Load Specifications
Bullet Manufacturer:Nosler
Bullet Weight:225 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:1:15.5
Load data in caliber .338 Weatherby RPM with .338 | 225gr | Nosler Partition bullet and 107 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are ReloadSwiss RS 60, Alliant Power Pro 2000-MR and ReloadSwiss RS 52.
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>> | 86% | 55,666 psi | 86% | 2530 fps | 100% |
| Accurate 2460 | <<locked>> | 84% | 57,870 psi | 89% | 2605 fps | 100% |
| Accurate 2495 | <<locked>> | 92% | 57,435 psi | 88% | 2595 fps | 100% |
| Accurate 2520 | <<locked>> | 86% | 56,101 psi | 86% | 2621 fps | 100% |
| Accurate 2700 | <<locked>> | 92% | 57,232 psi | 88% | 2602 fps | 97.2% |
| Accurate 4064 | <<locked>> | 94% | 57,261 psi | 88% | 2641 fps | 100% |
| Accurate 4350ᴾ | <<locked>> | 100% | 53,127 psi | 82% | 2671 fps | 99.4% |
| Accurate LT-30 | <<locked>> | 82% | 57,827 psi | 89% | 2516 fps | 100% |
| Accurate LT-32 | <<locked>> | 82% | 58,291 psi | 90% | 2543 fps | 100% |
| ADI AR 2206H | <<locked>> | 90% | 58,146 psi | 89% | 2674 fps | 100% |
| ADI AR 2208 | <<locked>> | 94% | 55,579 psi | 86% | 2625 fps | 99.8% |
| ADI Benchmark 8208 | <<locked>> | 88% | 57,174 psi | 88% | 2628 fps | 100% |
| Alliant AR-Comp | <<locked>> | 88% | 58,015 psi | 89% | 2602 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 82% | 55,782 psi | 86% | 2680 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 92% | 57,972 psi | 89% | 2789 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 94% | 55,332 psi | 85% | 2644 fps | 100% |
| Alliant Reloder-10x | <<locked>> | 84% | 58,813 psi | 90% | 2575 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 92% | 56,057 psi | 86% | 2667 fps | 99.9% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 51,401 psi | 79% | 2674 fps | 99.5% |
| Alliant Reloder-17 | <<locked>> | 98% | 56,086 psi | 86% | 2762 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 36,579 psi | 56% | 2428 fps | 98% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 40,408 psi | 62% | 2562 fps | 96.8% |
| Baschieri & Pellagri 106 | <<locked>> | 82% | 57,232 psi | 88% | 2520 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 90% | 58,015 psi | 89% | 2690 fps | 99.8% |
| Bofors RP3 | <<locked>> | 94% | 56,072 psi | 86% | 2664 fps | 100% |
| Bofors RP7 | <<locked>> | 98% | 56,217 psi | 86% | 2631 fps | 97.3% |
| Hodgdon Benchmark | <<locked>> | 86% | 55,738 psi | 86% | 2566 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 88% | 56,478 psi | 87% | 2657 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 86% | 58,595 psi | 90% | 2753 fps | 100% |
| Hodgdon H322 | <<locked>> | 84% | 58,131 psi | 89% | 2618 fps | 100% |
| Hodgdon H335 | <<locked>> | 82% | 55,535 psi | 85% | 2602 fps | 100% |
| Hodgdon H380 | <<locked>> | 94% | 57,116 psi | 88% | 2674 fps | 99.5% |
| Hodgdon H414ᴾ | <<locked>> | 100% | 56,057 psi | 86% | 2717 fps | 98% |
| Hodgdon H4350 | <<locked>> | 98% | 57,334 psi | 88% | 2684 fps | 96.9% |
| Hodgdon H4895 | <<locked>> | 90% | 58,682 psi | 90% | 2684 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 47,645 psi | 73% | 2559 fps | 99.7% |
| Hodgdon LEVERevolution | <<locked>> | 92% | 57,856 psi | 89% | 2713 fps | 100% |
| Hodgdon Superformanceᴾ | <<locked>> | 100% | 57,551 psi | 89% | 2759 fps | 97.8% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,331 psi | 54% | 1572 fps | 100% |
| Hodgdon VARGET | <<locked>> | 90% | 56,449 psi | 87% | 2638 fps | 100% |
| IMR 3031 | <<locked>> | 90% | 58,740 psi | 90% | 2664 fps | 100% |
