Load Specifications
Load data in caliber .300 WSM with .308 | 220gr | Nosler Partition bullet and 96 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are IMR 4831, Alliant Reloder-26 and Ramshot Grand.
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 2495 | <<locked>> | 82% | 57,043 psi | 89% | 2451 fps | 100% |
| Accurate 2700 | <<locked>> | 86% | 55,666 psi | 87% | 2493 fps | 99.6% |
| Accurate 3100ᴾ | <<locked>> | 100% | 55,912 psi | 88% | 2579 fps | 100% |
| Accurate 4064 | <<locked>> | 84% | 57,348 psi | 90% | 2500 fps | 100% |
| Accurate 4350 | <<locked>> | 90% | 54,476 psi | 85% | 2569 fps | 100% |
| Accurate MAGPROᴾ | <<locked>> | 100% | 54,795 psi | 86% | 2667 fps | 96.9% |
| ADI AR 2208 | <<locked>> | 86% | 57,246 psi | 90% | 2536 fps | 100% |
| ADI AR 2209 | <<locked>> | 96% | 55,245 psi | 87% | 2615 fps | 99.2% |
| ADI AR 2213ᴾ | <<locked>> | 100% | 56,507 psi | 89% | 2664 fps | 98.6% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 36,463 psi | 57% | 2369 fps | 97.1% |
| Alliant Power Pro 2000-MR | <<locked>> | 82% | 56,710 psi | 89% | 2651 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 84% | 54,621 psi | 86% | 2510 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 82% | 54,781 psi | 86% | 2530 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 92% | 55,376 psi | 87% | 2618 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 88% | 56,565 psi | 89% | 2635 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 96% | 54,781 psi | 86% | 2605 fps | 99.2% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 55,579 psi | 87% | 2661 fps | 99.4% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 52,562 psi | 82% | 2589 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 45,745 psi | 72% | 2539 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 98% | 56,420 psi | 88% | 2723 fps | 100% |
| Bofors RP15ᴾ | <<locked>> | 100% | 50,937 psi | 80% | 2595 fps | 98.8% |
| Bofors RP3 | <<locked>> | 84% | 55,535 psi | 87% | 2530 fps | 100% |
| Bofors RP30ᴾ | <<locked>> | 100% | 41,568 psi | 65% | 2470 fps | 96.3% |
| Bofors RP5ᴾ | <<locked>> | 100% | 55,579 psi | 87% | 2661 fps | 99.4% |
| Bofors RP7 | <<locked>> | 88% | 54,737 psi | 86% | 2523 fps | 99.6% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 42,308 psi | 66% | 2428 fps | 96.3% |
| Hodgdon H380 | <<locked>> | 84% | 55,854 psi | 88% | 2546 fps | 100% |
| Hodgdon H414 | <<locked>> | 86% | 54,041 psi | 85% | 2582 fps | 99.8% |
| Hodgdon H4350 | <<locked>> | 90% | 54,781 psi | 86% | 2559 fps | 99.3% |
| Hodgdon H4831ᴾ | <<locked>> | 100% | 52,170 psi | 82% | 2549 fps | 97.3% |
| Hodgdon H4831 SC | <<locked>> | 98% | 55,492 psi | 87% | 2595 fps | 97.9% |
| Hodgdon Hybrid 100V | <<locked>> | 94% | 55,550 psi | 87% | 2543 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 84% | 57,522 psi | 90% | 2579 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 44,846 psi | 70% | 2582 fps | 98.6% |
| Hodgdon Superformance | <<locked>> | 90% | 56,913 psi | 89% | 2657 fps | 99.9% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,637 psi | 57% | 1549 fps | 100% |
| Hodgdon VARGET | <<locked>> | 84% | 56,608 psi | 89% | 2523 fps | 100% |
| IMR 3031 | <<locked>> | 82% | 56,391 psi | 88% | 2490 fps | 100% |
