Load Specifications
Bullet Manufacturer:Woodleigh
Bullet Weight:300 gr
Bullet Diameter:0.375"
Bullet Length:<<locked>>
Caliber:37 XC load data
Case Length (l3):3.087"
Cartridge Length (C.O.L.):<<locked>>
Case Capacity:139.8 Grains of Water
Primer Size:Large Rifle Magnum (LRM)
Barrel Length:30"
Max. allowed Pressure:69,618 psi
Recommended Twist Rate:1:6.0
Load data in caliber 37 XC with .375 | 300gr | Woodleigh PP SN bullet and 99 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Accurate MAGPRO, Accurate High Country and Alliant Reloder-26.
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: 30"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2700 | <<locked>> | 82% | 61,017 psi | 88% | 2835 fps | 100% |
| Accurate 3100 | <<locked>> | 98% | 62,018 psi | 89% | 2904 fps | 100% |
| Accurate 4064 | <<locked>> | 82% | 61,293 psi | 88% | 2792 fps | 100% |
| Accurate 4350 | <<locked>> | 88% | 59,567 psi | 86% | 2887 fps | 100% |
| Accurate High Country | <<locked>> | 94% | 59,611 psi | 86% | 3025 fps | 100% |
| Accurate MAGPRO | <<locked>> | 96% | 60,597 psi | 87% | 3031 fps | 99.7% |
| ADI APS 450 | <<locked>> | 84% | 62,990 psi | 90% | 2211 fps | 100% |
| ADI AR 2208 | <<locked>> | 84% | 60,278 psi | 87% | 2835 fps | 100% |
| ADI AR 2209 | <<locked>> | 94% | 60,176 psi | 86% | 2953 fps | 100% |
| ADI AR 2213 | <<locked>> | 98% | 61,931 psi | 89% | 3022 fps | 100% |
| ADI AR 2217ᴾ | <<locked>> | 100% | 48,399 psi | 70% | 2812 fps | 99.3% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 43,134 psi | 62% | 2785 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 94% | 60,292 psi | 87% | 2949 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 84% | 61,859 psi | 89% | 2854 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 82% | 61,801 psi | 89% | 2881 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 90% | 60,307 psi | 87% | 2936 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 86% | 61,902 psi | 89% | 2953 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 94% | 59,495 psi | 85% | 2943 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 98% | 61,728 psi | 89% | 3012 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 62,859 psi | 90% | 2956 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 54,505 psi | 78% | 2933 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 94% | 59,872 psi | 86% | 3018 fps | 100% |
| Baschieri & Pellagri 109 | <<locked>> | 98% | 59,582 psi | 86% | 2927 fps | 98.5% |
| Bofors RP15ᴾ | <<locked>> | 100% | 60,379 psi | 87% | 2995 fps | 100% |
| Bofors RP3 | <<locked>> | 82% | 59,422 psi | 85% | 2828 fps | 100% |
| Bofors RP30ᴾ | <<locked>> | 100% | 50,488 psi | 73% | 2887 fps | 99.7% |
| Bofors RP5 | <<locked>> | 98% | 61,728 psi | 89% | 3012 fps | 100% |
| Bofors RP7 | <<locked>> | 88% | 61,743 psi | 89% | 2884 fps | 100% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 53,417 psi | 77% | 2897 fps | 99.9% |
| Hodgdon H380 | <<locked>> | 82% | 59,350 psi | 85% | 2851 fps | 100% |
| Hodgdon H414 | <<locked>> | 88% | 61,250 psi | 88% | 2946 fps | 100% |
| Hodgdon H4350 | <<locked>> | 86% | 60,133 psi | 86% | 2904 fps | 100% |
| Hodgdon H4831 | <<locked>> | 96% | 61,815 psi | 89% | 2956 fps | 99.8% |
| Hodgdon H4831 SC | <<locked>> | 96% | 60,582 psi | 87% | 2940 fps | 99.7% |