| IMR 4064 | <<locked>> | 94% | 58,581 psi | 90% | 2654 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 90% | 55,448 psi | 85% | 2592 fps | 97.7% |
| IMR 4198 | <<locked>> | 82% | 55,477 psi | 85% | 2493 fps | 100% |
| IMR 4350ᴾ | <<locked>> | 100% | 52,779 psi | 81% | 2605 fps | 96.7% |
| IMR 4451 Enduron | <<locked>> | 98% | 58,175 psi | 89% | 2657 fps | 98% |
| IMR 4831ᴾ | <<locked>> | 100% | 50,125 psi | 77% | 2612 fps | 99.2% |
| IMR 4895 | <<locked>> | 92% | 57,464 psi | 88% | 2694 fps | 100% |
| IMR 8208 XBR | <<locked>> | 88% | 57,174 psi | 88% | 2628 fps | 100% |
| Lovex D073.5 | <<locked>> | 84% | 57,667 psi | 89% | 2618 fps | 100% |
| Lovex D073.6 | <<locked>> | 90% | 57,986 psi | 89% | 2651 fps | 100% |
| Lovex S060 | <<locked>> | 90% | 57,754 psi | 89% | 2602 fps | 100% |
| Lovex S062 | <<locked>> | 94% | 58,131 psi | 89% | 2648 fps | 100% |
| Lovex S065ᴾ | <<locked>> | 100% | 57,377 psi | 88% | 2654 fps | 99% |
| Lovex S070ᴾ | <<locked>> | 100% | 54,766 psi | 84% | 2638 fps | 97.9% |
| Norma 201 | <<locked>> | 90% | 56,971 psi | 88% | 2625 fps | 100% |
| Norma 202 | <<locked>> | 90% | 57,464 psi | 88% | 2621 fps | 100% |
| Norma 203B | <<locked>> | 94% | 58,813 psi | 90% | 2700 fps | 100% |
| Norma URPᴾ | <<locked>> | 100% | 52,417 psi | 81% | 2661 fps | 99.3% |
| Ramshot Big Game | <<locked>> | 92% | 55,796 psi | 86% | 2680 fps | 99.9% |
| Ramshot Hunterᴾ | <<locked>> | 100% | 51,314 psi | 79% | 2654 fps | 98% |
| Ramshot TAC | <<locked>> | 88% | 57,798 psi | 89% | 2651 fps | 99.2% |
| Ramshot Wild Boar | <<locked>> | 88% | 57,174 psi | 88% | 2664 fps | 100% |
| Ramshot X-Terminator | <<locked>> | 86% | 58,494 psi | 90% | 2635 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 35,708 psi | 55% | 1608 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 84% | 56,826 psi | 87% | 2608 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 94% | 57,464 psi | 88% | 2654 fps | 98.5% |
| ReloadSwiss RS 52 | <<locked>> | 90% | 56,434 psi | 87% | 2730 fps | 99.9% |
| ReloadSwiss RS 60 | <<locked>> | 96% | 55,767 psi | 86% | 2759 fps | 100% |
| ReloadSwiss RS 62ᴾ | <<locked>> | 100% | 52,417 psi | 81% | 2687 fps | 99.2% |
| ReloadSwiss RS 70ᴾ | <<locked>> | 100% | 52,924 psi | 81% | 2717 fps | 99% |
| Rottweil R 901 | <<locked>> | 88% | 57,885 psi | 89% | 2602 fps | 100% |
| Rottweil R 902 | <<locked>> | 92% | 57,348 psi | 88% | 2618 fps | 100% |
| Rottweil R 903 | <<locked>> | 96% | 55,651 psi | 86% | 2651 fps | 100% |
| Rottweil R 907 | <<locked>> | 98% | 56,217 psi | 86% | 2631 fps | 97.3% |
| Shooters World Long Rifleᴾ | <<locked>> | 100% | 57,377 psi | 88% | 2654 fps | 99% |
| Shooters World Match Rifle | <<locked>> | 90% | 57,986 psi | 89% | 2651 fps | 100% |
| Shooters World Precision | <<locked>> | 94% | 58,131 psi | 89% | 2648 fps | 100% |
| Shooters World SW4350ᴾ | <<locked>> | 100% | 54,766 psi | 84% | 2638 fps | 97.9% |
| Shooters World Tactical Rifle | <<locked>> | 82% | 56,521 psi | 87% | 2585 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 96% | 57,537 psi | 89% | 2710 fps | 100% |
| SNPE Vectan SP 3 | <<locked>> | 82% | 56,333 psi | 87% | 2556 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 88% | 56,159 psi | 86% | 2631 fps | 99.3% |
| SNPE Vectan SP 9 | <<locked>> | 90% | 56,536 psi | 87% | 2648 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 88% | 55,434 psi | 85% | 2523 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 96% | 58,537 psi | 90% | 2559 fps | 100% |
| SNPE Vectan Tubal 7000ᴾ | <<locked>> | 100% | 58,030 psi | 89% | 2612 fps | 98% |