| IMR 4064 | <<locked>> | 86% | 56,057 psi | 88% | 2510 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 86% | 54,766 psi | 86% | 2497 fps | 99.8% |
| IMR 4350 | <<locked>> | 92% | 55,753 psi | 87% | 2556 fps | 99.7% |
| IMR 4451 Enduron | <<locked>> | 88% | 56,391 psi | 88% | 2546 fps | 99.9% |
| IMR 4831 | <<locked>> | 96% | 55,956 psi | 88% | 2572 fps | 100% |
| IMR 4895 | <<locked>> | 82% | 56,173 psi | 88% | 2552 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 96% | 54,650 psi | 86% | 2549 fps | 97.9% |
| IMR 7828 SSC | <<locked>> | 98% | 54,302 psi | 85% | 2648 fps | 98.4% |
| Lovex S062 | <<locked>> | 84% | 56,855 psi | 89% | 2510 fps | 100% |
| Lovex S065 | <<locked>> | 90% | 56,550 psi | 89% | 2543 fps | 100% |
| Lovex S070 | <<locked>> | 90% | 54,418 psi | 85% | 2536 fps | 99.9% |
| Lovex S071ᴾ | <<locked>> | 100% | 46,557 psi | 73% | 2451 fps | 99.6% |
| Norma 203B | <<locked>> | 84% | 57,638 psi | 90% | 2562 fps | 100% |
| Norma 204 | <<locked>> | 92% | 56,434 psi | 88% | 2608 fps | 99.2% |
| Norma MRP | <<locked>> | 98% | 55,071 psi | 86% | 2684 fps | 99.9% |
| Norma URP | <<locked>> | 92% | 56,855 psi | 89% | 2602 fps | 100% |
| Ramshot Big Game | <<locked>> | 82% | 54,723 psi | 86% | 2543 fps | 100% |
| Ramshot Grand | <<locked>> | 96% | 54,056 psi | 85% | 2654 fps | 98.7% |
| Ramshot Hunter | <<locked>> | 92% | 55,390 psi | 87% | 2605 fps | 100% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 54,578 psi | 86% | 2635 fps | 99.7% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,333 psi | 59% | 1585 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 84% | 55,709 psi | 87% | 2536 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 86% | 56,188 psi | 88% | 2625 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 90% | 54,389 psi | 85% | 2592 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 92% | 56,318 psi | 88% | 2667 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 44,643 psi | 70% | 2575 fps | 99.3% |
| Rottweil R 902 | <<locked>> | 82% | 55,376 psi | 87% | 2474 fps | 100% |
| Rottweil R 903 | <<locked>> | 86% | 55,695 psi | 87% | 2526 fps | 100% |
| Rottweil R 904 | <<locked>> | 96% | 57,014 psi | 89% | 2585 fps | 98.7% |
| Rottweil R 905 | <<locked>> | 98% | 57,740 psi | 90% | 2644 fps | 99.6% |
| Rottweil R 907 | <<locked>> | 88% | 54,737 psi | 86% | 2523 fps | 99.6% |
| Shooters World Long Rifle | <<locked>> | 90% | 56,550 psi | 89% | 2543 fps | 100% |
| Shooters World Precision | <<locked>> | 84% | 56,855 psi | 89% | 2510 fps | 100% |
| Shooters World SW4350 | <<locked>> | 90% | 54,418 psi | 85% | 2536 fps | 99.9% |
| SNPE Vectan SP 11 | <<locked>> | 86% | 57,203 psi | 90% | 2582 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 86% | 56,405 psi | 88% | 2411 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 90% | 55,912 psi | 88% | 2500 fps | 99.9% |
| SNPE Vectan Tubal 8000 | <<locked>> | 98% | 57,246 psi | 90% | 2638 fps | 99.5% |
| Somchem S355 | <<locked>> | 86% | 55,579 psi | 87% | 2520 fps | 100% |
| Somchem S361 | <<locked>> | 94% | 55,027 psi | 86% | 2533 fps | 97.7% |
| Somchem S365 | <<locked>> | 94% | 56,130 psi | 88% | 2598 fps | 100% |
| Somchem S385 | <<locked>> | 96% | 54,534 psi | 85% | 2569 fps | 99.6% |
