% | 2418 fps | 99.7% |
| Norma 203B | <<locked>> | 80% | 34,650 psi | 53% | 2365 fps | 96% |
| Norma URP | <<locked>> | 92% | 36,796 psi | 57% | 2454 fps | 95% |
| Ramshot Big Game | <<locked>> | 80% | 33,968 psi | 52% | 2369 fps | 95.3% |
| Ramshot Hunter | <<locked>> | 98% | 43,700 psi | 67% | 2589 fps | 95% |
| Ramshot TAC | <<locked>> | 80% | 41,249 psi | 63% | 2451 fps | 95.1% |
| Ramshot Wild Boar | <<locked>> | 80% | 40,321 psi | 62% | 2470 fps | 97.5% |
| Ramshot X-Terminator | <<locked>> | 80% | 44,628 psi | 69% | 2497 fps | 98.3% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,121 psi | 40% | 1470 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 46,499 psi | 72% | 2539 fps | 99.9% |
| ReloadSwiss RS 50 | <<locked>> | 90% | 46,601 psi | 72% | 2559 fps | 95.5% |
| ReloadSwiss RS 52 | 51.7 gr | 80% | 36,289 psi | 56% | 2461 fps | 95.8% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 30,066 psi | 46% | 2329 fps | 96.8% |
| ReloadSwiss RS 62 | <<locked>> | 94% | 38,609 psi | 59% | 2520 fps | 95.3% |
| ReloadSwiss RS 70 | <<locked>> | 96% | 42,163 psi | 65% | 2582 fps | 95.3% |
| Rottweil R 901 | <<locked>> | 80% | 42,453 psi | 65% | 2451 fps | 99.9% |
| Rottweil R 902 | <<locked>> | 80% | 36,796 psi | 57% | 2359 fps | 97.9% |
| Rottweil R 903 | <<locked>> | 80% | 30,037 psi | 46% | 2260 fps | 95% |
| Rottweil R 907 | <<locked>> | 98% | 51,822 psi | 80% | 2631 fps | 95.3% |
| Shooters World Long Rifle | <<locked>> | 94% | 43,961 psi | 68% | 2513 fps | 95.7% |
| Shooters World Match Rifle | <<locked>> | 80% | 37,826 psi | 58% | 2425 fps | 99.3% |
| Shooters World Precision | <<locked>> | 80% | 34,853 psi | 54% | 2336 fps | 97.4% |
| Shooters World SW4350 | <<locked>> | 98% | 47,079 psi | 72% | 2585 fps | 95.2% |
| Shooters World Tactical Rifle | <<locked>> | 80% | 48,907 psi | 75% | 2549 fps | 99.5% |
| SNPE Vectan BA6 1/2 | <<locked>> | 80% | 54,926 psi | 85% | 2313 fps | 100% |
| SNPE Vectan SP 10 | <<locked>> | 80% | 51,880 psi | 80% | 2628 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 82% | 33,330 psi | 51% | 2359 fps | 95.2% |
| SNPE Vectan SP 3 | <<locked>> | 80% | 49,269 psi | 76% | 2543 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 39,146 psi | 60% | 2421 fps | 95.1% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 37,855 psi | 58% | 2411 fps | 96.9% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 40,321 psi | 62% | 2372 fps | 99.8% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 33,185 psi | 51% | 2244 fps | 99.5% |
| SNPE Vectan Tubal 7000 | <<locked>> | 98% | 49,806 psi | 77% | 2562 fps | 95.5% |
| Somchem S321 | <<locked>> | 80% | 44,396 psi | 68% | 2530 fps | 99.4% |
| Somchem S335 | <<locked>> | 80% | 39,711 psi | 61% | 2372 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 38,943 psi | 60% | 2425 fps | 97.1% |
| Somchem S355 | <<locked>> | 80% | 31,227 psi | 48% | 2274 fps | 95.2% |
| Somchem S365 | <<locked>> | 88% | 28,935 psi | 45% | 2300 fps | 95.4% |
| Vihtavuori N130 | <<locked>> | 80% | 45,658 psi | 70% | 2438 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 40,466 psi | 62% | 2372 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 35,795 psi | 55% | 2352 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 36,492 psi | 56% | 2352 fps | 99.7% |
| Vihtavuori N150 | <<locked>> | 80% | 29,486 psi | 45% | 2215 fps | 96.1% |
| Vihtavuori N160 | <<locked>> | 92% | 38,595 psi | 59% | 2454 fps | 95.5% |
| Vihtavuori N530 | <<locked>> | 80% | 41,220 psi | 63% | 2451 fps | 98.8% |
| Vihtavuori N540 | <<locked>> | 80% | 35,186 psi | 54% | 2343 fps | 99.2% |
| Vihtavuori N550 | <<locked>> | 92% | 37,637 psi | 58% | 2454 fps | 95% |
| Winchester 6.5 StaBALL | <<locked>> | 86% | 32,169 psi | 49% | 2287 fps | 95.3% |
| Winchester 748 | <<locked>> | 80% | 40,277 psi | 62% | 2487 fps | 99.3% |
| Winchester 760 | <<locked>> | 98% | 47,979 psi | 74% | 2661 fps | 95.2% |
| Winchester StaBALL Match | <<locked>> | 80% | 37,014 psi | 57% | 2411 fps | 97.3% |
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 105 powders for .338 Weatherby RPM loaded with the .338 | 210gr | Swift Scirocco. ReloadSwiss RS 60 delivers the highest muzzle velocity at 2,874 fps; across all powders the maximum-charge window runs from 1,608 fps to 2,874 fps. Accurate 4350 gives the best case fill at 100 %, and 105 of the 105 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (448 MPa), the top charges use 54–90 %, leaving at least 10 % headroom. The 210.0 gr projectile in 0.338" calls for a 1:13.5 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. Alliant Power Pro 2000-MR, ReloadSwiss RS 52, Hodgdon LEVERevolution rank at the top here: for .338 Weatherby RPM with the .338 | 210gr | Swift Scirocco 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.