| Somchem S321 | <<locked>> | 84% | 55,056 psi | 85% | 2615 fps | 100% |
| Somchem S335 | <<locked>> | 90% | 57,914 psi | 89% | 2562 fps | 100% |
| Somchem S341 | <<locked>> | 88% | 55,434 psi | 85% | 2618 fps | 99.9% |
| Somchem S355 | <<locked>> | 96% | 55,941 psi | 86% | 2648 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 46,673 psi | 72% | 2612 fps | 100% |
| Vihtavuori N130 | <<locked>> | 86% | 58,349 psi | 90% | 2526 fps | 100% |
| Vihtavuori N133 | <<locked>> | 88% | 55,550 psi | 85% | 2507 fps | 100% |
| Vihtavuori N135 | <<locked>> | 92% | 56,913 psi | 88% | 2582 fps | 100% |
| Vihtavuori N140 | <<locked>> | 92% | 58,044 psi | 89% | 2602 fps | 100% |
| Vihtavuori N150 | <<locked>> | 98% | 57,725 psi | 89% | 2628 fps | 100% |
| Vihtavuori N160ᴾ | <<locked>> | 100% | 55,042 psi | 85% | 2657 fps | 99.5% |
| Vihtavuori N530 | <<locked>> | 88% | 57,812 psi | 89% | 2628 fps | 100% |
| Vihtavuori N540 | <<locked>> | 92% | 55,970 psi | 86% | 2602 fps | 100% |
| Vihtavuori N550ᴾ | <<locked>> | 100% | 53,954 psi | 83% | 2661 fps | 99.3% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 39,407 psi | 61% | 2497 fps | 97.9% |
| Winchester 6.5 StaBALLᴾ | <<locked>> | 100% | 55,680 psi | 86% | 2641 fps | 100% |
| Winchester 748 | <<locked>> | 88% | 57,682 psi | 89% | 2674 fps | 100% |
| Winchester 760ᴾ | <<locked>> | 100% | 56,347 psi | 87% | 2720 fps | 98% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 32,677 psi | 50% | 2411 fps | 97.2% |
| Winchester StaBALL Match | <<locked>> | 90% | 56,507 psi | 87% | 2657 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% | 46,267 psi | 71% | 2405 fps | 100% |
| Accurate 2460 | <<locked>> | 80% | 50,691 psi | 78% | 2513 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 39,030 psi | 60% | 2339 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 45,716 psi | 70% | 2477 fps | 100% |
| Accurate 2700 | <<locked>> | 86% | 47,181 psi | 73% | 2451 fps | 95.1% |
| Accurate 4064 | <<locked>> | 80% | 36,927 psi | 57% | 2333 fps | 100% |
| Accurate 4350 | <<locked>> | 88% | 35,027 psi | 54% | 2359 fps | 95.8% |
| Accurate LT-30 | <<locked>> | 80% | 54,563 psi | 84% | 2474 fps | 100% |
| Accurate LT-32 | <<locked>> | 80% | 54,984 psi | 85% | 2500 fps | 100% |
| ADI AR 2206H | <<locked>> | 80% | 42,670 psi | 66% | 2434 fps | 98.8% |
| ADI AR 2208 | <<locked>> | 80% | 36,332 psi | 56% | 2297 fps | 96.8% |
| ADI Benchmark 8208 | <<locked>> | 80% | 44,686 psi | 69% | 2444 fps | 99.7% |
| Alliant AR-Comp | <<locked>> | 80% | 44,585 psi | 69% | 2431 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 80% | 52,185 psi | 80% | 2628 fps | 100% |
| Alliant Power Pro 2000-MR | 54.8 gr | 80% | 38,479 psi | 59% | 2454 fps | 97.2% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 35,665 psi | 55% | 2316 fps | 98.2% |
| Alliant Reloder-10x | <<locked>> | 80% | 52,199 psi | 80% | 2493 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 38,479 psi | 59% | 2375 fps | 97.6% |
| Alliant Reloder-16 | <<locked>> | 86% | 33,547 psi | 52% | 2320 fps | 95.1% |
| Alliant Reloder-17 | <<locked>> | 80% | 30,792 psi | 47% | 2280 fps | 95.8% |
| Alliant Reloder-23 | <<locked>> | 94% | 30,530 psi | 47% | 2277 fps | 95.5% |
| Alliant Reloder-26 | <<locked>> | 98% | 37,710 psi | 58% | 2503 fps | 95.8% |
| Baschieri & Pellagri 106 | <<locked>> | 80% | 53,708 psi | 83% | 2474 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 41,626 psi | 64% | 2434 fps | 97.8% |
| Bofors RP3 | <<locked>> | 80% | 35,143 psi | 54% | 2316 fps | 98.1% |
| Bofors RP7 | <<locked>> | 92% | 46,717 psi | 72% | 2484 fps | 95.3% |