| Hodgdon Hybrid 100V | <<locked>> | 92% | 60,495 psi | 87% | 2848 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 53,359 psi | 77% | 3012 fps | 100% |
| Hodgdon Superformance | <<locked>> | 88% | 62,366 psi | 90% | 2992 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,028 psi | 53% | 1752 fps | 100% |
| IMR 4064 | <<locked>> | 82% | 59,741 psi | 86% | 2815 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 82% | 62,076 psi | 89% | 2861 fps | 100% |
| IMR 4350 | <<locked>> | 90% | 59,625 psi | 86% | 2874 fps | 100% |
| IMR 4451 Enduron | <<locked>> | 86% | 59,480 psi | 85% | 2854 fps | 100% |
| IMR 4831 | <<locked>> | 90% | 59,669 psi | 86% | 2874 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 96% | 62,497 psi | 90% | 2933 fps | 99.9% |
| IMR 7828 SSC | <<locked>> | 98% | 59,596 psi | 86% | 3002 fps | 100% |
| IMR 8133 Enduronᴾ | <<locked>> | 100% | 38,740 psi | 56% | 2697 fps | 97.7% |
| Lovex S062 | <<locked>> | 82% | 60,191 psi | 86% | 2802 fps | 100% |
| Lovex S065 | <<locked>> | 88% | 60,162 psi | 86% | 2851 fps | 100% |
| Lovex S070 | <<locked>> | 90% | 62,076 psi | 89% | 2900 fps | 100% |
| Lovex S071ᴾ | <<locked>> | 100% | 55,317 psi | 79% | 2822 fps | 100% |
| Norma 203B | <<locked>> | 82% | 61,119 psi | 88% | 2864 fps | 100% |
| Norma 204 | <<locked>> | 90% | 61,017 psi | 88% | 2940 fps | 100% |
| Norma 217ᴾ | <<locked>> | 100% | 38,696 psi | 56% | 2720 fps | 99.4% |
| Norma MRP | <<locked>> | 96% | 61,917 psi | 89% | 3035 fps | 100% |
| Norma URP | <<locked>> | 90% | 61,554 psi | 88% | 2917 fps | 100% |
| Ramshot Big Game | <<locked>> | 82% | 62,511 psi | 90% | 2894 fps | 100% |
| Ramshot Grand | <<locked>> | 98% | 60,684 psi | 87% | 3022 fps | 100% |
| Ramshot Hunter | <<locked>> | 90% | 60,321 psi | 87% | 2933 fps | 100% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 58,842 psi | 85% | 2949 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,927 psi | 54% | 1795 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 84% | 62,874 psi | 90% | 2890 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 84% | 61,525 psi | 88% | 2933 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 88% | 59,582 psi | 86% | 2910 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 90% | 62,163 psi | 89% | 2999 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 53,998 psi | 78% | 3009 fps | 100% |
| ReloadSwiss RS 80ᴾ | <<locked>> | 100% | 48,718 psi | 70% | 2904 fps | 98.7% |
| Rottweil R 902 | <<locked>> | 82% | 62,033 psi | 89% | 2808 fps | 100% |
| Rottweil R 903 | <<locked>> | 84% | 59,640 psi | 86% | 2825 fps | 100% |
| Rottweil R 904 | <<locked>> | 94% | 61,351 psi | 88% | 2917 fps | 99.9% |
| Rottweil R 905 | <<locked>> | 94% | 59,132 psi | 85% | 2930 fps | 100% |
| Rottweil R 907 | <<locked>> | 88% | 61,743 psi | 89% | 2884 fps | 100% |
| Shooters World Long Rifle | <<locked>> | 88% | 60,162 psi | 86% | 2851 fps | 100% |
| Shooters World Precision | <<locked>> | 82% | 60,191 psi | 86% | 2802 fps | 100% |
| Shooters World SW4350 | <<locked>> | 90% | 62,076 psi | 89% | 2900 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 84% | 61,076 psi | 88% | 2884 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 86% | 62,961 psi | 90% | 2726 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 88% | 59,596 psi | 86% | 2808 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 96% | 62,671 psi | 90% | 2976 fps | 100% |