| Unknown powder | <<locked>> | 90% | 57,305 psi | 90% | 2602 fps | 100% |
| Vihtavuori N133 | <<locked>> | 82% | 55,738 psi | 87% | 2385 fps | 100% |
| Vihtavuori N135 | <<locked>> | 82% | 56,043 psi | 88% | 2434 fps | 100% |
| Vihtavuori N140 | <<locked>> | 82% | 55,303 psi | 87% | 2444 fps | 100% |
| Vihtavuori N150 | <<locked>> | 92% | 57,145 psi | 90% | 2503 fps | 100% |
| Vihtavuori N160 | <<locked>> | 88% | 54,114 psi | 85% | 2526 fps | 100% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 51,895 psi | 81% | 2523 fps | 99.2% |
| Vihtavuori N540 | <<locked>> | 82% | 54,940 psi | 86% | 2470 fps | 100% |
| Vihtavuori N550 | <<locked>> | 88% | 54,665 psi | 86% | 2572 fps | 100% |
| Vihtavuori N555 | <<locked>> | 98% | 55,216 psi | 87% | 2612 fps | 100% |
| Vihtavuori N560ᴾ | <<locked>> | 100% | 55,840 psi | 88% | 2687 fps | 98.3% |
| Vihtavuori N565ᴾ | <<locked>> | 100% | 47,253 psi | 74% | 2543 fps | 96.9% |
| Winchester 6.5 StaBALL | <<locked>> | 90% | 54,665 psi | 86% | 2516 fps | 100% |
| Winchester 760 | <<locked>> | 86% | 54,041 psi | 85% | 2582 fps | 99.8% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 47,805 psi | 75% | 2657 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 96% | 56,449 psi | 88% | 2589 fps | 99.3% |
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 2495 | <<locked>> | 80% | 53,403 psi | 84% | 2405 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 45,890 psi | 72% | 2349 fps | 98.4% |
| Accurate 3100 | <<locked>> | 80% | 28,587 psi | 45% | 2096 fps | 95.1% |
| Accurate 4064 | <<locked>> | 80% | 50,647 psi | 79% | 2418 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 38,841 psi | 61% | 2323 fps | 99.5% |
| Accurate MAGPRO | <<locked>> | 96% | 47,674 psi | 75% | 2556 fps | 95.3% |
| ADI AR 2208 | <<locked>> | 80% | 47,514 psi | 74% | 2402 fps | 100% |
| ADI AR 2209 | <<locked>> | 84% | 37,565 psi | 59% | 2310 fps | 95.5% |
| ADI AR 2213 | <<locked>> | 92% | 43,323 psi | 68% | 2451 fps | 95.8% |
| ADI AR 2225 | <<locked>> | 96% | 32,155 psi | 50% | 2260 fps | 95% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 52,997 psi | 83% | 2602 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 48,283 psi | 76% | 2425 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 51,372 psi | 81% | 2484 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 37,753 psi | 59% | 2333 fps | 99.6% |
| Alliant Reloder-17 | <<locked>> | 80% | 42,743 psi | 67% | 2438 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 84% | 37,347 psi | 59% | 2306 fps | 95.6% |
| Alliant Reloder-22 | <<locked>> | 88% | 37,536 psi | 59% | 2356 fps | 95.8% |
| Alliant Reloder-23 | <<locked>> | 80% | 27,760 psi | 44% | 2126 fps | 98.4% |
| Alliant Reloder-25 | <<locked>> | 86% | 29,515 psi | 46% | 2188 fps | 96% |
| Alliant Reloder-26 | 54.9 gr | 80% | 29,631 psi | 46% | 2231 fps | 97.1% |
| Bofors RP15 | <<locked>> | 90% | 37,043 psi | 58% | 2346 fps | 95.5% |
| Bofors RP3 | <<locked>> | 80% | 48,704 psi | 76% | 2434 fps | 100% |
| Bofors RP30 | <<locked>> | 98% | 38,899 psi | 61% | 2418 fps | 95.4% |
| Bofors RP5 | <<locked>> | 88% | 37,536 psi | 59% | 2356 fps | 95.8% |
| Bofors RP7 | <<locked>> | 80% | 42,757 psi | 67% | 2333 fps | 98% |
