Load Specifications
Bullet:.375 | 300gr | Speer TBBC
Bullet Manufacturer:Speer
Bullet Weight:300 gr
Bullet Diameter:0.375"
Bullet Length:<<locked>>
Caliber:.375 H&H Mag. load data
Case Length (l3):2.859"
Cartridge Length (C.O.L.):<<locked>>
Case Capacity:95.3 Grains of Water
Primer Size:Large Rifle Magnum (LRM)
Barrel Length:24"
Max. allowed Pressure:62,366 psi
Recommended Twist Rate:1:6.0
Load data in caliber .375 H&H Mag. with .375 | 300gr | Speer TBBC bullet and 108 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, ReloadSwiss RS 60 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>> | 88% | 56,304 psi | 90% | 2375 fps | 100% |
| Accurate 2460 | <<locked>> | 84% | 54,940 psi | 88% | 2405 fps | 100% |
| Accurate 2495 | <<locked>> | 92% | 54,027 psi | 87% | 2398 fps | 100% |
| Accurate 2520 | <<locked>> | 88% | 54,781 psi | 88% | 2451 fps | 100% |
| Accurate 2520 | <<locked>> | 88% | 54,781 psi | 88% | 2451 fps | 100% |
| Accurate 2700 | <<locked>> | 96% | 55,201 psi | 89% | 2402 fps | 96.6% |
| Accurate 4064 | <<locked>> | 94% | 53,911 psi | 86% | 2438 fps | 100% |
| Accurate 4350ᴾ | <<locked>> | 100% | 49,284 psi | 79% | 2454 fps | 99% |
| Accurate LT-30 | <<locked>> | 82% | 55,651 psi | 89% | 2326 fps | 100% |
| Accurate LT-32 | <<locked>> | 82% | 56,086 psi | 90% | 2349 fps | 100% |
| ADI AR 2206H | <<locked>> | 90% | 55,303 psi | 89% | 2467 fps | 99.9% |
| ADI AR 2208 | <<locked>> | 96% | 56,101 psi | 90% | 2464 fps | 99.8% |
| ADI Benchmark 8208 | <<locked>> | 88% | 54,549 psi | 87% | 2425 fps | 100% |
| Alliant AR-Comp | <<locked>> | 88% | 54,737 psi | 88% | 2402 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 84% | 56,347 psi | 90% | 2516 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 92% | 54,636 psi | 88% | 2569 fps | 99.8% |
| Alliant Reloder- TS 15.5 | <<locked>> | 96% | 55,637 psi | 89% | 2484 fps | 100% |
| Alliant Reloder-10x | <<locked>> | 84% | 56,188 psi | 90% | 2379 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 92% | 53,084 psi | 85% | 2461 fps | 99.7% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 48,559 psi | 78% | 2461 fps | 99.1% |
| Alliant Reloder-17ᴾ | <<locked>> | 100% | 56,130 psi | 90% | 2592 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 34,389 psi | 55% | 2231 fps | 97.2% |
| Baschieri & Pellagri 106 | <<locked>> | 82% | 54,810 psi | 88% | 2329 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 90% | 54,940 psi | 88% | 2484 fps | 99.6% |
| Bofors RP3 | <<locked>> | 96% | 56,101 psi | 90% | 2497 fps | 100% |
| Bofors RP7 | <<locked>> | 98% | 53,214 psi | 85% | 2421 fps | 96.6% |
| Hodgdon Benchmark | <<locked>> | 86% | 53,345 psi | 86% | 2369 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 88% | 53,301 psi | 85% | 2454 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 86% | 55,201 psi | 89% | 2539 fps | 99.8% |
| Hodgdon H322 | <<locked>> | 86% | 54,665 psi | 88% | 2411 fps | 100% |
| Hodgdon H335 | <<locked>> | 82% | 55,999 psi | 90% | 2444 fps | 100% |
