Load Specifications
Load data in caliber 7.5 x 55 Swiss with .308 | 201gr | RWS UNI Classic bullet and 94 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.
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: 31"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2495 | <<locked>> | 84% | 48,312 psi | 88% | 2477 fps | 100% |
| Accurate 2700 | <<locked>> | 84% | 47,427 psi | 86% | 2484 fps | 98% |
| Accurate 3100ᴾ | <<locked>> | 100% | 41,814 psi | 76% | 2513 fps | 98.7% |
| Accurate 4064 | <<locked>> | 86% | 48,399 psi | 88% | 2526 fps | 100% |
| Accurate 4350 | <<locked>> | 94% | 47,485 psi | 86% | 2612 fps | 100% |
| ADI AR 2206H | <<locked>> | 82% | 48,733 psi | 88% | 2552 fps | 100% |
| ADI AR 2208 | <<locked>> | 88% | 49,792 psi | 90% | 2559 fps | 100% |
| ADI AR 2209ᴾ | <<locked>> | 100% | 49,647 psi | 90% | 2648 fps | 97.8% |
| Alliant Power Pro 2000-MR | <<locked>> | 84% | 47,703 psi | 87% | 2664 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 88% | 49,719 psi | 90% | 2579 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 84% | 47,224 psi | 86% | 2552 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 96% | 49,385 psi | 90% | 2667 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 92% | 49,792 psi | 90% | 2694 fps | 100% |
| Alliant Reloder-19ᴾ | <<locked>> | 100% | 48,617 psi | 88% | 2641 fps | 97.8% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 42,250 psi | 77% | 2582 fps | 96.6% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 39,856 psi | 72% | 2539 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 35,302 psi | 64% | 2461 fps | 97.8% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 44,425 psi | 81% | 2700 fps | 99.9% |
| Baschieri & Pellagri 107 | <<locked>> | 82% | 48,138 psi | 87% | 2569 fps | 100% |
| Bofors RP3 | <<locked>> | 86% | 46,789 psi | 85% | 2546 fps | 100% |
| Bofors RP5ᴾ | <<locked>> | 100% | 42,250 psi | 77% | 2582 fps | 96.6% |
| Bofors RP7 | <<locked>> | 90% | 47,152 psi | 86% | 2523 fps | 98.2% |
| Hodgdon H380 | <<locked>> | 86% | 47,659 psi | 86% | 2559 fps | 99.8% |
| Hodgdon H414 | <<locked>> | 92% | 47,094 psi | 85% | 2615 fps | 98.9% |
| Hodgdon H4350 | <<locked>> | 90% | 47,979 psi | 87% | 2575 fps | 97.8% |
| Hodgdon H4895 | <<locked>> | 82% | 49,240 psi | 89% | 2562 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 98% | 48,602 psi | 88% | 2592 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 84% | 48,269 psi | 88% | 2592 fps | 100% |
| Hodgdon Superformance | <<locked>> | 92% | 46,992 psi | 85% | 2641 fps | 98.5% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,752 psi | 65% | 1568 fps | 100% |
| Hodgdon VARGET | <<locked>> | 82% | 47,297 psi | 86% | 2520 fps | 100% |
| IMR 3031 | <<locked>> | 82% | 49,371 psi | 90% | 2539 fps | 100% |
| IMR 4064 | <<locked>> | 86% | 49,356 psi | 90% | 2539 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 84% | 49,139 psi | 89% | 2523 fps | 98.8% |
| IMR 4350 | <<locked>> | 94% | 47,587 psi | 86% | 2556 fps | 98.3% |
| IMR 4451 Enduron | <<locked>> | 90% | 49,182 psi | 89% | 2556 fps | 98.8% |
| IMR 4831 | <<locked>> | 96% | 48,225 psi | 88% | 2605 fps | 100% |
| IMR 4895 | <<locked>> | 84% | 48,443 psi | 88% | 2579 fps | 100% |
| IMR 4955 Enduronᴾ | <<locked>> | 100% | 49,559 psi | 90% | 2585 fps | 96% |
| Lovex D073.6 | <<locked>> | 82% | 48,138 psi | 87% | 2526 fps | 100% |
| Lovex S060 | <<locked>> | 82% | 48,747 psi | 88% | 2487 fps | 100% |
| Lovex S062 | <<locked>> | 86% | 49,284 psi | 89% | 2536 fps | 100% |
| Lovex S065 | <<locked>> | 92% | 48,443 psi | 88% | 2549 fps | 99.6% |
| Lovex S070 | <<locked>> | 94% | 49,211 psi | 89% | 2585 fps | 99.1% |
| Lovex S071ᴾ | <<locked>> | 100% | 34,679 psi | 63% | 2379 fps | 97.1% |
| Norma 201 | <<locked>> | 82% | 47,877 psi | 87% | 2503 fps | 100% |
| Norma 202 | <<locked>> | 82% | 48,167 psi | 87% | 2500 fps | 100% |
| Norma 203B | <<locked>> | 86% | 49,400 psi | 90% | 2585 fps | 100% |