| Somchem S355 | <<locked>> | 86% | 62,874 psi | 90% | 2864 fps | 100% |
| Somchem S361 | <<locked>> | 92% | 59,350 psi | 85% | 2861 fps | 99.6% |
| Somchem S365 | <<locked>> | 92% | 62,163 psi | 89% | 2913 fps | 100% |
| Somchem S385 | <<locked>> | 94% | 59,654 psi | 86% | 2897 fps | 100% |
| Vihtavuori N135 | <<locked>> | 82% | 62,961 psi | 90% | 2756 fps | 100% |
| Vihtavuori N140 | <<locked>> | 82% | 62,743 psi | 90% | 2772 fps | 100% |
| Vihtavuori N150 | <<locked>> | 86% | 60,394 psi | 87% | 2785 fps | 100% |
| Vihtavuori N160 | <<locked>> | 88% | 59,654 psi | 86% | 2858 fps | 100% |
| Vihtavuori N165 | <<locked>> | 98% | 59,117 psi | 85% | 2877 fps | 100% |
| Vihtavuori N170ᴾ | <<locked>> | 100% | 53,882 psi | 77% | 2838 fps | 96% |
| Vihtavuori N540 | <<locked>> | 82% | 60,901 psi | 87% | 2779 fps | 100% |
| Vihtavuori N550 | <<locked>> | 90% | 62,584 psi | 90% | 2913 fps | 100% |
| Vihtavuori N555 | <<locked>> | 96% | 61,409 psi | 88% | 2940 fps | 100% |
| Vihtavuori N560 | <<locked>> | 96% | 61,656 psi | 89% | 3041 fps | 99.9% |
| Vihtavuori N565ᴾ | <<locked>> | 100% | 57,261 psi | 82% | 2963 fps | 99.8% |
| Vihtavuori N568ᴾ | <<locked>> | 100% | 50,125 psi | 72% | 2910 fps | 98.5% |
| Vihtavuori N570ᴾ | <<locked>> | 100% | 47,253 psi | 68% | 2897 fps | 96.1% |
| Winchester 6.5 StaBALL | <<locked>> | 88% | 59,190 psi | 85% | 2812 fps | 100% |
| Winchester 760 | <<locked>> | 88% | 61,395 psi | 88% | 2946 fps | 100% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 61,046 psi | 88% | 3054 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 96% | 59,741 psi | 86% | 2897 fps | 100% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 30"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2700 | <<locked>> | 80% | 57,159 psi | 82% | 2785 fps | 100% |
| Accurate 3100 | <<locked>> | 80% | 33,910 psi | 49% | 2457 fps | 98.9% |
| Accurate 4064 | <<locked>> | 80% | 57,653 psi | 83% | 2749 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 45,498 psi | 65% | 2687 fps | 100% |
| Accurate High Country | 95.2 gr | 80% | 36,550 psi | 53% | 2618 fps | 96.7% |
| Accurate MAGPRO | 99.4 gr | 82% | 36,970 psi | 53% | 2618 fps | 95.3% |
| ADI APS 450 | <<locked>> | 80% | 58,900 psi | 85% | 2159 fps | 100% |
| ADI AR 2208 | <<locked>> | 80% | 53,403 psi | 77% | 2743 fps | 100% |
| ADI AR 2209 | <<locked>> | 80% | 37,927 psi | 54% | 2579 fps | 97.8% |
| ADI AR 2213 | <<locked>> | 80% | 33,866 psi | 49% | 2510 fps | 95.1% |
| ADI AR 2217 | <<locked>> | 90% | 34,896 psi | 50% | 2536 fps | 95.8% |
| ADI AR 2225 | <<locked>> | 86% | 27,572 psi | 40% | 2392 fps | 95.8% |
| Alliant Power Pro Varmint | <<locked>> | 80% | 38,305 psi | 55% | 2579 fps | 97.9% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 54,665 psi | 79% | 2762 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 58,175 psi | 84% | 2835 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 43,540 psi | 63% | 2694 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 80% | 50,169 psi | 72% | 2799 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 37,971 psi | 55% | 2575 fps | 97.9% |
| Alliant Reloder-22 | <<locked>> | 80% | 33,794 psi | 49% | 2526 fps | 96.9% |
| Alliant Reloder-23 | <<locked>> | 80% | 32,547 psi | 47% | 2484 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 28,384 psi | 41% | 2408 fps | 98.1% |
| Alliant Reloder-26 | 98.1 gr | 80% | 35,418 psi | 51% | 2625 fps | 99.9% |