| Hodgdon H380 | <<locked>> | 94% | 53,853 psi | 86% | 2464 fps | 99.1% |
| Hodgdon H414 | <<locked>> | 98% | 54,331 psi | 87% | 2523 fps | 97.6% |
| Hodgdon H4350ᴾ | <<locked>> | 100% | 52,083 psi | 84% | 2441 fps | 95.7% |
| Hodgdon H4895 | <<locked>> | 90% | 55,796 psi | 89% | 2477 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 44,599 psi | 72% | 2356 fps | 99.4% |
| Hodgdon LEVERevolution | <<locked>> | 94% | 54,404 psi | 87% | 2503 fps | 100% |
| Hodgdon Superformanceᴾ | <<locked>> | 100% | 53,940 psi | 86% | 2533 fps | 96.9% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,027 psi | 56% | 1447 fps | 100% |
| Hodgdon VARGET | <<locked>> | 94% | 55,970 psi | 90% | 2464 fps | 100% |
| IMR 3031 | <<locked>> | 92% | 53,650 psi | 86% | 2438 fps | 100% |
| IMR 4064 | <<locked>> | 96% | 54,795 psi | 88% | 2438 fps | 99.8% |
| IMR 4166 Enduron | <<locked>> | 96% | 54,708 psi | 88% | 2415 fps | 97.5% |
| IMR 4198 | <<locked>> | 82% | 53,272 psi | 85% | 2303 fps | 100% |
| IMR 4350ᴾ | <<locked>> | 100% | 49,835 psi | 80% | 2395 fps | 96% |
| IMR 4451 Enduron | <<locked>> | 98% | 55,390 psi | 89% | 2454 fps | 97.5% |
| IMR 4831ᴾ | <<locked>> | 100% | 41,698 psi | 67% | 2323 fps | 97.8% |
| IMR 4895 | <<locked>> | 92% | 54,389 psi | 87% | 2487 fps | 99.9% |
| IMR 8208 XBR | <<locked>> | 88% | 54,549 psi | 87% | 2425 fps | 100% |
| Lovex D073.4 | <<locked>> | 82% | 53,403 psi | 86% | 2388 fps | 100% |
| Lovex D073.5 | <<locked>> | 84% | 54,679 psi | 88% | 2415 fps | 100% |
| Lovex D073.6 | <<locked>> | 90% | 54,549 psi | 87% | 2448 fps | 100% |
| Lovex S060 | <<locked>> | 90% | 55,361 psi | 89% | 2405 fps | 99.9% |
| Lovex S062 | <<locked>> | 94% | 55,172 psi | 88% | 2444 fps | 100% |
| Lovex S065ᴾ | <<locked>> | 100% | 54,215 psi | 87% | 2444 fps | 98.6% |
| Lovex S070ᴾ | <<locked>> | 100% | 51,416 psi | 82% | 2425 fps | 97.2% |
| Norma 201 | <<locked>> | 90% | 53,998 psi | 87% | 2418 fps | 100% |
| Norma 202 | <<locked>> | 90% | 54,520 psi | 87% | 2421 fps | 100% |
| Norma 203B | <<locked>> | 94% | 55,608 psi | 89% | 2493 fps | 100% |
| Norma URPᴾ | <<locked>> | 100% | 48,849 psi | 78% | 2448 fps | 98.9% |
| Ramshot Big Game | <<locked>> | 94% | 56,101 psi | 90% | 2516 fps | 99.9% |
| Ramshot Hunterᴾ | <<locked>> | 100% | 48,153 psi | 77% | 2441 fps | 97.2% |
| Ramshot TAC | <<locked>> | 88% | 54,853 psi | 88% | 2444 fps | 98.8% |
| Ramshot Wild Boar | <<locked>> | 88% | 54,143 psi | 87% | 2461 fps | 99.9% |
| Ramshot X-Terminator | <<locked>> | 86% | 55,796 psi | 89% | 2431 fps | 99.9% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 35,505 psi | 57% | 1483 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 84% | 54,302 psi | 87% | 2411 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 94% | 54,375 psi | 87% | 2448 fps | 98% |
| ReloadSwiss RS 52 | <<locked>> | 90% | 53,127 psi | 85% | 2516 fps | 99.7% |
| ReloadSwiss RS 60 | <<locked>> | 98% | 55,941 psi | 90% | 2592 fps | 100% |
| ReloadSwiss RS 62ᴾ | <<locked>> | 100% | 48,762 psi | 78% | 2474 fps | 98.7% |