| Norma 204 | <<locked>> | 94% | 47,282 psi | 86% | 2595 fps | 97.2% |
| Norma MRPᴾ | <<locked>> | 100% | 44,353 psi | 80% | 2657 fps | 98.4% |
| Norma URP | <<locked>> | 94% | 47,152 psi | 86% | 2605 fps | 99.9% |
| Ramshot Big Game | <<locked>> | 86% | 49,617 psi | 90% | 2612 fps | 100% |
| Ramshot Hunter | <<locked>> | 96% | 48,965 psi | 89% | 2654 fps | 99.6% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,143 psi | 66% | 1604 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 86% | 47,921 psi | 87% | 2543 fps | 99.2% |
| ReloadSwiss RS 52 | <<locked>> | 82% | 46,934 psi | 85% | 2608 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 90% | 49,574 psi | 90% | 2687 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 94% | 47,239 psi | 86% | 2638 fps | 99.9% |
| ReloadSwiss RS 70 | <<locked>> | 94% | 46,746 psi | 85% | 2661 fps | 99.9% |
| Rottweil R 902 | <<locked>> | 84% | 48,385 psi | 88% | 2503 fps | 100% |
| Rottweil R 903 | <<locked>> | 88% | 46,992 psi | 85% | 2543 fps | 100% |
| Rottweil R 904 | <<locked>> | 98% | 48,196 psi | 87% | 2572 fps | 96.4% |
| Rottweil R 905ᴾ | <<locked>> | 100% | 47,268 psi | 86% | 2621 fps | 97.7% |
| Rottweil R 907 | <<locked>> | 90% | 47,152 psi | 86% | 2523 fps | 98.2% |
| Shooters World Long Rifle | <<locked>> | 92% | 48,443 psi | 88% | 2549 fps | 99.6% |
| Shooters World Match Rifle | <<locked>> | 82% | 48,138 psi | 87% | 2526 fps | 100% |
| Shooters World Precision | <<locked>> | 86% | 49,284 psi | 89% | 2536 fps | 100% |
| Shooters World SW4350 | <<locked>> | 94% | 49,211 psi | 89% | 2585 fps | 99.1% |
| SNPE Vectan SP 11 | <<locked>> | 88% | 48,269 psi | 88% | 2598 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 82% | 49,516 psi | 90% | 2556 fps | 99.9% |
| SNPE Vectan SP 9 | <<locked>> | 82% | 47,137 psi | 86% | 2530 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 82% | 49,211 psi | 89% | 2441 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 88% | 49,443 psi | 90% | 2444 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 92% | 48,399 psi | 88% | 2503 fps | 98.8% |
| SNPE Vectan Tubal 8000ᴾ | <<locked>> | 100% | 46,833 psi | 85% | 2618 fps | 97.6% |
| Somchem S335 | <<locked>> | 82% | 48,733 psi | 88% | 2441 fps | 100% |
| Somchem S341 | <<locked>> | 82% | 49,052 psi | 89% | 2543 fps | 100% |
| Somchem S355 | <<locked>> | 88% | 47,543 psi | 86% | 2543 fps | 100% |
| Somchem S365 | <<locked>> | 98% | 48,022 psi | 87% | 2648 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 47,732 psi | 87% | 2598 fps | 98.4% |
| Vihtavuori N133 | <<locked>> | 82% | 49,574 psi | 90% | 2425 fps | 100% |
| Vihtavuori N135 | <<locked>> | 84% | 48,124 psi | 87% | 2467 fps | 100% |
| Vihtavuori N140 | <<locked>> | 84% | 48,631 psi | 88% | 2484 fps | 100% |
| Vihtavuori N150 | <<locked>> | 90% | 48,385 psi | 88% | 2516 fps | 100% |
| Vihtavuori N160 | <<locked>> | 94% | 49,269 psi | 89% | 2595 fps | 100% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 41,423 psi | 75% | 2477 fps | 96.7% |
| Vihtavuori N540 | <<locked>> | 84% | 46,818 psi | 85% | 2484 fps | 100% |
| Vihtavuori N550 | <<locked>> | 94% | 48,428 psi | 88% | 2608 fps | 99.9% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 43,714 psi | 79% | 2605 fps | 100% |
| Winchester 6.5 StaBALL | <<locked>> | 94% | 49,284 psi | 89% | 2575 fps | 100% |
| Winchester 760 | <<locked>> | 92% | 47,384 psi | 86% | 2618 fps | 98.9% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 35,694 psi | 65% | 2575 fps | 100% |
| Winchester StaBALL Match | <<locked>> | 82% | 46,920 psi | 85% | 2536 fps | 100% |
| Winchester Supreme 780ᴾ | <<locked>> | 100% | 45,063 psi | 82% | 2543 fps | 96.8% |
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 2495 | <<locked>> | 80% | 42,612 psi | 77% | 2398 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 41,597 psi | 75% | 2388 fps | 96.8% |
| Accurate 3100 | <<locked>> | 90% | 29,718 psi | 54% | 2270 fps | 95.4% |