| Baschieri & Pellagri 109 | <<locked>> | 88% | 43,729 psi | 63% | 2654 fps | 95.1% |
| Bofors RP15 | <<locked>> | 80% | 31,488 psi | 45% | 2464 fps | 95.8% |
| Bofors RP3 | <<locked>> | 80% | 55,680 psi | 80% | 2782 fps | 100% |
| Bofors RP30 | <<locked>> | 86% | 31,459 psi | 45% | 2500 fps | 95.1% |
| Bofors RP5 | <<locked>> | 80% | 33,794 psi | 49% | 2526 fps | 96.9% |
| Bofors RP7 | <<locked>> | 80% | 48,211 psi | 69% | 2687 fps | 99.8% |
| Hodgdon H1000 | <<locked>> | 86% | 33,330 psi | 48% | 2500 fps | 95.9% |
| Hodgdon H380 | <<locked>> | 80% | 55,506 psi | 80% | 2802 fps | 100% |
| Hodgdon H414 | <<locked>> | 80% | 47,007 psi | 68% | 2736 fps | 99.9% |
| Hodgdon H4350 | <<locked>> | 80% | 49,676 psi | 71% | 2749 fps | 99.7% |
| Hodgdon H4831 | <<locked>> | 80% | 35,984 psi | 52% | 2516 fps | 95.3% |
| Hodgdon H4831 SC | <<locked>> | 80% | 35,462 psi | 51% | 2503 fps | 95.1% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 41,089 psi | 59% | 2575 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 82% | 29,573 psi | 42% | 2484 fps | 95.5% |
| Hodgdon Superformance | <<locked>> | 80% | 46,543 psi | 67% | 2766 fps | 99.9% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,833 psi | 40% | 1568 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 56,173 psi | 81% | 2769 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 80% | 58,349 psi | 84% | 2815 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 43,700 psi | 63% | 2628 fps | 99.5% |
| IMR 4451 Enduron | <<locked>> | 80% | 49,530 psi | 71% | 2710 fps | 100% |
| IMR 4831 | <<locked>> | 80% | 43,279 psi | 62% | 2635 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 37,942 psi | 55% | 2520 fps | 96.1% |
| IMR 7828 SSC | <<locked>> | 82% | 34,722 psi | 50% | 2546 fps | 95.6% |
| IMR 8133 Enduron | <<locked>> | 94% | 31,908 psi | 46% | 2530 fps | 95% |
| Lovex S062 | <<locked>> | 80% | 56,652 psi | 81% | 2759 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 47,137 psi | 68% | 2661 fps | 100% |
| Lovex S070 | <<locked>> | 80% | 45,498 psi | 65% | 2657 fps | 99.9% |
| Lovex S071 | <<locked>> | 80% | 29,211 psi | 42% | 2343 fps | 97.6% |
| Norma 203B | <<locked>> | 80% | 57,537 psi | 83% | 2822 fps | 100% |
| Norma 204 | <<locked>> | 80% | 43,511 psi | 63% | 2667 fps | 98.9% |
| Norma 217 | <<locked>> | 90% | 27,949 psi | 40% | 2441 fps | 95.6% |
| Norma MRP | <<locked>> | 80% | 35,230 psi | 51% | 2589 fps | 98.6% |
| Norma URP | <<locked>> | 80% | 44,599 psi | 64% | 2674 fps | 100% |
| Ramshot Big Game | <<locked>> | 80% | 58,566 psi | 84% | 2848 fps | 100% |
| Ramshot Grand | <<locked>> | 82% | 34,200 psi | 49% | 2549 fps | 95.9% |
| Ramshot Hunter | <<locked>> | 80% | 43,337 psi | 62% | 2677 fps | 100% |
| Ramshot Magnum | <<locked>> | 80% | 28,369 psi | 41% | 2379 fps | 95.4% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,340 psi | 41% | 1604 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 55,187 psi | 79% | 2792 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 53,287 psi | 77% | 2835 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 45,252 psi | 65% | 2707 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 43,482 psi | 62% | 2730 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 80% | 26,614 psi | 38% | 2388 fps | 95% |
| ReloadSwiss RS 80 | <<locked>> | 92% | 36,274 psi | 52% | 2651 fps | 95.4% |
