Load Specifications
Load data in caliber 7.5 x 55 Swiss with .308 | 203gr | Peregrine Plainsmaster (VLR-4) bullet and 97 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.
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Max Load - Barrel Length: 31"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2015 | <<locked>> | 82% | 47,036 psi | 85% | 2362 fps | 100% |
| Accurate 2495 | <<locked>> | 88% | 47,340 psi | 86% | 2421 fps | 100% |
| Accurate 2520 | <<locked>> | 84% | 49,472 psi | 90% | 2480 fps | 100% |
| Accurate 2700 | <<locked>> | 88% | 47,979 psi | 87% | 2428 fps | 97.3% |
| Accurate 3100ᴾ | <<locked>> | 100% | 34,693 psi | 63% | 2333 fps | 96.4% |
| Accurate 4064 | <<locked>> | 90% | 47,427 psi | 86% | 2467 fps | 100% |
| Accurate 4350ᴾ | <<locked>> | 100% | 49,647 psi | 90% | 2585 fps | 99.9% |
| ADI AR 2206H | <<locked>> | 86% | 48,994 psi | 89% | 2500 fps | 100% |
| ADI AR 2208 | <<locked>> | 90% | 47,239 psi | 86% | 2461 fps | 99.9% |
| ADI Benchmark 8208 | <<locked>> | 84% | 48,501 psi | 88% | 2457 fps | 100% |
| Alliant AR-Comp | <<locked>> | 84% | 48,356 psi | 88% | 2425 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 88% | 48,254 psi | 88% | 2608 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 92% | 49,676 psi | 90% | 2520 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 88% | 47,152 psi | 86% | 2497 fps | 99.9% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 48,965 psi | 89% | 2598 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 96% | 49,458 psi | 90% | 2628 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 34,374 psi | 62% | 2372 fps | 99.3% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 37,695 psi | 68% | 2507 fps | 98.5% |
| Baschieri & Pellagri 107 | <<locked>> | 86% | 48,472 psi | 88% | 2516 fps | 99.9% |
| Bofors RP3 | <<locked>> | 92% | 49,356 psi | 90% | 2530 fps | 100% |
| Bofors RP7 | <<locked>> | 94% | 47,398 psi | 86% | 2464 fps | 97.5% |
| Hodgdon Benchmark | <<locked>> | 82% | 47,572 psi | 86% | 2398 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 84% | 47,021 psi | 85% | 2484 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 82% | 48,443 psi | 88% | 2566 fps | 100% |
| Hodgdon H380 | <<locked>> | 90% | 47,456 psi | 86% | 2497 fps | 99.5% |
| Hodgdon H414 | <<locked>> | 96% | 46,601 psi | 85% | 2543 fps | 98.2% |
| Hodgdon H4350 | <<locked>> | 94% | 48,138 psi | 87% | 2513 fps | 97.1% |
| Hodgdon H4895 | <<locked>> | 86% | 49,429 psi | 90% | 2507 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 45,034 psi | 82% | 2484 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 88% | 48,225 psi | 88% | 2539 fps | 100% |
| Hodgdon Superformance | <<locked>> | 96% | 47,079 psi | 85% | 2572 fps | 97.8% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 34,940 psi | 63% | 1499 fps | 100% |
| Hodgdon VARGET | <<locked>> | 86% | 47,732 psi | 87% | 2467 fps | 100% |
| IMR 3031 | <<locked>> | 86% | 49,197 psi | 89% | 2487 fps | 100% |
| IMR 4064 | <<locked>> | 90% | 49,690 psi | 90% | 2484 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 86% | 46,847 psi | 85% | 2421 fps | 97.9% |
| IMR 4350 | <<locked>> | 98% | 47,166 psi | 86% | 2484 fps | 97.6% |
| IMR 4451 Enduron | <<locked>> | 94% | 49,501 psi | 90% | 2493 fps | 98.3% |
