Load Specifications
Bullet Manufacturer:Peregrine
Bullet Weight:65 gr
Bullet Diameter:0.224"
Bullet Length:<<locked>>
Caliber:.223 WSSM load data
Case Length (l3):1.663"
Cartridge Length (C.O.L.):<<locked>>
Case Capacity:53.7 Grains of Water
Primer Size:Large Rifle (LR)
Barrel Length:24"
Max. allowed Pressure:63,817 psi
Recommended Twist Rate:1:7.0
Load data in caliber .223 WSSM with .224 | 65gr | Peregrine Glider GRM bullet and 94 powders. The key underlying parameters are shown in the table above.
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>> | 82% | 55,796 psi | 87% | 3330 fps | 100% |
| Accurate 2495 | <<locked>> | 86% | 55,027 psi | 86% | 3346 fps | 100% |
| Accurate 2520 | <<locked>> | 82% | 57,072 psi | 89% | 3428 fps | 100% |
| Accurate 2700 | <<locked>> | 86% | 54,259 psi | 85% | 3346 fps | 96.6% |
| Accurate 3100ᴾ | <<locked>> | 100% | 46,992 psi | 74% | 3278 fps | 96.8% |
| Accurate 4064 | <<locked>> | 88% | 55,434 psi | 87% | 3406 fps | 100% |
| Accurate 4350 | <<locked>> | 96% | 56,840 psi | 89% | 3507 fps | 99.6% |
| ADI AR 2206H | <<locked>> | 84% | 55,593 psi | 87% | 3445 fps | 99.9% |
| ADI AR 2208 | <<locked>> | 90% | 56,782 psi | 89% | 3445 fps | 99.8% |
| ADI Benchmark 8208 | <<locked>> | 82% | 54,404 psi | 85% | 3389 fps | 100% |
| Alliant AR-Comp | <<locked>> | 82% | 55,347 psi | 87% | 3363 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 86% | 56,202 psi | 88% | 3583 fps | 99.8% |
| Alliant Reloder- TS 15.5 | <<locked>> | 90% | 57,043 psi | 89% | 3468 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 88% | 57,638 psi | 90% | 3497 fps | 99.9% |
| Alliant Reloder-16 | <<locked>> | 98% | 57,580 psi | 90% | 3576 fps | 99.9% |
| Alliant Reloder-17 | <<locked>> | 92% | 55,405 psi | 87% | 3547 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 44,338 psi | 69% | 3314 fps | 99.3% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 50,865 psi | 80% | 3520 fps | 99% |
| Baschieri & Pellagri 107 | <<locked>> | 84% | 55,782 psi | 87% | 3455 fps | 99.6% |
| Bofors RP3 | <<locked>> | 88% | 54,128 psi | 85% | 3419 fps | 100% |
| Bofors RP7 | <<locked>> | 92% | 54,375 psi | 85% | 3392 fps | 96.8% |
| Hodgdon Benchmark | <<locked>> | 82% | 55,724 psi | 87% | 3373 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 82% | 54,041 psi | 85% | 3412 fps | 100% |
| Hodgdon H380 | <<locked>> | 88% | 55,172 psi | 86% | 3442 fps | 99.1% |
| Hodgdon H414 | <<locked>> | 94% | 55,767 psi | 87% | 3497 fps | 97.7% |
| Hodgdon H4350 | <<locked>> | 92% | 55,753 psi | 87% | 3455 fps | 96.4% |
| Hodgdon H4895 | <<locked>> | 84% | 56,188 psi | 88% | 3458 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 98% | 53,998 psi | 85% | 3422 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 86% | 56,159 psi | 88% | 3491 fps | 100% |
| Hodgdon Superformance | <<locked>> | 94% | 56,420 psi | 88% | 3533 fps | 97.6% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,476 psi | 56% | 2201 fps | 100% |
| Hodgdon VARGET | <<locked>> | 86% | 57,624 psi | 90% | 3465 fps | 100% |
| IMR 3031 | <<locked>> | 84% | 56,434 psi | 88% | 3445 fps | 100% |
| IMR 4064 | <<locked>> | 88% | 56,101 psi | 88% | 3425 fps | 99.8% |
| IMR 4166 Enduron | <<locked>> | 86% | 55,912 psi | 88% | 3402 fps | 97.6% |
