Load Specifications
Load data in caliber .375 Chey Tac with .375 | 400gr | MAKER REX SUB bullet and 44 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are ADI AR 2218, Vihtavuori N570 and Alliant Reloder-50.
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: 29"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 3100 | <<locked>> | 82% | 56,188 psi | 88% | 2470 fps | 100% |
| Accurate 8700ᴾ | <<locked>> | 100% | 57,014 psi | 89% | 2621 fps | 100% |
| ADI AR 2213 | <<locked>> | 82% | 56,478 psi | 89% | 2585 fps | 100% |
| ADI AR 2217 | <<locked>> | 90% | 56,478 psi | 89% | 2579 fps | 100% |
| ADI AR 2218 | <<locked>> | 94% | 57,174 psi | 90% | 2730 fps | 100% |
| ADI AR 2225 | <<locked>> | 92% | 56,521 psi | 89% | 2598 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 82% | 56,971 psi | 89% | 2575 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 82% | 55,448 psi | 87% | 2477 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 86% | 56,521 psi | 89% | 2556 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 90% | 54,911 psi | 86% | 2644 fps | 100% |
| Alliant Reloder-50 | <<locked>> | 94% | 55,071 psi | 86% | 2648 fps | 100% |
| Baschieri & Pellagri 109 | <<locked>> | 84% | 56,202 psi | 88% | 2559 fps | 100% |
| Bofors RP15 | <<locked>> | 84% | 56,463 psi | 88% | 2569 fps | 100% |
| Bofors RP30 | <<locked>> | 88% | 56,376 psi | 88% | 2595 fps | 100% |
| Bofors RP5 | <<locked>> | 82% | 56,971 psi | 89% | 2575 fps | 100% |
| Hodgdon 50BMG | <<locked>> | 94% | 57,029 psi | 89% | 2657 fps | 96.8% |
| Hodgdon H1000 | <<locked>> | 86% | 53,838 psi | 84% | 2539 fps | 100% |
| Hodgdon H4831 SC | <<locked>> | 82% | 57,493 psi | 90% | 2552 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 86% | 56,826 psi | 89% | 2651 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 38,247 psi | 60% | 1604 fps | 100% |
| Hodgdon US 869 | <<locked>> | 98% | 57,537 psi | 90% | 2631 fps | 98.7% |
| IMR 7828 SSC | <<locked>> | 82% | 55,201 psi | 87% | 2572 fps | 100% |
| IMR 7977 Enduron | <<locked>> | 88% | 56,927 psi | 89% | 2523 fps | 99.3% |
| IMR 8133 Enduron | <<locked>> | 94% | 55,230 psi | 87% | 2598 fps | 100% |
| Lovex D100 | <<locked>> | 90% | 54,433 psi | 85% | 2533 fps | 98.5% |
| Lovex S071 | <<locked>> | 86% | 54,998 psi | 86% | 2457 fps | 100% |
| Norma 217 | <<locked>> | 94% | 57,014 psi | 89% | 2612 fps | 100% |
| Ramshot Grand | <<locked>> | 82% | 56,840 psi | 89% | 2592 fps | 100% |
| Ramshot LRT | <<locked>> | 94% | 56,507 psi | 89% | 2671 fps | 98.8% |
| Ramshot Magnum | <<locked>> | 84% | 55,013 psi | 86% | 2526 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 39,334 psi | 62% | 1644 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 86% | 57,348 psi | 90% | 2638 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 88% | 55,970 psi | 88% | 2631 fps | 100% |
| Shooters World 50 BMG | <<locked>> | 90% | 54,433 psi | 85% | 2533 fps | 98.5% |
| SNPE Vectan SP 13 | <<locked>> | 98% | 54,578 psi | 86% | 2575 fps | 100% |
| Vihtavuori 20N29ᴾ | <<locked>> | 100% | 51,561 psi | 81% | 2559 fps | 99.2% |
| Vihtavuori 24N41 | <<locked>> | 94% | 54,360 psi | 85% | 2585 fps | 98.2% |
| Vihtavuori N165 | <<locked>> | 84% | 57,145 psi | 90% | 2500 fps | 100% |
| Vihtavuori N170 | <<locked>> | 88% | 56,550 psi | 89% | 2566 fps | 99.9% |
| Vihtavuori N565 | <<locked>> | 84% | 54,215 psi | 85% | 2556 fps | 100% |
| Vihtavuori N568 | <<locked>> | 88% | 56,376 psi | 88% | 2631 fps | 100% |
| Vihtavuori N570 | <<locked>> | 88% | 54,288 psi | 85% | 2651 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 82% | 57,116 psi | 90% | 2566 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 82% | 56,579 psi | 89% | 2507 fps | 100% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 29"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 3100 | <<locked>> | 80% | 52,663 psi | 83% | 2428 fps | 100% |
| Accurate 8700 | <<locked>> | 84% | 31,618 psi | 50% | 2198 fps | 96% |
| ADI AR 2213 | <<locked>> | 80% | 52,692 psi | 83% | 2536 fps | 100% |