| Rottweil R 902 | <<locked>> | 80% | 58,392 psi | 84% | 2766 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 52,460 psi | 75% | 2733 fps | 100% |
| Rottweil R 904 | <<locked>> | 80% | 39,349 psi | 57% | 2556 fps | 97.1% |
| Rottweil R 905 | <<locked>> | 80% | 37,260 psi | 54% | 2559 fps | 97.9% |
| Rottweil R 907 | <<locked>> | 80% | 48,211 psi | 69% | 2687 fps | 99.8% |
| Shooters World Long Rifle | <<locked>> | 80% | 47,137 psi | 68% | 2661 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 56,652 psi | 81% | 2759 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 45,498 psi | 65% | 2657 fps | 99.9% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 53,650 psi | 77% | 2789 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 52,431 psi | 75% | 2602 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 46,166 psi | 66% | 2612 fps | 99.9% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 36,927 psi | 53% | 2556 fps | 97.8% |
| Somchem S355 | <<locked>> | 80% | 52,257 psi | 75% | 2726 fps | 100% |
| Somchem S361 | <<locked>> | 80% | 39,900 psi | 57% | 2543 fps | 96.5% |
| Somchem S365 | <<locked>> | 80% | 41,611 psi | 60% | 2631 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 37,869 psi | 54% | 2543 fps | 98.6% |
| Vihtavuori N135 | <<locked>> | 80% | 59,176 psi | 85% | 2710 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 59,088 psi | 85% | 2730 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 50,024 psi | 72% | 2651 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 46,050 psi | 66% | 2664 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 32,750 psi | 47% | 2421 fps | 96.9% |
| Vihtavuori N170 | <<locked>> | 98% | 50,473 psi | 73% | 2785 fps | 95.2% |
| Vihtavuori N540 | <<locked>> | 80% | 57,101 psi | 82% | 2733 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 45,295 psi | 65% | 2671 fps | 100% |
| Vihtavuori N555 | <<locked>> | 80% | 36,521 psi | 52% | 2556 fps | 100% |
| Vihtavuori N560 | <<locked>> | 80% | 35,462 psi | 51% | 2575 fps | 95.4% |
| Vihtavuori N565 | <<locked>> | 86% | 35,592 psi | 51% | 2575 fps | 95.9% |
| Vihtavuori N568 | <<locked>> | 92% | 37,884 psi | 54% | 2671 fps | 95.2% |
| Vihtavuori N570 | <<locked>> | 98% | 44,222 psi | 64% | 2838 fps | 95.2% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 44,991 psi | 65% | 2621 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 47,137 psi | 68% | 2740 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 80% | 28,819 psi | 41% | 2516 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 34,418 psi | 49% | 2467 fps | 96.9% |
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 99 powders for 37 XC loaded with the .375 | 300gr | Woodleigh PP SN. Winchester StaBALL HD delivers the highest muzzle velocity at 3,054 fps; across all powders the maximum-charge window runs from 1,752 fps to 3,054 fps. ADI AR 2217 gives the best case fill at 100 %, and 99 of the 99 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (480 MPa), the top charges use 53–90 %, 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. ADI AR 2217, ADI AR 2225, Alliant Reloder-23 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. Accurate MAGPRO, Accurate High Country, Alliant Reloder-26 rank at the top here: for 37 XC with the .375 | 300gr | Woodleigh PP SN 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.