| IMR 4350 | <<locked>> | 96% | 55,013 psi | 86% | 3419 fps | 97% |
| IMR 4451 Enduron | <<locked>> | 92% | 56,014 psi | 88% | 3425 fps | 97.6% |
| IMR 4831 | <<locked>> | 98% | 57,276 psi | 90% | 3494 fps | 99.7% |
| IMR 4895 | <<locked>> | 86% | 55,419 psi | 87% | 3468 fps | 99.9% |
| IMR 8208 XBR | <<locked>> | 82% | 54,404 psi | 85% | 3389 fps | 100% |
| Lovex D073.6 | <<locked>> | 84% | 55,419 psi | 87% | 3409 fps | 100% |
| Lovex S060 | <<locked>> | 84% | 54,505 psi | 85% | 3363 fps | 99.9% |
| Lovex S062 | <<locked>> | 88% | 56,043 psi | 88% | 3422 fps | 100% |
| Lovex S065 | <<locked>> | 94% | 55,666 psi | 87% | 3419 fps | 98.7% |
| Lovex S070 | <<locked>> | 96% | 57,058 psi | 89% | 3461 fps | 98.1% |
| Norma 201 | <<locked>> | 86% | 57,435 psi | 90% | 3438 fps | 100% |
| Norma 202 | <<locked>> | 84% | 54,592 psi | 86% | 3383 fps | 100% |
| Norma 203B | <<locked>> | 88% | 56,826 psi | 89% | 3478 fps | 99.9% |
| Norma 204 | <<locked>> | 96% | 56,101 psi | 88% | 3474 fps | 95.9% |
| Norma MRPᴾ | <<locked>> | 100% | 50,256 psi | 79% | 3468 fps | 96.5% |
| Norma URP | <<locked>> | 96% | 55,579 psi | 87% | 3491 fps | 99.5% |
| Ramshot Big Game | <<locked>> | 86% | 54,317 psi | 85% | 3442 fps | 99.8% |
| Ramshot Hunter | <<locked>> | 96% | 54,549 psi | 85% | 3478 fps | 98.3% |
| Ramshot TAC | <<locked>> | 82% | 54,665 psi | 86% | 3399 fps | 98.7% |
| Ramshot Wild Boar | <<locked>> | 82% | 54,404 psi | 85% | 3419 fps | 99.8% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 35,984 psi | 56% | 2251 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 88% | 55,230 psi | 87% | 3415 fps | 98.1% |
| ReloadSwiss RS 52 | <<locked>> | 84% | 54,578 psi | 86% | 3507 fps | 99.6% |
| ReloadSwiss RS 60 | <<locked>> | 90% | 54,781 psi | 86% | 3547 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 96% | 56,956 psi | 89% | 3527 fps | 99.5% |
| ReloadSwiss RS 70 | <<locked>> | 96% | 55,796 psi | 87% | 3556 fps | 99.3% |
| Rottweil R 901 | <<locked>> | 82% | 54,636 psi | 86% | 3366 fps | 100% |
| Rottweil R 902 | <<locked>> | 86% | 54,708 psi | 86% | 3383 fps | 100% |
| Rottweil R 903 | <<locked>> | 90% | 54,360 psi | 85% | 3419 fps | 100% |
| Rottweil R 907 | <<locked>> | 92% | 54,375 psi | 85% | 3392 fps | 96.8% |
| Shooters World Long Rifle | <<locked>> | 94% | 55,666 psi | 87% | 3419 fps | 98.7% |
| Shooters World Match Rifle | <<locked>> | 84% | 55,419 psi | 87% | 3409 fps | 100% |
| Shooters World Precision | <<locked>> | 88% | 56,043 psi | 88% | 3422 fps | 100% |
| Shooters World SW4350 | <<locked>> | 96% | 57,058 psi | 89% | 3461 fps | 98.1% |
| SNPE Vectan SP 11 | <<locked>> | 90% | 56,492 psi | 89% | 3488 fps | 99.9% |
| SNPE Vectan SP 7 | <<locked>> | 84% | 57,130 psi | 90% | 3442 fps | 99.3% |
| SNPE Vectan SP 9 | <<locked>> | 84% | 53,969 psi | 85% | 3402 fps | 99.8% |
| SNPE Vectan Tubal 3000 | <<locked>> | 84% | 55,288 psi | 87% | 3320 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 90% | 56,188 psi | 88% | 3314 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 94% | 55,811 psi | 87% | 3360 fps | 97.7% |
| Somchem S335 | <<locked>> | 84% | 54,636 psi | 86% | 3307 fps | 100% |