| IMR 4831ᴾ | <<locked>> | 100% | 47,355 psi | 86% | 2536 fps | 99.8% |
| IMR 4895 | <<locked>> | 88% | 48,327 psi | 88% | 2523 fps | 100% |
| IMR 8208 XBR | <<locked>> | 84% | 48,501 psi | 88% | 2457 fps | 100% |
| Lovex D073.6 | <<locked>> | 86% | 48,066 psi | 87% | 2474 fps | 100% |
| Lovex S060 | <<locked>> | 86% | 49,240 psi | 89% | 2434 fps | 100% |
| Lovex S062 | <<locked>> | 90% | 49,240 psi | 89% | 2480 fps | 100% |
| Lovex S065 | <<locked>> | 96% | 48,385 psi | 88% | 2487 fps | 99.2% |
| Lovex S070 | <<locked>> | 98% | 48,762 psi | 88% | 2516 fps | 98.5% |
| Norma 201 | <<locked>> | 86% | 48,022 psi | 87% | 2451 fps | 100% |
| Norma 202 | <<locked>> | 86% | 48,399 psi | 88% | 2451 fps | 100% |
| Norma 203B | <<locked>> | 90% | 49,284 psi | 89% | 2526 fps | 100% |
| Norma 204 | <<locked>> | 98% | 47,514 psi | 86% | 2526 fps | 96.4% |
| Norma MRPᴾ | <<locked>> | 100% | 38,377 psi | 70% | 2474 fps | 96% |
| Norma URPᴾ | <<locked>> | 100% | 49,443 psi | 90% | 2582 fps | 99.9% |
| Ramshot Big Game | <<locked>> | 90% | 49,588 psi | 90% | 2552 fps | 100% |
| Ramshot Hunterᴾ | <<locked>> | 100% | 48,399 psi | 88% | 2579 fps | 99.1% |
| Ramshot TAC | <<locked>> | 84% | 48,573 psi | 88% | 2477 fps | 99.3% |
| Ramshot Wild Boar | <<locked>> | 84% | 47,805 psi | 87% | 2490 fps | 100% |
| Ramshot X-Terminator | <<locked>> | 82% | 49,400 psi | 90% | 2461 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 35,288 psi | 64% | 1539 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 90% | 48,153 psi | 87% | 2484 fps | 98.7% |
| ReloadSwiss RS 52 | <<locked>> | 86% | 46,789 psi | 85% | 2549 fps | 99.9% |
| ReloadSwiss RS 60 | <<locked>> | 94% | 49,676 psi | 90% | 2628 fps | 100% |
| ReloadSwiss RS 62ᴾ | <<locked>> | 100% | 49,530 psi | 90% | 2615 fps | 99.9% |
| ReloadSwiss RS 70 | <<locked>> | 98% | 46,862 psi | 85% | 2592 fps | 99.5% |
| Rottweil R 901 | <<locked>> | 84% | 48,878 psi | 89% | 2428 fps | 100% |
| Rottweil R 902 | <<locked>> | 88% | 48,341 psi | 88% | 2448 fps | 100% |
| Rottweil R 903 | <<locked>> | 94% | 49,240 psi | 89% | 2520 fps | 100% |
| Rottweil R 907 | <<locked>> | 94% | 47,398 psi | 86% | 2464 fps | 97.5% |
| Shooters World Long Rifle | <<locked>> | 96% | 48,385 psi | 88% | 2487 fps | 99.2% |
| Shooters World Match Rifle | <<locked>> | 86% | 48,066 psi | 87% | 2474 fps | 100% |
| Shooters World Precision | <<locked>> | 90% | 49,240 psi | 89% | 2480 fps | 100% |
| Shooters World SW4350 | <<locked>> | 98% | 48,762 psi | 88% | 2516 fps | 98.5% |
| SNPE Vectan SP 11 | <<locked>> | 92% | 48,037 psi | 87% | 2539 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 84% | 46,557 psi | 84% | 2451 fps | 99.4% |
| SNPE Vectan SP 9 | <<locked>> | 86% | 47,703 psi | 87% | 2480 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 84% | 47,021 psi | 85% | 2356 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 92% | 49,647 psi | 90% | 2392 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 96% | 48,225 psi | 88% | 2438 fps | 98.1% |
| Somchem S321 | <<locked>> | 82% | 49,095 psi | 89% | 2487 fps | 100% |
| Somchem S335 | <<locked>> | 86% | 49,182 psi | 89% | 2395 fps | 100% |
| Somchem S341 | <<locked>> | 86% | 49,472 psi | 90% | 2490 fps | 100% |