| Hodgdon H1000 | <<locked>> | 98% | 39,595 psi | 62% | 2375 fps | 95.4% |
| Hodgdon H380 | <<locked>> | 80% | 49,081 psi | 77% | 2451 fps | 100% |
| Hodgdon H414 | <<locked>> | 80% | 44,266 psi | 69% | 2431 fps | 98.8% |
| Hodgdon H4350 | <<locked>> | 80% | 40,118 psi | 63% | 2316 fps | 96.7% |
| Hodgdon H4831 | <<locked>> | 94% | 43,192 psi | 68% | 2402 fps | 95.1% |
| Hodgdon H4831 SC | <<locked>> | 92% | 45,426 psi | 71% | 2441 fps | 95.8% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 35,418 psi | 56% | 2238 fps | 99.8% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 50,560 psi | 79% | 2487 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 94% | 36,970 psi | 58% | 2411 fps | 96% |
| Hodgdon Superformance | <<locked>> | 80% | 39,610 psi | 62% | 2382 fps | 97.6% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,412 psi | 43% | 1381 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 50,299 psi | 79% | 2438 fps | 100% |
| IMR 3031 | <<locked>> | 80% | 52,982 psi | 83% | 2451 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 46,833 psi | 73% | 2382 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 80% | 45,948 psi | 72% | 2362 fps | 99% |
| IMR 4350 | <<locked>> | 80% | 38,421 psi | 60% | 2274 fps | 97% |
| IMR 4451 Enduron | <<locked>> | 80% | 44,063 psi | 69% | 2356 fps | 98.6% |
| IMR 4831 | 48.9 gr | 80% | 34,026 psi | 53% | 2215 fps | 98.7% |
| IMR 4895 | <<locked>> | 80% | 52,707 psi | 83% | 2507 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 88% | 42,627 psi | 67% | 2356 fps | 95.2% |
| IMR 7828 SSC | <<locked>> | 90% | 41,568 psi | 65% | 2431 fps | 95.4% |
| Lovex S062 | <<locked>> | 80% | 50,531 psi | 79% | 2428 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 41,626 psi | 65% | 2313 fps | 99.1% |
| Lovex S070 | <<locked>> | 80% | 39,972 psi | 63% | 2303 fps | 98.1% |
| Lovex S071 | <<locked>> | 86% | 29,979 psi | 47% | 2129 fps | 95.8% |
| Norma 203B | <<locked>> | 80% | 50,734 psi | 80% | 2474 fps | 100% |
| Norma 204 | <<locked>> | 80% | 37,768 psi | 59% | 2297 fps | 95.4% |
| Norma MRP | <<locked>> | 82% | 32,010 psi | 50% | 2257 fps | 95.2% |
| Norma URP | <<locked>> | 80% | 38,667 psi | 61% | 2320 fps | 99.4% |
| Ramshot Big Game | <<locked>> | 80% | 51,329 psi | 80% | 2500 fps | 100% |
| Ramshot Grand | 60.4 gr | 88% | 40,364 psi | 63% | 2418 fps | 95.4% |
| Ramshot Hunter | <<locked>> | 80% | 37,376 psi | 59% | 2310 fps | 98.1% |
| Ramshot Magnum | <<locked>> | 88% | 35,070 psi | 55% | 2297 fps | 95.6% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,891 psi | 44% | 1414 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 48,892 psi | 77% | 2438 fps | 99.6% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 45,397 psi | 71% | 2480 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 38,638 psi | 61% | 2343 fps | 99.4% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 37,376 psi | 59% | 2356 fps | 99% |
| ReloadSwiss RS 76 | <<locked>> | 92% | 33,910 psi | 53% | 2339 fps | 95.9% |
| Rottweil R 902 | <<locked>> | 80% | 52,199 psi | 82% | 2434 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 45,934 psi | 72% | 2392 fps | 100% |
| Rottweil R 904 | <<locked>> | 86% | 41,611 psi | 65% | 2343 fps | 95.5% |