| Somchem S341 | <<locked>> | 84% | 56,768 psi | 89% | 3432 fps | 99.9% |
| Somchem S355 | <<locked>> | 90% | 54,346 psi | 85% | 3412 fps | 99.9% |
| Somchem S365 | <<locked>> | 98% | 54,085 psi | 85% | 3488 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 53,461 psi | 84% | 3409 fps | 96.7% |
| Vihtavuori N133 | <<locked>> | 84% | 55,724 psi | 87% | 3301 fps | 100% |
| Vihtavuori N135 | <<locked>> | 86% | 54,447 psi | 85% | 3340 fps | 100% |
| Vihtavuori N140 | <<locked>> | 86% | 55,651 psi | 87% | 3363 fps | 100% |
| Vihtavuori N150 | <<locked>> | 92% | 56,159 psi | 88% | 3392 fps | 100% |
| Vihtavuori N160 | <<locked>> | 94% | 54,418 psi | 85% | 3425 fps | 99.3% |
| Vihtavuori N530 | <<locked>> | 82% | 54,839 psi | 86% | 3386 fps | 100% |
| Vihtavuori N540 | <<locked>> | 88% | 57,508 psi | 90% | 3409 fps | 100% |
| Vihtavuori N550 | <<locked>> | 96% | 57,043 psi | 89% | 3488 fps | 99.5% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 49,414 psi | 77% | 3406 fps | 99.2% |
| Winchester 6.5 StaBALL | <<locked>> | 94% | 54,447 psi | 85% | 3389 fps | 100% |
| Winchester 748 | <<locked>> | 82% | 55,143 psi | 86% | 3438 fps | 100% |
| Winchester 760 | <<locked>> | 94% | 55,767 psi | 87% | 3497 fps | 97.7% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 39,958 psi | 63% | 3327 fps | 99.5% |
| Winchester StaBALL Match | <<locked>> | 84% | 54,288 psi | 85% | 3415 fps | 100% |
Start Load - Barrel Length: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2015 | <<locked>> | 80% | 52,243 psi | 82% | 3271 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 44,788 psi | 70% | 3173 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 53,040 psi | 83% | 3363 fps | 100% |
| Accurate 2700 | <<locked>> | 84% | 50,517 psi | 79% | 3274 fps | 95.7% |
| Accurate 3100 | <<locked>> | 98% | 43,772 psi | 69% | 3212 fps | 95.9% |
| Accurate 4064 | <<locked>> | 80% | 42,424 psi | 66% | 3163 fps | 100% |
| Accurate 4350 | <<locked>> | 84% | 36,738 psi | 58% | 3081 fps | 95.4% |
| ADI AR 2206H | <<locked>> | 80% | 48,530 psi | 76% | 3314 fps | 99.3% |
| ADI AR 2208 | <<locked>> | 80% | 41,379 psi | 65% | 3130 fps | 97.5% |
| ADI Benchmark 8208 | <<locked>> | 80% | 50,662 psi | 79% | 3320 fps | 99.9% |
| Alliant AR-Comp | <<locked>> | 80% | 51,634 psi | 81% | 3307 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 44,904 psi | 70% | 3350 fps | 98.3% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 41,046 psi | 64% | 3150 fps | 98.7% |
| Alliant Reloder-15 | <<locked>> | 80% | 44,063 psi | 69% | 3228 fps | 98.2% |
| Alliant Reloder-16 | <<locked>> | 84% | 36,434 psi | 57% | 3100 fps | 95.4% |
| Alliant Reloder-17 | <<locked>> | 80% | 35,810 psi | 56% | 3107 fps | 97.1% |
| Alliant Reloder-23 | <<locked>> | 90% | 31,720 psi | 50% | 2969 fps | 95.2% |
| Alliant Reloder-26 | <<locked>> | 92% | 37,579 psi | 59% | 3196 fps | 95.2% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 48,385 psi | 76% | 3314 fps | 98.6% |
| Bofors RP3 | <<locked>> | 80% | 40,959 psi | 64% | 3153 fps | 98.8% |
| Bofors RP7 | <<locked>> | 88% | 47,761 psi | 75% | 3261 fps | 95.2% |
| Hodgdon Benchmark | <<locked>> | 80% | 52,315 psi | 82% | 3314 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 50,299 psi | 79% | 3346 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 41,698 psi | 65% | 3159 fps | 96.5% |