| ReloadSwiss RS 70ᴾ | <<locked>> | 100% | 49,516 psi | 79% | 2493 fps | 98.4% |
| Rottweil R 901 | <<locked>> | 88% | 55,129 psi | 88% | 2402 fps | 100% |
| Rottweil R 902 | <<locked>> | 92% | 54,447 psi | 87% | 2418 fps | 100% |
| Rottweil R 903 | <<locked>> | 98% | 55,956 psi | 90% | 2490 fps | 100% |
| Rottweil R 907 | <<locked>> | 98% | 53,214 psi | 85% | 2421 fps | 96.6% |
| Shooters World Long Rifleᴾ | <<locked>> | 100% | 54,215 psi | 87% | 2444 fps | 98.6% |
| Shooters World Match Rifle | <<locked>> | 90% | 54,549 psi | 87% | 2448 fps | 100% |
| Shooters World Precision | <<locked>> | 94% | 55,172 psi | 88% | 2444 fps | 100% |
| Shooters World SW4350ᴾ | <<locked>> | 100% | 51,416 psi | 82% | 2425 fps | 97.2% |
| Shooters World Tactical Rifle | <<locked>> | 82% | 53,998 psi | 87% | 2385 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 96% | 54,157 psi | 87% | 2500 fps | 99.9% |
| SNPE Vectan SP 3 | <<locked>> | 82% | 53,795 psi | 86% | 2359 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 88% | 53,069 psi | 85% | 2425 fps | 98.9% |
| SNPE Vectan SP 9 | <<locked>> | 90% | 53,780 psi | 86% | 2448 fps | 99.9% |
| SNPE Vectan Tubal 3000 | <<locked>> | 90% | 56,115 psi | 90% | 2369 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 96% | 55,883 psi | 90% | 2365 fps | 100% |
| SNPE Vectan Tubal 7000ᴾ | <<locked>> | 100% | 54,708 psi | 88% | 2402 fps | 97.4% |
| Somchem S321 | <<locked>> | 86% | 55,796 psi | 89% | 2461 fps | 100% |
| Somchem S335 | <<locked>> | 90% | 55,042 psi | 88% | 2365 fps | 100% |
| Somchem S341 | <<locked>> | 90% | 56,188 psi | 90% | 2464 fps | 99.9% |
| Somchem S355 | <<locked>> | 98% | 56,318 psi | 90% | 2484 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 43,584 psi | 70% | 2405 fps | 99.9% |
| Unknown powderᴾ | <<locked>> | 100% | 53,650 psi | 86% | 2503 fps | 99% |
| Vihtavuori N130 | <<locked>> | 86% | 56,072 psi | 90% | 2336 fps | 100% |
| Vihtavuori N133 | <<locked>> | 90% | 56,115 psi | 90% | 2352 fps | 100% |
| Vihtavuori N135 | <<locked>> | 92% | 53,766 psi | 86% | 2385 fps | 100% |
| Vihtavuori N140 | <<locked>> | 92% | 54,911 psi | 88% | 2402 fps | 100% |
| Vihtavuori N150 | <<locked>> | 98% | 54,534 psi | 87% | 2428 fps | 100% |
| Vihtavuori N160ᴾ | <<locked>> | 100% | 51,590 psi | 83% | 2448 fps | 99.1% |
| Vihtavuori N530 | <<locked>> | 88% | 55,143 psi | 88% | 2428 fps | 100% |
| Vihtavuori N540 | <<locked>> | 94% | 56,362 psi | 90% | 2444 fps | 100% |
| Vihtavuori N550ᴾ | <<locked>> | 100% | 50,502 psi | 81% | 2451 fps | 98.9% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 36,506 psi | 59% | 2293 fps | 97.1% |
| Winchester 6.5 StaBALLᴾ | <<locked>> | 100% | 52,373 psi | 84% | 2434 fps | 100% |
| Winchester 748 | <<locked>> | 86% | 55,274 psi | 89% | 2477 fps | 100% |
| Winchester 760 | <<locked>> | 98% | 54,331 psi | 87% | 2523 fps | 97.6% |
| Winchester StaBALL Match | <<locked>> | 84% | 54,955 psi | 88% | 2474 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% | 44,208 psi | 71% | 2224 fps | 100% |