| Somchem S355 | <<locked>> | 92% | 47,007 psi | 85% | 2480 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 44,150 psi | 80% | 2536 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 40,872 psi | 74% | 2428 fps | 96.3% |
| Vihtavuori N133 | <<locked>> | 84% | 47,268 psi | 86% | 2343 fps | 100% |
| Vihtavuori N135 | <<locked>> | 88% | 47,645 psi | 86% | 2411 fps | 100% |
| Vihtavuori N140 | <<locked>> | 88% | 48,689 psi | 88% | 2431 fps | 100% |
| Vihtavuori N150 | <<locked>> | 94% | 48,167 psi | 87% | 2457 fps | 100% |
| Vihtavuori N160 | <<locked>> | 98% | 48,892 psi | 89% | 2530 fps | 99.8% |
| Vihtavuori N530 | <<locked>> | 84% | 48,559 psi | 88% | 2451 fps | 100% |
| Vihtavuori N540 | <<locked>> | 88% | 47,036 psi | 85% | 2438 fps | 100% |
| Vihtavuori N550 | <<locked>> | 98% | 47,819 psi | 87% | 2539 fps | 99.7% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 36,680 psi | 67% | 2434 fps | 99.1% |
| Winchester 6.5 StaBALL | <<locked>> | 98% | 49,545 psi | 90% | 2513 fps | 100% |
| Winchester 748 | <<locked>> | 84% | 47,921 psi | 87% | 2493 fps | 100% |
| Winchester 760 | <<locked>> | 96% | 46,934 psi | 85% | 2549 fps | 98.2% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 30,400 psi | 55% | 2369 fps | 99.1% |
| Winchester StaBALL Match | <<locked>> | 86% | 46,905 psi | 85% | 2484 fps | 100% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 31"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2015 | <<locked>> | 80% | 44,121 psi | 80% | 2323 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 36,201 psi | 66% | 2260 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 43,294 psi | 79% | 2398 fps | 100% |
| Accurate 2700 | <<locked>> | 82% | 39,204 psi | 71% | 2283 fps | 95.2% |
| Accurate 3100 | <<locked>> | 98% | 32,430 psi | 59% | 2287 fps | 95.6% |
| Accurate 4064 | <<locked>> | 80% | 34,287 psi | 62% | 2260 fps | 100% |
| Accurate 4350 | <<locked>> | 82% | 26,411 psi | 48% | 2156 fps | 95.2% |
| ADI AR 2206H | <<locked>> | 80% | 40,495 psi | 73% | 2365 fps | 99.6% |
| ADI AR 2208 | <<locked>> | 80% | 34,505 psi | 63% | 2238 fps | 98.2% |
| ADI Benchmark 8208 | <<locked>> | 80% | 42,627 psi | 77% | 2369 fps | 100% |
| Alliant AR-Comp | <<locked>> | 80% | 42,337 psi | 77% | 2346 fps | 100% |
| Alliant Power Pro 2000-MR | 40 gr | 80% | 36,651 psi | 67% | 2402 fps | 98.8% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 33,721 psi | 61% | 2257 fps | 99.3% |
| Alliant Reloder-15 | <<locked>> | 80% | 36,318 psi | 66% | 2310 fps | 98.8% |
| Alliant Reloder-16 | <<locked>> | 82% | 28,166 psi | 51% | 2178 fps | 95.6% |
| Alliant Reloder-17 | 39.4 gr | 80% | 29,080 psi | 53% | 2238 fps | 97.9% |
| Alliant Reloder-23 | <<locked>> | 88% | 23,873 psi | 43% | 2093 fps | 95% |
| Alliant Reloder-26 | <<locked>> | 94% | 30,719 psi | 56% | 2343 fps | 96% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 39,639 psi | 72% | 2372 fps | 99% |
| Bofors RP3 | <<locked>> | 80% | 32,895 psi | 60% | 2257 fps | 99.3% |
| Bofors RP7 | <<locked>> | 88% | 39,160 psi | 71% | 2323 fps | 95.6% |
| Hodgdon Benchmark | <<locked>> | 80% | 44,788 psi | 81% | 2359 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 41,017 psi | 74% | 2395 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 80% | 45,136 psi | 82% | 2516 fps | 99.9% |