| Hodgdon Benchmark | <<locked>> | 80% | 46,543 psi | 72% | 2434 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 43,134 psi | 66% | 2461 fps | 99.8% |
| Hodgdon CFE223 | <<locked>> | 80% | 47,514 psi | 73% | 2592 fps | 99.2% |
| Hodgdon H322 | <<locked>> | 80% | 50,981 psi | 78% | 2530 fps | 100% |
| Hodgdon H335 | <<locked>> | 80% | 51,895 psi | 80% | 2552 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 36,172 psi | 56% | 2320 fps | 95.5% |
| Hodgdon H414 | <<locked>> | 92% | 43,323 psi | 67% | 2513 fps | 95.2% |
| Hodgdon H4350 | <<locked>> | 94% | 50,546 psi | 78% | 2585 fps | 95.5% |
| Hodgdon H4895 | <<locked>> | 80% | 43,047 psi | 66% | 2444 fps | 99.3% |
| Hodgdon Hybrid 100V | <<locked>> | 84% | 28,834 psi | 44% | 2178 fps | 95.1% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 38,899 psi | 60% | 2418 fps | 99% |
| Hodgdon Superformance | <<locked>> | 94% | 46,441 psi | 71% | 2582 fps | 95.3% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,179 psi | 40% | 1398 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 41,278 psi | 64% | 2402 fps | 98.9% |
| IMR 3031 | <<locked>> | 80% | 42,366 psi | 65% | 2438 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 38,145 psi | 59% | 2329 fps | 97.5% |
| IMR 4166 Enduron | <<locked>> | 82% | 43,279 psi | 67% | 2395 fps | 95% |
| IMR 4198 | <<locked>> | 80% | 52,460 psi | 81% | 2454 fps | 100% |
| IMR 4350 | <<locked>> | 96% | 46,543 psi | 72% | 2503 fps | 95.3% |
| IMR 4451 Enduron | <<locked>> | 90% | 45,629 psi | 70% | 2467 fps | 95.6% |
| IMR 4831 | <<locked>> | 88% | 34,069 psi | 52% | 2320 fps | 95.5% |
| IMR 4895 | <<locked>> | 80% | 39,378 psi | 61% | 2402 fps | 98.3% |
| IMR 8208 XBR | <<locked>> | 80% | 44,686 psi | 69% | 2444 fps | 99.7% |
| Lovex D073.5 | <<locked>> | 80% | 50,328 psi | 77% | 2520 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 41,611 psi | 64% | 2418 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 42,946 psi | 66% | 2379 fps | 98.9% |
| Lovex S062 | <<locked>> | 80% | 37,956 psi | 58% | 2333 fps | 99% |
| Lovex S065 | <<locked>> | 88% | 39,813 psi | 61% | 2369 fps | 95.7% |
| Lovex S070 | <<locked>> | 92% | 42,757 psi | 66% | 2444 fps | 95.2% |
| Norma 201 | <<locked>> | 80% | 41,887 psi | 64% | 2392 fps | 99.5% |
| Norma 202 | <<locked>> | 80% | 41,901 psi | 64% | 2398 fps | 100% |
| Norma 203B | <<locked>> | 80% | 37,840 psi | 58% | 2365 fps | 97.9% |
| Norma URP | <<locked>> | 88% | 35,534 psi | 55% | 2362 fps | 95.8% |
| Ramshot Big Game | <<locked>> | 80% | 37,130 psi | 57% | 2372 fps | 97.5% |
| Ramshot Hunter | <<locked>> | 92% | 39,523 psi | 61% | 2444 fps | 95% |
| Ramshot TAC | <<locked>> | 80% | 44,498 psi | 68% | 2444 fps | 97.1% |
| Ramshot Wild Boar | <<locked>> | 80% | 43,874 psi | 67% | 2464 fps | 99% |
| Ramshot X-Terminator | <<locked>> | 80% | 48,312 psi | 74% | 2490 fps | 99.4% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,614 psi | 41% | 1437 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 50,082 psi | 77% | 2516 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 84% | 41,655 psi | 64% | 2405 fps | 95.4% |
| ReloadSwiss RS 52 | 53.2 gr | 80% | 40,089 psi | 62% | 2467 fps | 98% |
| ReloadSwiss RS 60 | 54 gr | 80% | 32,764 psi | 50% | 2343 fps | 99% |
| ReloadSwiss RS 62 | <<locked>> | 88% | 34,824 psi | 54% | 2372 fps | 95.2% |
| ReloadSwiss RS 70 | <<locked>> | 90% | 37,753 psi | 58% | 2434 fps | 95.2% |
| Rottweil R 901 | <<locked>> | 80% | 45,716 psi | 70% | 2431 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 39,769 psi | 61% | 2346 fps | 99.2% |