| Accurate 2460 | <<locked>> | 80% | 47,979 psi | 77% | 2316 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 36,709 psi | 59% | 2156 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 41,756 psi | 67% | 2270 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 41,756 psi | 67% | 2270 fps | 100% |
| Accurate 2700 | <<locked>> | 92% | 48,530 psi | 78% | 2310 fps | 95.2% |
| Accurate 4064 | <<locked>> | 80% | 34,722 psi | 56% | 2149 fps | 99.9% |
| Accurate 4350 | <<locked>> | 88% | 32,605 psi | 52% | 2165 fps | 95% |
| Accurate LT-30 | <<locked>> | 80% | 52,533 psi | 84% | 2287 fps | 100% |
| Accurate LT-32 | <<locked>> | 80% | 52,939 psi | 85% | 2310 fps | 100% |
| ADI AR 2206H | <<locked>> | 80% | 40,495 psi | 65% | 2244 fps | 98.4% |
| ADI AR 2208 | <<locked>> | 80% | 34,606 psi | 55% | 2116 fps | 96.2% |
| ADI Benchmark 8208 | <<locked>> | 80% | 42,511 psi | 68% | 2254 fps | 99.5% |
| Alliant AR-Comp | <<locked>> | 80% | 42,134 psi | 68% | 2244 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 80% | 49,472 psi | 79% | 2425 fps | 99.9% |
| Alliant Power Pro 2000-MR | 59.5 gr | 80% | 36,593 psi | 59% | 2260 fps | 96.5% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 33,808 psi | 54% | 2136 fps | 97.7% |
| Alliant Reloder-10x | <<locked>> | 80% | 49,937 psi | 80% | 2303 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 36,361 psi | 58% | 2185 fps | 97% |
| Alliant Reloder-16 | <<locked>> | 88% | 33,779 psi | 54% | 2182 fps | 95.1% |
| Alliant Reloder-17 | <<locked>> | 80% | 29,211 psi | 47% | 2096 fps | 95% |
| Alliant Reloder-23 | <<locked>> | 96% | 30,429 psi | 49% | 2136 fps | 95.4% |
| Baschieri & Pellagri 106 | <<locked>> | 80% | 51,488 psi | 83% | 2290 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 39,465 psi | 63% | 2244 fps | 97.2% |
| Bofors RP3 | <<locked>> | 80% | 33,083 psi | 53% | 2133 fps | 97.6% |
| Bofors RP7 | <<locked>> | 94% | 47,181 psi | 76% | 2333 fps | 95.3% |
| Hodgdon Benchmark | <<locked>> | 80% | 44,585 psi | 71% | 2247 fps | 99.9% |
| Hodgdon BL-C2 | <<locked>> | 80% | 40,901 psi | 66% | 2274 fps | 99.6% |
| Hodgdon CFE223 | <<locked>> | 80% | 44,918 psi | 72% | 2388 fps | 98.9% |
| Hodgdon H322 | <<locked>> | 80% | 45,165 psi | 72% | 2287 fps | 100% |
| Hodgdon H335 | <<locked>> | 80% | 52,141 psi | 84% | 2395 fps | 100% |
| Hodgdon H380 | <<locked>> | 82% | 36,564 psi | 59% | 2185 fps | 95.6% |
| Hodgdon H414 | <<locked>> | 92% | 44,527 psi | 71% | 2379 fps | 95.5% |
| Hodgdon H4350 | <<locked>> | 98% | 48,921 psi | 78% | 2395 fps | 95% |
| Hodgdon H4895 | <<locked>> | 80% | 40,843 psi | 65% | 2254 fps | 98.9% |
| Hodgdon Hybrid 100V | <<locked>> | 86% | 29,037 psi | 47% | 2051 fps | 95.2% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 34,563 psi | 55% | 2182 fps | 98% |
| Hodgdon Superformance | <<locked>> | 96% | 46,847 psi | 75% | 2428 fps | 95.2% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,063 psi | 42% | 1293 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 36,463 psi | 58% | 2159 fps | 98% |