| Hodgdon H414 | <<locked>> | 88% | 45,353 psi | 71% | 3287 fps | 95.2% |
| Hodgdon H4350 | <<locked>> | 90% | 52,272 psi | 82% | 3389 fps | 95.6% |
| Hodgdon H4895 | <<locked>> | 80% | 49,023 psi | 77% | 3327 fps | 99.6% |
| Hodgdon Hybrid 100V | <<locked>> | 82% | 31,198 psi | 49% | 2900 fps | 95.1% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 45,745 psi | 72% | 3294 fps | 99.5% |
| Hodgdon Superformance | <<locked>> | 90% | 48,588 psi | 76% | 3379 fps | 95.7% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,295 psi | 41% | 1972 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 47,094 psi | 74% | 3268 fps | 99.4% |
| IMR 3031 | <<locked>> | 80% | 49,211 psi | 77% | 3323 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 43,468 psi | 68% | 3176 fps | 98.2% |
| IMR 4166 Enduron | <<locked>> | 80% | 45,876 psi | 72% | 3199 fps | 95.3% |
| IMR 4350 | <<locked>> | 92% | 48,399 psi | 76% | 3287 fps | 95.4% |
| IMR 4451 Enduron | <<locked>> | 86% | 46,354 psi | 73% | 3232 fps | 95.3% |
| IMR 4831 | <<locked>> | 86% | 37,884 psi | 59% | 3094 fps | 95.9% |
| IMR 4895 | <<locked>> | 80% | 45,208 psi | 71% | 3268 fps | 98.9% |
| IMR 8208 XBR | <<locked>> | 80% | 50,662 psi | 79% | 3320 fps | 99.9% |
| Lovex D073.6 | <<locked>> | 80% | 48,501 psi | 76% | 3291 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 48,008 psi | 75% | 3235 fps | 99.3% |
| Lovex S062 | <<locked>> | 80% | 43,134 psi | 68% | 3173 fps | 99.3% |
| Lovex S065 | <<locked>> | 84% | 40,350 psi | 63% | 3097 fps | 95.1% |
| Lovex S070 | <<locked>> | 88% | 44,063 psi | 69% | 3202 fps | 95.1% |
| Norma 201 | <<locked>> | 80% | 47,253 psi | 74% | 3251 fps | 99.7% |
| Norma 202 | <<locked>> | 80% | 47,877 psi | 75% | 3261 fps | 100% |
| Norma 203B | <<locked>> | 80% | 43,453 psi | 68% | 3215 fps | 98.5% |
| Norma 204 | <<locked>> | 94% | 52,431 psi | 82% | 3406 fps | 95% |
| Norma MRP | <<locked>> | 98% | 46,586 psi | 73% | 3386 fps | 95.4% |
| Norma URP | <<locked>> | 84% | 36,970 psi | 58% | 3087 fps | 95.3% |
| Ramshot Big Game | <<locked>> | 80% | 43,627 psi | 68% | 3232 fps | 98.5% |
| Ramshot Hunter | <<locked>> | 90% | 44,411 psi | 70% | 3271 fps | 96% |
| Ramshot TAC | <<locked>> | 80% | 50,995 psi | 80% | 3330 fps | 98.1% |
| Ramshot Wild Boar | <<locked>> | 80% | 51,053 psi | 80% | 3356 fps | 99.6% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,818 psi | 42% | 2024 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 82% | 45,281 psi | 71% | 3212 fps | 95.8% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 47,224 psi | 74% | 3360 fps | 98.7% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 38,174 psi | 60% | 3192 fps | 99.6% |
| ReloadSwiss RS 62 | <<locked>> | 86% | 39,552 psi | 62% | 3169 fps | 96% |
| ReloadSwiss RS 70 | <<locked>> | 86% | 39,117 psi | 61% | 3179 fps | 95.2% |
| Rottweil R 901 | <<locked>> | 80% | 51,227 psi | 80% | 3304 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 44,962 psi | 70% | 3196 fps | 99.5% |
| Rottweil R 903 | <<locked>> | 80% | 38,392 psi | 60% | 3084 fps | 98% |
| Rottweil R 907 | <<locked>> | 88% | 47,761 psi | 75% | 3261 fps | 95.2% |