| Hodgdon H380 | <<locked>> | 80% | 33,953 psi | 62% | 2260 fps | 97.2% |
| Hodgdon H414 | <<locked>> | 88% | 35,926 psi | 65% | 2352 fps | 95.5% |
| Hodgdon H4350 | <<locked>> | 88% | 39,581 psi | 72% | 2369 fps | 95% |
| Hodgdon H4895 | <<locked>> | 80% | 40,857 psi | 74% | 2375 fps | 99.9% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 23,859 psi | 43% | 2037 fps | 95.4% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 36,782 psi | 67% | 2356 fps | 99.8% |
| Hodgdon Superformance | 46.8 gr | 90% | 38,130 psi | 69% | 2411 fps | 95.4% |
| Hodgdon TrailBoss | <<locked>> | 80% | 25,831 psi | 47% | 1339 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 39,392 psi | 71% | 2336 fps | 99.7% |
| IMR 3031 | <<locked>> | 80% | 40,350 psi | 73% | 2365 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 36,187 psi | 66% | 2264 fps | 98.8% |
| IMR 4166 Enduron | <<locked>> | 80% | 38,856 psi | 71% | 2283 fps | 96% |
| IMR 4350 | <<locked>> | 92% | 39,102 psi | 71% | 2349 fps | 95.6% |
| IMR 4451 Enduron | <<locked>> | 84% | 36,216 psi | 66% | 2264 fps | 95.2% |
| IMR 4831 | <<locked>> | 82% | 26,107 psi | 47% | 2123 fps | 95% |
| IMR 4895 | <<locked>> | 80% | 37,188 psi | 67% | 2339 fps | 99.4% |
| IMR 8208 XBR | <<locked>> | 80% | 42,627 psi | 77% | 2369 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 39,189 psi | 71% | 2346 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 41,118 psi | 75% | 2310 fps | 99.7% |
| Lovex S062 | <<locked>> | 80% | 35,853 psi | 65% | 2267 fps | 99.7% |
| Lovex S065 | <<locked>> | 82% | 31,169 psi | 57% | 2172 fps | 95.2% |
| Lovex S070 | <<locked>> | 88% | 35,447 psi | 64% | 2287 fps | 95.5% |
| Norma 201 | <<locked>> | 80% | 39,624 psi | 72% | 2320 fps | 99.9% |
| Norma 202 | <<locked>> | 80% | 39,856 psi | 72% | 2326 fps | 100% |
| Norma 203B | <<locked>> | 80% | 35,665 psi | 65% | 2300 fps | 99.1% |
| Norma 204 | <<locked>> | 96% | 44,353 psi | 80% | 2477 fps | 95.6% |
| Norma MRP | <<locked>> | 98% | 35,868 psi | 65% | 2421 fps | 95% |
| Norma URP | <<locked>> | 82% | 27,485 psi | 50% | 2162 fps | 95.3% |
| Ramshot Big Game | <<locked>> | 80% | 35,230 psi | 64% | 2316 fps | 98.9% |
| Ramshot Hunter | <<locked>> | 88% | 32,837 psi | 60% | 2293 fps | 95.3% |
| Ramshot TAC | <<locked>> | 80% | 42,583 psi | 77% | 2382 fps | 98.4% |
| Ramshot Wild Boar | <<locked>> | 80% | 41,771 psi | 76% | 2398 fps | 99.7% |
| Ramshot X-Terminator | <<locked>> | 80% | 46,253 psi | 84% | 2415 fps | 99.9% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,208 psi | 48% | 1375 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 34,650 psi | 63% | 2244 fps | 95.6% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 37,927 psi | 69% | 2405 fps | 99.2% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 31,024 psi | 56% | 2293 fps | 99.9% |
| ReloadSwiss RS 62 | <<locked>> | 84% | 28,572 psi | 52% | 2221 fps | 95.6% |
| ReloadSwiss RS 70 | <<locked>> | 86% | 31,328 psi | 57% | 2280 fps | 95.6% |
| Rottweil R 901 | <<locked>> | 80% | 43,511 psi | 79% | 2349 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 37,739 psi | 68% | 2280 fps | 99.8% |
| Rottweil R 903 | <<locked>> | 80% | 30,937 psi | 56% | 2208 fps | 98.7% |
| Rottweil R 907 | <<locked>> | 88% | 39,160 psi | 71% | 2323 fps | 95.6% |