| IMR 3031 | <<locked>> | 80% | 36,796 psi | 59% | 2198 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 33,823 psi | 54% | 2096 fps | 96.2% |
| IMR 4166 Enduron | <<locked>> | 90% | 45,745 psi | 73% | 2280 fps | 95.6% |
| IMR 4198 | <<locked>> | 80% | 50,386 psi | 81% | 2267 fps | 100% |
| IMR 4350 | <<locked>> | 98% | 46,833 psi | 75% | 2352 fps | 95.3% |
| IMR 4451 Enduron | <<locked>> | 92% | 46,108 psi | 74% | 2316 fps | 95.6% |
| IMR 4831 | <<locked>> | 92% | 32,634 psi | 52% | 2149 fps | 95% |
| IMR 4895 | <<locked>> | 80% | 37,217 psi | 60% | 2211 fps | 97.8% |
| IMR 8208 XBR | <<locked>> | 80% | 42,511 psi | 68% | 2254 fps | 99.5% |
| Lovex D073.4 | <<locked>> | 80% | 49,879 psi | 80% | 2343 fps | 100% |
| Lovex D073.5 | <<locked>> | 80% | 47,834 psi | 77% | 2326 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 39,088 psi | 63% | 2228 fps | 99.9% |
| Lovex S060 | <<locked>> | 80% | 41,060 psi | 66% | 2192 fps | 98.5% |
| Lovex S062 | <<locked>> | 80% | 36,013 psi | 58% | 2149 fps | 98.6% |
| Lovex S065 | <<locked>> | 88% | 37,768 psi | 61% | 2185 fps | 95% |
| Lovex S070 | <<locked>> | 94% | 42,844 psi | 69% | 2293 fps | 95.2% |
| Norma 201 | <<locked>> | 80% | 39,784 psi | 64% | 2205 fps | 99.2% |
| Norma 202 | <<locked>> | 80% | 39,871 psi | 64% | 2215 fps | 100% |
| Norma 203B | <<locked>> | 80% | 35,752 psi | 57% | 2175 fps | 97.4% |
| Norma URP | <<locked>> | 90% | 35,621 psi | 57% | 2218 fps | 95.8% |
| Ramshot Big Game | <<locked>> | 80% | 35,201 psi | 56% | 2188 fps | 97% |
| Ramshot Hunter | <<locked>> | 96% | 42,380 psi | 68% | 2346 fps | 95.8% |
| Ramshot TAC | <<locked>> | 80% | 42,409 psi | 68% | 2254 fps | 96.5% |
| Ramshot Wild Boar | <<locked>> | 80% | 41,713 psi | 67% | 2274 fps | 98.6% |
| Ramshot X-Terminator | <<locked>> | 80% | 45,992 psi | 74% | 2297 fps | 99.1% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,397 psi | 42% | 1325 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 47,718 psi | 77% | 2323 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 86% | 42,119 psi | 68% | 2260 fps | 95.4% |
| ReloadSwiss RS 52 | 57.7 gr | 80% | 37,739 psi | 61% | 2270 fps | 97.4% |
| ReloadSwiss RS 60 | 58.6 gr | 80% | 31,096 psi | 50% | 2156 fps | 98.5% |
| ReloadSwiss RS 62 | <<locked>> | 90% | 34,925 psi | 56% | 2231 fps | 95.3% |
| ReloadSwiss RS 70 | <<locked>> | 92% | 38,058 psi | 61% | 2287 fps | 95.2% |
| Rottweil R 901 | <<locked>> | 80% | 43,584 psi | 70% | 2241 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 37,840 psi | 61% | 2165 fps | 98.9% |
| Rottweil R 903 | <<locked>> | 80% | 31,212 psi | 50% | 2087 fps | 96.7% |
| Rottweil R 907 | <<locked>> | 94% | 47,181 psi | 76% | 2333 fps | 95.3% |
| Shooters World Long Rifle | <<locked>> | 88% | 37,768 psi | 61% | 2185 fps | 95% |
| Shooters World Match Rifle | <<locked>> | 80% | 39,088 psi | 63% | 2228 fps | 99.9% |
| Shooters World Precision | <<locked>> | 80% | 36,013 psi | 58% | 2149 fps | 98.6% |
| Shooters World SW4350 | <<locked>> | 94% | 42,844 psi | 69% | 2293 fps | 95.2% |