| Shooters World Long Rifle | <<locked>> | 84% | 40,350 psi | 63% | 3097 fps | 95.1% |
| Shooters World Match Rifle | <<locked>> | 80% | 48,501 psi | 76% | 3291 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 43,134 psi | 68% | 3173 fps | 99.3% |
| Shooters World SW4350 | <<locked>> | 88% | 44,063 psi | 69% | 3202 fps | 95.1% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 39,784 psi | 62% | 3146 fps | 97.6% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 49,443 psi | 77% | 3301 fps | 98.2% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 47,181 psi | 74% | 3271 fps | 99.1% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 48,762 psi | 76% | 3209 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 40,843 psi | 64% | 3038 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 88% | 45,701 psi | 72% | 3166 fps | 95.4% |
| Somchem S335 | <<locked>> | 80% | 48,153 psi | 75% | 3196 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 49,197 psi | 77% | 3291 fps | 99.4% |
| Somchem S355 | <<locked>> | 80% | 39,059 psi | 61% | 3091 fps | 97.9% |
| Somchem S365 | <<locked>> | 80% | 28,514 psi | 45% | 2874 fps | 95.3% |
| Somchem S385 | <<locked>> | 98% | 49,980 psi | 78% | 3343 fps | 95.8% |
| Vihtavuori N133 | <<locked>> | 80% | 49,240 psi | 77% | 3196 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 45,092 psi | 71% | 3179 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 45,411 psi | 71% | 3182 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 37,289 psi | 58% | 3015 fps | 98.7% |
| Vihtavuori N160 | <<locked>> | 84% | 38,537 psi | 60% | 3091 fps | 95.9% |
| Vihtavuori N530 | <<locked>> | 80% | 50,952 psi | 80% | 3320 fps | 100% |
| Vihtavuori N540 | <<locked>> | 80% | 43,888 psi | 69% | 3163 fps | 100% |
| Vihtavuori N550 | <<locked>> | 84% | 37,898 psi | 59% | 3084 fps | 95.4% |
| Vihtavuori N555 | <<locked>> | 90% | 34,795 psi | 55% | 3064 fps | 95.3% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 33,170 psi | 52% | 2920 fps | 96.4% |
| Winchester 748 | <<locked>> | 80% | 51,619 psi | 81% | 3376 fps | 100% |
| Winchester 760 | <<locked>> | 88% | 45,353 psi | 71% | 3287 fps | 95.2% |
| Winchester StaBALL HD | <<locked>> | 94% | 32,430 psi | 51% | 3081 fps | 96.5% |
| Winchester StaBALL Match | <<locked>> | 80% | 46,963 psi | 74% | 3274 fps | 99.5% |
ᴾ possible press load - work up slowly to this load while watching for signs of excessive pressure.
This overview compares 114 powders for .223 WSSM loaded with the .224 | 65gr | Peregrine Glider GRM. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 3,583 fps; across all powders the maximum-charge window runs from 2,201 fps to 3,583 fps. Accurate 3100 gives the best case fill at 100 %, and 114 of the 114 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (440 MPa), the top charges use 56–90 %, leaving at least 10 % headroom. The 65.0 gr projectile in 0.224" calls for a 1:7.0 twist; slower twists will usually not stabilise this weight. Accurate 3100, Accurate High Country, 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. As outliers, Accurate High Country, ADI AR 2213, Alliant Reloder-22 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.