Load Specifications
Bullet:.375 | 270gr | Barnes X S
Bullet Manufacturer:Barnes
Bullet Weight:270 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 | 270gr | Barnes X S bullet and 105 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Accurate High Country, Alliant Reloder-26 and Vihtavuori N560.
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>> | 84% | 62,439 psi | 90% | 2959 fps | 100% |
| Accurate 3100ᴾ | <<locked>> | 100% | 62,961 psi | 90% | 3031 fps | 100% |
| Accurate 4064 | <<locked>> | 82% | 59,944 psi | 86% | 2894 fps | 100% |
| Accurate 4350 | <<locked>> | 90% | 60,742 psi | 87% | 3018 fps | 100% |
| Accurate High Country | <<locked>> | 96% | 59,712 psi | 86% | 3146 fps | 99.6% |
| Accurate MAGPRO | <<locked>> | 98% | 60,611 psi | 87% | 3143 fps | 99% |
| ADI APS 450 | <<locked>> | 84% | 62,830 psi | 90% | 2300 fps | 100% |
| ADI AR 2208 | <<locked>> | 86% | 61,293 psi | 88% | 2966 fps | 100% |
| ADI AR 2209 | <<locked>> | 96% | 60,495 psi | 87% | 3071 fps | 99.9% |
| ADI AR 2213ᴾ | <<locked>> | 100% | 62,018 psi | 89% | 3133 fps | 99.6% |
| ADI AR 2217ᴾ | <<locked>> | 100% | 46,050 psi | 66% | 2858 fps | 97.6% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 41,263 psi | 59% | 2835 fps | 99.3% |
| Alliant Power Pro 2000-MR | <<locked>> | 82% | 61,859 psi | 89% | 3110 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 96% | 60,539 psi | 87% | 3068 fps | 99.9% |
| Alliant Reloder- TS 15.5 | <<locked>> | 86% | 62,917 psi | 90% | 2989 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 82% | 59,379 psi | 85% | 2969 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 92% | 60,336 psi | 87% | 3064 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 88% | 62,004 psi | 89% | 3084 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 96% | 59,770 psi | 86% | 3058 fps | 99.9% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 61,714 psi | 89% | 3130 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 58,740 psi | 84% | 3038 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 51,111 psi | 73% | 3002 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 96% | 59,437 psi | 85% | 3143 fps | 100% |
| Baschieri & Pellagri 109ᴾ | <<locked>> | 100% | 60,176 psi | 86% | 3028 fps | 97.3% |
| Bofors RP15ᴾ | <<locked>> | 100% | 56,811 psi | 82% | 3061 fps | 99.7% |
| Bofors RP3 | <<locked>> | 84% | 61,046 psi | 88% | 2969 fps | 100% |
| Bofors RP30ᴾ | <<locked>> | 100% | 47,311 psi | 68% | 2943 fps | 98.4% |
| Bofors RP5ᴾ | <<locked>> | 100% | 61,714 psi | 89% | 3130 fps | 100% |
| Bofors RP7 | <<locked>> | 88% | 59,335 psi | 85% | 2963 fps | 100% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 50,299 psi | 72% | 2943 fps | 98.9% |
| Hodgdon H380 | <<locked>> | 84% | 60,785 psi | 87% | 2989 fps | 100% |
| Hodgdon H414 | <<locked>> | 90% | 61,801 psi | 89% | 3071 fps | 100% |
| Hodgdon H4350 | <<locked>> | 88% | 60,713 psi | 87% | 3025 fps | 99.9% |
| Hodgdon H4831 | <<locked>> | 98% | 62,076 psi | 89% | 3068 fps | 99.2% |
| Hodgdon H4831 SC | <<locked>> | 98% | 60,785 psi | 87% | 3051 fps | 99.1% |
| Hodgdon Hybrid 100V | <<locked>> | 94% | 60,858 psi | 87% | 2976 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 82% | 61,902 psi | 89% | 3012 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 50,125 psi | 72% | 3064 fps | 99.8% |
| Hodgdon Superformance | <<locked>> | 90% | 62,569 psi | 90% | 3117 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,130 psi | 53% | 1824 fps | 100% |
| Hodgdon VARGET | <<locked>> | 82% | 61,554 psi | 88% | 2966 fps | 100% |