| Shooters World Tactical Rifle | <<locked>> | 80% | 50,502 psi | 81% | 2343 fps | 99.9% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 32,358 psi | 52% | 2133 fps | 96.1% |
| SNPE Vectan SP 3 | <<locked>> | 80% | 50,662 psi | 81% | 2320 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 40,480 psi | 65% | 2231 fps | 96.6% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 39,146 psi | 63% | 2221 fps | 98.1% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 41,394 psi | 66% | 2169 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 34,142 psi | 55% | 2057 fps | 99.9% |
| SNPE Vectan Tubal 7000 | <<locked>> | 94% | 44,817 psi | 72% | 2267 fps | 95.4% |
| Somchem S321 | <<locked>> | 80% | 45,759 psi | 73% | 2323 fps | 99.9% |
| Somchem S335 | <<locked>> | 80% | 40,843 psi | 65% | 2172 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 40,219 psi | 64% | 2231 fps | 98.3% |
| Somchem S355 | <<locked>> | 80% | 32,285 psi | 52% | 2096 fps | 96.8% |
| Somchem S365 | <<locked>> | 84% | 26,426 psi | 42% | 2034 fps | 95.5% |
| Unknown powder | <<locked>> | 88% | 36,579 psi | 59% | 2221 fps | 95.3% |
| Vihtavuori N130 | <<locked>> | 80% | 46,818 psi | 75% | 2224 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 41,568 psi | 67% | 2165 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 37,014 psi | 59% | 2156 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 37,724 psi | 60% | 2159 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 30,574 psi | 49% | 2044 fps | 97.6% |
| Vihtavuori N160 | <<locked>> | 88% | 35,070 psi | 56% | 2175 fps | 95.5% |
| Vihtavuori N530 | <<locked>> | 80% | 42,467 psi | 68% | 2247 fps | 99.5% |
| Vihtavuori N540 | <<locked>> | 80% | 36,172 psi | 58% | 2149 fps | 99.8% |
| Vihtavuori N550 | <<locked>> | 88% | 34,389 psi | 55% | 2178 fps | 95.1% |
| Vihtavuori N555 | <<locked>> | 96% | 32,300 psi | 52% | 2201 fps | 95.6% |
| Winchester 6.5 StaBALL | <<locked>> | 82% | 29,225 psi | 47% | 2021 fps | 95.2% |
| Winchester 748 | <<locked>> | 80% | 44,991 psi | 72% | 2339 fps | 100% |
| Winchester 760 | <<locked>> | 92% | 44,527 psi | 71% | 2379 fps | 95.5% |
| Winchester StaBALL Match | <<locked>> | 80% | 47,601 psi | 76% | 2372 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 108 powders for .375 H&H Mag. loaded with the .375 | 300gr | Speer TBBC. Alliant Reloder-17 delivers the highest muzzle velocity at 2,592 fps; across all powders the maximum-charge window runs from 1,447 fps to 2,592 fps. Accurate 4350 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 (430 MPa), the top charges use 55–90 %, leaving at least 10 % headroom. The 300.0 gr projectile in 0.375" calls for a 1:6.0 twist; slower twists will usually not stabilise this weight. Accurate 4350, Alliant Reloder-16, Alliant Reloder-17 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, ReloadSwiss RS 60, ReloadSwiss RS 52 rank at the top here: for .375 H&H Mag. with the .375 | 300gr | Speer TBBC 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.