| Rottweil R 903 | <<locked>> | 80% | 33,127 psi | 51% | 2267 fps | 97.3% |
| Rottweil R 907 | <<locked>> | 92% | 46,717 psi | 72% | 2484 fps | 95.3% |
| Shooters World Long Rifle | <<locked>> | 88% | 39,813 psi | 61% | 2369 fps | 95.7% |
| Shooters World Match Rifle | <<locked>> | 80% | 41,611 psi | 64% | 2418 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 37,956 psi | 58% | 2333 fps | 99% |
| Shooters World SW4350 | <<locked>> | 92% | 42,757 psi | 66% | 2444 fps | 95.2% |
| Shooters World Tactical Rifle | <<locked>> | 80% | 52,750 psi | 81% | 2533 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 34,185 psi | 53% | 2313 fps | 96.7% |
| SNPE Vectan SP 3 | <<locked>> | 80% | 53,055 psi | 82% | 2513 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 42,670 psi | 66% | 2421 fps | 97.2% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 41,191 psi | 63% | 2408 fps | 98.6% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 43,323 psi | 67% | 2352 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 35,882 psi | 55% | 2231 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 92% | 44,570 psi | 69% | 2415 fps | 95.5% |
| Somchem S321 | <<locked>> | 80% | 48,124 psi | 74% | 2516 fps | 100% |
| Somchem S335 | <<locked>> | 80% | 42,902 psi | 66% | 2352 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 42,438 psi | 65% | 2421 fps | 98.7% |
| Somchem S355 | <<locked>> | 80% | 34,185 psi | 53% | 2277 fps | 97.4% |
| Somchem S365 | <<locked>> | 82% | 26,295 psi | 40% | 2162 fps | 95.4% |
| Vihtavuori N130 | <<locked>> | 80% | 48,921 psi | 75% | 2405 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 43,569 psi | 67% | 2346 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 39,131 psi | 60% | 2333 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 39,726 psi | 61% | 2343 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 32,329 psi | 50% | 2218 fps | 98.1% |
| Vihtavuori N160 | <<locked>> | 86% | 34,824 psi | 54% | 2313 fps | 95.4% |
| Vihtavuori N530 | <<locked>> | 80% | 44,599 psi | 69% | 2438 fps | 99.7% |
| Vihtavuori N540 | <<locked>> | 80% | 38,232 psi | 59% | 2333 fps | 99.9% |
| Vihtavuori N550 | <<locked>> | 86% | 34,185 psi | 53% | 2313 fps | 95% |
| Vihtavuori N555 | <<locked>> | 94% | 32,518 psi | 50% | 2346 fps | 95.6% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 28,819 psi | 44% | 2146 fps | 95.1% |
| Winchester 748 | <<locked>> | 80% | 44,135 psi | 68% | 2480 fps | 100% |
| Winchester 760 | <<locked>> | 92% | 43,323 psi | 67% | 2513 fps | 95.2% |
| Winchester StaBALL HD | <<locked>> | 98% | 30,574 psi | 47% | 2349 fps | 96% |
| Winchester StaBALL Match | <<locked>> | 80% | 40,495 psi | 62% | 2411 fps | 98.9% |
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 107 powders for .338 Weatherby RPM loaded with the .338 | 225gr | Nosler Partition. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 2,789 fps; across all powders the maximum-charge window runs from 1,572 fps to 2,789 fps. Accurate 4350 gives the best case fill at 100 %, and 107 of the 107 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (448 MPa), the top charges use 50–90 %, leaving at least 10 % headroom. The 225.0 gr projectile in 0.338" calls for a 1:15.5 twist; slower twists will usually not stabilise this weight. Accurate 4350, Alliant Reloder-16, Alliant Reloder-23 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 60, Alliant Power Pro 2000-MR, ReloadSwiss RS 52 rank at the top here: for .338 Weatherby RPM with the .338 | 225gr | Nosler Partition 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.