| IMR 4064 | <<locked>> | 84% | 60,843 psi | 87% | 2946 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 82% | 59,480 psi | 85% | 2940 fps | 100% |
| IMR 4350 | <<locked>> | 92% | 60,379 psi | 87% | 2995 fps | 100% |
| IMR 4451 Enduron | <<locked>> | 88% | 60,423 psi | 87% | 2982 fps | 100% |
| IMR 4831 | <<locked>> | 92% | 60,423 psi | 87% | 3002 fps | 100% |
| IMR 4895 | <<locked>> | 82% | 60,843 psi | 87% | 2995 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 96% | 59,393 psi | 85% | 2995 fps | 99% |
| IMR 7828 SSCᴾ | <<locked>> | 100% | 59,335 psi | 85% | 3107 fps | 99.5% |
| Lovex S060 | <<locked>> | 82% | 61,801 psi | 89% | 2920 fps | 100% |
| Lovex S062 | <<locked>> | 84% | 61,583 psi | 88% | 2940 fps | 100% |
| Lovex S065 | <<locked>> | 90% | 61,366 psi | 88% | 2979 fps | 100% |
| Lovex S070 | <<locked>> | 90% | 59,437 psi | 85% | 2982 fps | 100% |
| Lovex S071ᴾ | <<locked>> | 100% | 52,852 psi | 76% | 2897 fps | 100% |
| Norma 201 | <<locked>> | 82% | 62,990 psi | 90% | 2949 fps | 100% |
| Norma 203B | <<locked>> | 84% | 62,511 psi | 90% | 3005 fps | 100% |
| Norma 204 | <<locked>> | 92% | 61,583 psi | 88% | 3061 fps | 99.9% |
| Norma 217ᴾ | <<locked>> | 100% | 37,101 psi | 53% | 2772 fps | 97.8% |
| Norma MRP | <<locked>> | 98% | 61,728 psi | 89% | 3159 fps | 100% |
| Norma URP | <<locked>> | 92% | 62,062 psi | 89% | 3048 fps | 100% |
| Ramshot Big Game | <<locked>> | 82% | 59,654 psi | 86% | 2982 fps | 100% |
| Ramshot Grandᴾ | <<locked>> | 100% | 60,379 psi | 87% | 3130 fps | 99.7% |
| Ramshot Hunter | <<locked>> | 92% | 60,742 psi | 87% | 3058 fps | 100% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 54,636 psi | 78% | 3005 fps | 99.9% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,927 psi | 54% | 1867 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 84% | 60,176 psi | 86% | 2972 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 86% | 61,482 psi | 88% | 3071 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 90% | 60,263 psi | 87% | 3041 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 92% | 61,989 psi | 89% | 3123 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 50,430 psi | 72% | 3058 fps | 100% |
| ReloadSwiss RS 80ᴾ | <<locked>> | 100% | 45,643 psi | 66% | 2943 fps | 96.6% |
| Rottweil R 902 | <<locked>> | 82% | 60,147 psi | 86% | 2904 fps | 100% |
| Rottweil R 903 | <<locked>> | 86% | 61,003 psi | 88% | 2959 fps | 100% |
| Rottweil R 904 | <<locked>> | 96% | 61,830 psi | 89% | 3035 fps | 99.5% |
| Rottweil R 905 | <<locked>> | 96% | 59,495 psi | 85% | 3048 fps | 99.9% |
| Rottweil R 907 | <<locked>> | 88% | 59,335 psi | 85% | 2963 fps | 100% |
| Shooters World Long Rifle | <<locked>> | 90% | 61,366 psi | 88% | 2979 fps | 100% |
| Shooters World Precision | <<locked>> | 84% | 61,583 psi | 88% | 2940 fps | 100% |
| Shooters World SW4350 | <<locked>> | 90% | 59,437 psi | 85% | 2982 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 86% | 62,018 psi | 89% | 3018 fps | 100% |
| SNPE Vectan SP 9 | <<locked>> | 82% | 62,323 psi | 90% | 2982 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 82% | 62,859 psi | 90% | 2858 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 86% | 60,452 psi | 87% | 2815 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 90% | 61,032 psi | 88% | 2933 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 98% | 62,816 psi | 90% | 3097 fps | 100% |
| Somchem S335 | <<locked>> | 82% | 62,859 psi | 90% | 2858 fps | 100% |
| Somchem S355 | <<locked>> | 86% | 60,379 psi | 87% | 2953 fps | 100% |
| Somchem S361 | <<locked>> | 94% | 60,205 psi | 86% | 2976 fps | 98.9% |