| Accurate 4064 | <<locked>> | 80% | 40,335 psi | 73% | 2405 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 29,559 psi | 54% | 2274 fps | 97.2% |
| ADI AR 2206H | <<locked>> | 80% | 45,963 psi | 83% | 2510 fps | 100% |
| ADI AR 2208 | <<locked>> | 80% | 38,914 psi | 71% | 2379 fps | 99.5% |
| ADI AR 2209 | <<locked>> | 94% | 41,133 psi | 75% | 2500 fps | 95.7% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 41,684 psi | 76% | 2559 fps | 99.8% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 38,783 psi | 70% | 2402 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 41,611 psi | 76% | 2461 fps | 99.8% |
| Alliant Reloder-16 | <<locked>> | 80% | 30,211 psi | 55% | 2287 fps | 97.4% |
| Alliant Reloder-17 | 44 gr | 80% | 33,344 psi | 61% | 2398 fps | 99.5% |
| Alliant Reloder-19 | <<locked>> | 92% | 37,971 psi | 69% | 2448 fps | 95% |
| Alliant Reloder-22 | <<locked>> | 96% | 37,289 psi | 68% | 2484 fps | 95% |
| Alliant Reloder-23 | <<locked>> | 82% | 23,206 psi | 42% | 2119 fps | 95.6% |
| Alliant Reloder-25 | <<locked>> | 94% | 29,515 psi | 54% | 2310 fps | 95.2% |
| Alliant Reloder-26 | <<locked>> | 86% | 27,615 psi | 50% | 2313 fps | 95.5% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 45,121 psi | 82% | 2523 fps | 99.9% |
| Bofors RP3 | <<locked>> | 80% | 38,348 psi | 70% | 2408 fps | 100% |
| Bofors RP5 | <<locked>> | 96% | 37,289 psi | 68% | 2484 fps | 95% |
| Bofors RP7 | <<locked>> | 80% | 34,751 psi | 63% | 2290 fps | 95.1% |
| Hodgdon H380 | <<locked>> | 80% | 39,218 psi | 71% | 2415 fps | 99% |
| Hodgdon H414 | <<locked>> | 82% | 33,910 psi | 62% | 2362 fps | 95.7% |
| Hodgdon H4350 | <<locked>> | 82% | 37,347 psi | 68% | 2382 fps | 95.2% |
| Hodgdon H4895 | <<locked>> | 80% | 46,369 psi | 84% | 2520 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 27,630 psi | 50% | 2192 fps | 98% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 42,206 psi | 77% | 2500 fps | 100% |
| Hodgdon Superformance | 48.9 gr | 84% | 35,723 psi | 65% | 2425 fps | 95.6% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,498 psi | 48% | 1398 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 44,280 psi | 80% | 2474 fps | 100% |
| IMR 3031 | <<locked>> | 80% | 46,282 psi | 84% | 2497 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 40,872 psi | 74% | 2405 fps | 99.8% |
| IMR 4166 Enduron | <<locked>> | 80% | 43,453 psi | 79% | 2428 fps | 97.9% |
| IMR 4350 | <<locked>> | 84% | 34,766 psi | 63% | 2320 fps | 95.1% |
| IMR 4451 Enduron | <<locked>> | 80% | 36,216 psi | 66% | 2323 fps | 96.1% |
| IMR 4831 | <<locked>> | 80% | 28,776 psi | 52% | 2238 fps | 96.9% |
| IMR 4895 | <<locked>> | 80% | 42,641 psi | 77% | 2487 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 98% | 46,441 psi | 84% | 2536 fps | 95.3% |
| Lovex D073.6 | <<locked>> | 80% | 45,295 psi | 82% | 2487 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 45,658 psi | 83% | 2441 fps | 100% |
| Lovex S062 | <<locked>> | 80% | 40,872 psi | 74% | 2405 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 33,750 psi | 61% | 2280 fps | 96.9% |
| Lovex S070 | <<locked>> | 80% | 31,836 psi | 58% | 2257 fps | 95% |
| Lovex S071 | <<locked>> | 96% | 30,458 psi | 55% | 2287 fps | 95.7% |
| Norma 201 | <<locked>> | 80% | 45,078 psi | 82% | 2461 fps | 100% |
| Norma 202 | <<locked>> | 80% | 45,295 psi | 82% | 2461 fps | 100% |
| Norma 203B | <<locked>> | 80% | 40,988 psi | 74% | 2451 fps | 99.9% |
| Norma 204 | <<locked>> | 88% | 38,972 psi | 71% | 2444 fps | 95.1% |
| Norma MRP | <<locked>> | 92% | 34,287 psi | 62% | 2448 fps | 95.5% |
| Norma URP | <<locked>> | 80% | 29,994 psi | 54% | 2274 fps | 97.1% |
| Ramshot Big Game | <<locked>> | 80% | 40,422 psi | 73% | 2464 fps | 99.9% |
| Ramshot Hunter | <<locked>> | 82% | 31,227 psi | 57% | 2306 fps | 95.6% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,948 psi | 49% | 1434 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 39,653 psi | 72% | 2402 fps | 97.8% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 43,772 psi | 79% | 2556 fps | 99.9% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 35,505 psi | 64% | 2448 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 29,341 psi | 53% | 2290 fps | 96.7% |