| Rottweil R 905 | <<locked>> | 84% | 36,448 psi | 57% | 2293 fps | 95.5% |
| Rottweil R 907 | <<locked>> | 80% | 42,757 psi | 67% | 2333 fps | 98% |
| Shooters World Long Rifle | <<locked>> | 80% | 41,626 psi | 65% | 2313 fps | 99.1% |
| Shooters World Precision | <<locked>> | 80% | 50,531 psi | 79% | 2428 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 39,972 psi | 63% | 2303 fps | 98.1% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 46,949 psi | 74% | 2441 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 47,065 psi | 74% | 2293 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 40,872 psi | 64% | 2267 fps | 98.1% |
| SNPE Vectan Tubal 8000 | <<locked>> | 84% | 36,100 psi | 57% | 2287 fps | 95.3% |
| Somchem S355 | <<locked>> | 80% | 46,050 psi | 72% | 2385 fps | 100% |
| Somchem S361 | <<locked>> | 88% | 45,165 psi | 71% | 2382 fps | 95.6% |
| Somchem S365 | <<locked>> | 80% | 35,172 psi | 55% | 2283 fps | 100% |
| Somchem S385 | <<locked>> | 82% | 34,737 psi | 54% | 2231 fps | 95.8% |
| Unknown powder | <<locked>> | 80% | 41,437 psi | 65% | 2365 fps | 99.5% |
| Vihtavuori N133 | <<locked>> | 80% | 52,489 psi | 82% | 2346 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 52,736 psi | 83% | 2395 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 51,880 psi | 81% | 2402 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 39,726 psi | 62% | 2257 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 41,611 psi | 65% | 2339 fps | 99.7% |
| Vihtavuori N165 | <<locked>> | 88% | 35,215 psi | 55% | 2238 fps | 95.5% |
| Vihtavuori N540 | <<locked>> | 80% | 51,590 psi | 81% | 2428 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 42,264 psi | 66% | 2382 fps | 99.7% |
| Vihtavuori N555 | <<locked>> | 80% | 30,719 psi | 48% | 2192 fps | 98.3% |
| Vihtavuori N560 | <<locked>> | 92% | 42,931 psi | 67% | 2474 fps | 95.4% |
| Vihtavuori N565 | <<locked>> | 96% | 41,336 psi | 65% | 2441 fps | 95.3% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 38,914 psi | 61% | 2287 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 44,266 psi | 69% | 2431 fps | 98.8% |
| Winchester StaBALL HD | <<locked>> | 80% | 24,526 psi | 38% | 2116 fps | 97.9% |
| Winchester Supreme 780 | <<locked>> | 84% | 36,927 psi | 58% | 2277 fps | 95.4% |
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 102 powders for .300 WSM loaded with the .308 | 220gr | Nosler Partition. Alliant Reloder-26 delivers the highest muzzle velocity at 2,723 fps; across all powders the maximum-charge window runs from 1,549 fps to 2,723 fps. Accurate 3100 gives the best case fill at 100 %, and 102 of the 102 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (440 MPa), the top charges use 50–90 %, leaving at least 10 % headroom. The 220.0 gr projectile in 0.308" calls for a 1:13.0 twist; slower twists will usually not stabilise this weight. Accurate 3100, Accurate MAGPRO, 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. IMR 4831, Alliant Reloder-26, Ramshot Grand rank at the top here: for .300 WSM with the .308 | 220gr | Nosler Partition they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, IMR 8133 Enduron, Norma 217, ReloadSwiss RS 80 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.