| Somchem S365 | <<locked>> | 94% | 62,381 psi | 90% | 3045 fps | 100% |
| Somchem S385 | <<locked>> | 96% | 60,350 psi | 87% | 3022 fps | 100% |
| Vihtavuori N135 | <<locked>> | 82% | 60,568 psi | 87% | 2848 fps | 100% |
| Vihtavuori N140 | <<locked>> | 82% | 60,437 psi | 87% | 2864 fps | 100% |
| Vihtavuori N150 | <<locked>> | 88% | 61,598 psi | 88% | 2917 fps | 100% |
| Vihtavuori N160 | <<locked>> | 90% | 60,365 psi | 87% | 2982 fps | 100% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 59,451 psi | 85% | 2992 fps | 99.9% |
| Vihtavuori N540 | <<locked>> | 84% | 62,308 psi | 90% | 2917 fps | 100% |
| Vihtavuori N550 | <<locked>> | 90% | 59,698 psi | 86% | 2999 fps | 100% |
| Vihtavuori N555 | <<locked>> | 98% | 61,670 psi | 89% | 3068 fps | 100% |
| Vihtavuori N560 | <<locked>> | 98% | 61,496 psi | 88% | 3153 fps | 99.4% |
| Vihtavuori N565ᴾ | <<locked>> | 100% | 53,838 psi | 77% | 3022 fps | 98.7% |
| Vihtavuori N568ᴾ | <<locked>> | 100% | 47,036 psi | 68% | 2953 fps | 96.3% |
| Winchester 6.5 StaBALL | <<locked>> | 90% | 59,828 psi | 86% | 2940 fps | 100% |
| Winchester 760 | <<locked>> | 90% | 62,033 psi | 89% | 3074 fps | 100% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 55,288 psi | 79% | 3130 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 98% | 60,176 psi | 86% | 3015 fps | 99.8% |
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% | 55,129 psi | 79% | 2861 fps | 99.7% |
| Accurate 3100 | <<locked>> | 80% | 33,562 psi | 48% | 2533 fps | 97.7% |
| Accurate 4064 | <<locked>> | 80% | 56,507 psi | 81% | 2848 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 44,106 psi | 63% | 2769 fps | 100% |
| Accurate High Country | 94.7 gr | 82% | 37,623 psi | 54% | 2740 fps | 95.4% |
| Accurate MAGPRO | <<locked>> | 88% | 43,337 psi | 62% | 2851 fps | 95.7% |
| ADI APS 450 | <<locked>> | 80% | 58,798 psi | 84% | 2244 fps | 100% |
| ADI AR 2208 | <<locked>> | 80% | 51,329 psi | 74% | 2825 fps | 100% |
| ADI AR 2209 | <<locked>> | 80% | 36,666 psi | 53% | 2638 fps | 95.9% |
| ADI AR 2213 | <<locked>> | 86% | 39,755 psi | 57% | 2736 fps | 95.5% |
| ADI AR 2217 | <<locked>> | 94% | 38,319 psi | 55% | 2690 fps | 95.1% |
| ADI AR 2225 | <<locked>> | 90% | 30,763 psi | 44% | 2556 fps | 95.4% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 57,638 psi | 83% | 3051 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 80% | 36,956 psi | 53% | 2641 fps | 96.1% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 52,678 psi | 76% | 2851 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 55,898 psi | 80% | 2920 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 41,655 psi | 60% | 2769 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 80% | 47,558 psi | 68% | 2884 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 36,666 psi | 53% | 2638 fps | 96.1% |
| Alliant Reloder-22 | <<locked>> | 82% | 34,954 psi | 50% | 2641 fps | 95.7% |
| Alliant Reloder-23 | <<locked>> | 80% | 31,763 psi | 46% | 2559 fps | 99.8% |
| Alliant Reloder-25 | <<locked>> | 80% | 28,137 psi | 40% | 2470 fps | 96.2% |
| Alliant Reloder-26 | 95.2 gr | 80% | 34,272 psi | 49% | 2694 fps | 99.2% |
| Baschieri & Pellagri 109 | <<locked>> | 94% | 50,386 psi | 72% | 2867 fps | 95.1% |
| Bofors RP15 | <<locked>> | 84% | 34,737 psi | 50% | 2635 fps | 95.4% |
| Bofors RP3 | <<locked>> | 80% | 53,838 psi | 77% | 2871 fps | 100% |
| Bofors RP30 | <<locked>> | 92% | 36,898 psi | 53% | 2723 fps | 95.6% |
| Bofors RP5 | <<locked>> | 82% | 34,954 psi | 50% | 2641 fps | 95.7% |
| Bofors RP7 | <<locked>> | 80% | 46,804 psi | 67% | 2762 fps | 99.1% |