| Shooters World Long Rifle | <<locked>> | 82% | 31,169 psi | 57% | 2172 fps | 95.2% |
| Shooters World Match Rifle | <<locked>> | 80% | 39,189 psi | 71% | 2346 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 35,853 psi | 65% | 2267 fps | 99.7% |
| Shooters World SW4350 | <<locked>> | 88% | 35,447 psi | 64% | 2287 fps | 95.5% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 32,314 psi | 59% | 2260 fps | 98.3% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 40,582 psi | 74% | 2356 fps | 98.5% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 39,262 psi | 71% | 2343 fps | 99.5% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 41,394 psi | 75% | 2274 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 34,127 psi | 62% | 2162 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 88% | 36,941 psi | 67% | 2260 fps | 95.7% |
| Somchem S321 | <<locked>> | 80% | 45,890 psi | 83% | 2441 fps | 100% |
| Somchem S335 | <<locked>> | 80% | 40,785 psi | 74% | 2277 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 40,379 psi | 73% | 2352 fps | 99.6% |
| Somchem S355 | <<locked>> | 80% | 32,068 psi | 58% | 2218 fps | 98.7% |
| Somchem S365 | <<locked>> | 80% | 22,989 psi | 42% | 2070 fps | 96.7% |
| Somchem S385 | <<locked>> | 98% | 38,363 psi | 70% | 2385 fps | 95.6% |
| Vihtavuori N133 | <<locked>> | 80% | 41,684 psi | 76% | 2267 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 36,999 psi | 67% | 2257 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 37,710 psi | 68% | 2270 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 30,414 psi | 55% | 2162 fps | 99.3% |
| Vihtavuori N160 | <<locked>> | 82% | 28,964 psi | 53% | 2165 fps | 95.8% |
| Vihtavuori N530 | <<locked>> | 80% | 42,525 psi | 77% | 2362 fps | 100% |
| Vihtavuori N540 | <<locked>> | 80% | 36,100 psi | 66% | 2267 fps | 100% |
| Vihtavuori N550 | <<locked>> | 82% | 28,152 psi | 51% | 2169 fps | 95.3% |
| Vihtavuori N555 | <<locked>> | 88% | 24,976 psi | 45% | 2156 fps | 95.1% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 27,224 psi | 49% | 2103 fps | 97.1% |
| Winchester 748 | <<locked>> | 80% | 41,930 psi | 76% | 2408 fps | 100% |
| Winchester 760 | <<locked>> | 88% | 35,926 psi | 65% | 2352 fps | 95.5% |
| Winchester StaBALL HD | <<locked>> | 92% | 23,699 psi | 43% | 2149 fps | 95.1% |
| Winchester StaBALL Match | <<locked>> | 80% | 38,435 psi | 70% | 2346 fps | 99.7% |
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 97 powders for 7.5 x 55 Swiss loaded with the .308 | 203gr | Peregrine Plainsmaster (VLR-4). Alliant Reloder-17 delivers the highest muzzle velocity at 2,628 fps; across all powders the maximum-charge window runs from 1,499 fps to 2,628 fps. Accurate 3100 gives the best case fill at 100 %, and 97 of the 97 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (380 MPa), the top charges use 55–90 %, leaving at least 10 % headroom. The 203.0 gr projectile in 0.308" calls for a 1:9.5 twist; slower twists will usually not stabilise this weight. Accurate 3100, Accurate 4350, Alliant Reloder-16 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 7.5 x 55 Swiss with the .308 | 203gr | Peregrine Plainsmaster (VLR-4) 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.