| ReloadSwiss RS 70 | 44.7 gr | 80% | 29,443 psi | 53% | 2290 fps | 95.7% |
| Rottweil R 902 | <<locked>> | 80% | 42,902 psi | 78% | 2418 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 36,187 psi | 66% | 2359 fps | 99.8% |
| Rottweil R 904 | <<locked>> | 96% | 45,339 psi | 82% | 2526 fps | 95.7% |
| Rottweil R 905 | <<locked>> | 94% | 38,754 psi | 70% | 2470 fps | 95.6% |
| Rottweil R 907 | <<locked>> | 80% | 34,751 psi | 63% | 2290 fps | 95.1% |
| Shooters World Long Rifle | <<locked>> | 80% | 33,750 psi | 61% | 2280 fps | 96.9% |
| Shooters World Match Rifle | <<locked>> | 80% | 45,295 psi | 82% | 2487 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 40,872 psi | 74% | 2405 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 31,836 psi | 58% | 2257 fps | 95% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 36,970 psi | 67% | 2408 fps | 99.6% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 46,079 psi | 84% | 2503 fps | 99.7% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 44,179 psi | 80% | 2484 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 46,296 psi | 84% | 2398 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 38,595 psi | 70% | 2287 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 32,750 psi | 59% | 2224 fps | 95.2% |
| SNPE Vectan Tubal 8000 | <<locked>> | 94% | 38,421 psi | 70% | 2467 fps | 95.5% |
| Somchem S335 | <<locked>> | 80% | 45,948 psi | 83% | 2402 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 45,948 psi | 83% | 2497 fps | 100% |
| Somchem S355 | <<locked>> | 80% | 37,086 psi | 67% | 2365 fps | 99.8% |
| Somchem S365 | <<locked>> | 80% | 26,832 psi | 49% | 2234 fps | 99% |
| Somchem S385 | <<locked>> | 90% | 34,519 psi | 63% | 2362 fps | 95.2% |
| Vihtavuori N133 | <<locked>> | 80% | 46,630 psi | 85% | 2385 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 42,438 psi | 77% | 2385 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 42,859 psi | 78% | 2398 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 35,128 psi | 64% | 2300 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 31,357 psi | 57% | 2270 fps | 97.4% |
| Vihtavuori N165 | <<locked>> | 96% | 36,492 psi | 66% | 2385 fps | 95.2% |
| Vihtavuori N540 | <<locked>> | 80% | 41,278 psi | 75% | 2402 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 30,821 psi | 56% | 2277 fps | 97.1% |
| Vihtavuori N555 | <<locked>> | 82% | 24,598 psi | 45% | 2185 fps | 95.7% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 31,140 psi | 56% | 2251 fps | 99.1% |
| Winchester 760 | <<locked>> | 82% | 34,098 psi | 62% | 2365 fps | 95.8% |
| Winchester StaBALL HD | <<locked>> | 86% | 23,032 psi | 42% | 2185 fps | 96% |
| Winchester StaBALL Match | <<locked>> | 80% | 43,947 psi | 80% | 2490 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 96% | 39,291 psi | 71% | 2441 fps | 95.3% |
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 108 powders for 7.5 x 55 Swiss loaded with the .308 | 201gr | RWS UNI Classic. Alliant Reloder-26 delivers the highest muzzle velocity at 2,700 fps; across all powders the maximum-charge window runs from 1,568 fps to 2,700 fps. Accurate 3100 gives the best case fill at 100 %, and 108 of the 108 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (380 MPa), the top charges use 62–90 %, leaving at least 10 % headroom. The 201.0 gr projectile in 0.308" calls for a 1:12.5 twist; slower twists will usually not stabilise this weight. Accurate 3100, Accurate MAGPRO, ADI AR 2209 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 7.5 x 55 Swiss with the .308 | 201gr | RWS UNI Classic they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, Accurate MAGPRO, ADI AR 2213, Hodgdon H1000 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.