| ADI AR 2217 | <<locked>> | 80% | 39,682 psi | 62% | 2339 fps | 100% |
| ADI AR 2218 | 118.1 gr | 80% | 33,794 psi | 53% | 2320 fps | 97.6% |
| ADI AR 2225 | <<locked>> | 80% | 36,941 psi | 58% | 2323 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 80% | 53,287 psi | 84% | 2526 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 80% | 51,967 psi | 81% | 2434 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 46,180 psi | 72% | 2425 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 80% | 37,811 psi | 59% | 2365 fps | 98.5% |
| Alliant Reloder-50 | 119.9 gr | 80% | 32,663 psi | 51% | 2254 fps | 96.4% |
| Baschieri & Pellagri 109 | <<locked>> | 80% | 49,356 psi | 77% | 2464 fps | 99.9% |
| Bofors RP15 | <<locked>> | 80% | 49,632 psi | 78% | 2477 fps | 100% |
| Bofors RP30 | <<locked>> | 80% | 42,960 psi | 67% | 2405 fps | 100% |
| Bofors RP5 | <<locked>> | 80% | 53,287 psi | 84% | 2526 fps | 100% |
| Hodgdon 50BMG | <<locked>> | 90% | 49,617 psi | 78% | 2546 fps | 95.1% |
| Hodgdon H1000 | <<locked>> | 80% | 43,366 psi | 68% | 2398 fps | 100% |
| Hodgdon H4831 SC | <<locked>> | 80% | 53,780 psi | 84% | 2507 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 80% | 45,832 psi | 72% | 2507 fps | 100% |
| Hodgdon TrailBoss | <<locked>> | 80% | 28,805 psi | 45% | 1434 fps | 100% |
| Hodgdon US 869 | <<locked>> | 90% | 43,352 psi | 68% | 2418 fps | 95.8% |
| IMR 7828 SSC | <<locked>> | 80% | 51,634 psi | 81% | 2526 fps | 100% |
| IMR 7977 Enduron | <<locked>> | 80% | 44,005 psi | 69% | 2329 fps | 97.3% |
| IMR 8133 Enduron | <<locked>> | 80% | 34,316 psi | 54% | 2264 fps | 99.7% |
| Lovex D100 | <<locked>> | 82% | 40,973 psi | 64% | 2320 fps | 95.5% |
| Lovex S071 | <<locked>> | 80% | 45,382 psi | 71% | 2333 fps | 100% |
| Norma 217 | <<locked>> | 80% | 35,012 psi | 55% | 2283 fps | 100% |
| Ramshot Grand | <<locked>> | 80% | 52,765 psi | 83% | 2539 fps | 100% |
| Ramshot LRT | <<locked>> | 86% | 42,380 psi | 66% | 2444 fps | 95.8% |
| Ramshot Magnum | <<locked>> | 80% | 47,398 psi | 74% | 2428 fps | 100% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 29,631 psi | 46% | 1470 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 80% | 45,513 psi | 71% | 2487 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 80% | 41,481 psi | 65% | 2418 fps | 100% |
| Shooters World 50 BMG | <<locked>> | 82% | 40,973 psi | 64% | 2320 fps | 95.5% |
| SNPE Vectan SP 13 | <<locked>> | 82% | 31,314 psi | 49% | 2169 fps | 95.4% |
| Vihtavuori 20N29 | <<locked>> | 90% | 36,056 psi | 56% | 2293 fps | 95.6% |
| Vihtavuori 24N41 | <<locked>> | 88% | 43,845 psi | 69% | 2421 fps | 95.9% |
| Vihtavuori N165 | <<locked>> | 80% | 50,154 psi | 79% | 2411 fps | 100% |
| Vihtavuori N170 | <<locked>> | 80% | 43,076 psi | 68% | 2362 fps | 98.4% |
| Vihtavuori N565 | <<locked>> | 80% | 47,311 psi | 74% | 2457 fps | 100% |
| Vihtavuori N568 | <<locked>> | 80% | 42,424 psi | 66% | 2425 fps | 99.9% |
| Vihtavuori N570 | 115.7 gr | 80% | 40,625 psi | 64% | 2431 fps | 98.8% |
| Winchester StaBALL HD | <<locked>> | 80% | 53,142 psi | 83% | 2520 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 52,895 psi | 83% | 2461 fps | 100% |
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 44 powders for .375 Chey Tac loaded with the .375 | 400gr | MAKER REX SUB. ADI AR 2218 delivers the highest muzzle velocity at 2,730 fps; across all powders the maximum-charge window runs from 1,604 fps to 2,730 fps. Accurate 8700 gives the best case fill at 100 %, and 44 of the 44 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (440 MPa), the top charges use 60–90 %, leaving at least 10 % headroom. The 400.0 gr projectile in 0.375" calls for a 1:14.0 twist; slower twists will usually not stabilise this weight. Accurate 8700, Hodgdon TrailBoss, ReloadSwiss RS 14 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. ADI AR 2218, Vihtavuori N570, Alliant Reloder-50 rank at the top here: for .375 Chey Tac with the .375 | 400gr | MAKER REX SUB 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.