| Hodgdon H1000 | <<locked>> | 90% | 36,796 psi | 53% | 2657 fps | 95.3% |
| Hodgdon H380 | <<locked>> | 80% | 53,708 psi | 77% | 2887 fps | 100% |
| Hodgdon H414 | <<locked>> | 80% | 45,107 psi | 65% | 2808 fps | 99.3% |
| Hodgdon H4350 | <<locked>> | 80% | 47,645 psi | 68% | 2815 fps | 98.8% |
| Hodgdon H4831 | <<locked>> | 86% | 42,250 psi | 61% | 2740 fps | 95.6% |
| Hodgdon H4831 SC | <<locked>> | 86% | 41,553 psi | 60% | 2723 fps | 95.4% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 39,552 psi | 57% | 2654 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 58,117 psi | 83% | 2963 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 86% | 32,808 psi | 47% | 2651 fps | 95% |
| Hodgdon Superformance | <<locked>> | 80% | 44,121 psi | 63% | 2828 fps | 99.1% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,862 psi | 40% | 1631 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 57,943 psi | 83% | 2917 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 54,027 psi | 78% | 2854 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 80% | 56,086 psi | 81% | 2890 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 42,076 psi | 60% | 2694 fps | 98.4% |
| IMR 4451 Enduron | <<locked>> | 80% | 47,819 psi | 69% | 2782 fps | 99.5% |
| IMR 4831 | <<locked>> | 80% | 41,974 psi | 60% | 2717 fps | 100% |
| IMR 4895 | <<locked>> | 80% | 57,290 psi | 82% | 2946 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 84% | 41,466 psi | 60% | 2684 fps | 95.6% |
| IMR 7828 SSC | <<locked>> | 86% | 38,276 psi | 55% | 2717 fps | 95.1% |
| Lovex S060 | <<locked>> | 80% | 58,247 psi | 84% | 2874 fps | 100% |
| Lovex S062 | <<locked>> | 80% | 54,824 psi | 79% | 2851 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 45,905 psi | 66% | 2740 fps | 99.8% |
| Lovex S070 | <<locked>> | 80% | 44,295 psi | 64% | 2733 fps | 99.2% |
| Lovex S071 | <<locked>> | 80% | 29,327 psi | 42% | 2425 fps | 96.2% |
| Norma 201 | <<locked>> | 80% | 59,379 psi | 85% | 2904 fps | 100% |
| Norma 203B | <<locked>> | 80% | 55,288 psi | 79% | 2907 fps | 100% |
| Norma 204 | <<locked>> | 80% | 41,843 psi | 60% | 2733 fps | 97.3% |
| Norma 217 | <<locked>> | 94% | 31,111 psi | 45% | 2608 fps | 95.3% |
| Norma MRP | <<locked>> | 80% | 34,185 psi | 49% | 2654 fps | 96.9% |
| Norma URP | <<locked>> | 80% | 43,004 psi | 62% | 2753 fps | 100% |
| Ramshot Big Game | <<locked>> | 80% | 55,840 psi | 80% | 2930 fps | 100% |
| Ramshot Grand | <<locked>> | 86% | 37,826 psi | 54% | 2717 fps | 95.4% |
| Ramshot Hunter | <<locked>> | 80% | 41,655 psi | 60% | 2746 fps | 99.3% |
| Ramshot Magnum | <<locked>> | 84% | 31,937 psi | 46% | 2549 fps | 95.1% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,529 psi | 41% | 1673 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 53,185 psi | 76% | 2871 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 50,241 psi | 72% | 2923 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 43,555 psi | 63% | 2785 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 41,568 psi | 60% | 2799 fps | 99.9% |
| ReloadSwiss RS 76 | <<locked>> | 86% | 32,010 psi | 46% | 2628 fps | 96% |
| ReloadSwiss RS 80 | <<locked>> | 98% | 42,699 psi | 61% | 2881 fps | 95.8% |
| Rottweil R 902 | <<locked>> | 80% | 56,811 psi | 82% | 2858 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 50,923 psi | 73% | 2822 fps | 100% |
| Rottweil R 904 | <<locked>> | 80% | 38,130 psi | 55% | 2618 fps | 95.1% |
| Rottweil R 905 | <<locked>> | 80% | 36,114 psi | 52% | 2625 fps | 96.1% |
| Rottweil R 907 | <<locked>> | 80% | 46,804 psi | 67% | 2762 fps | 99.1% |
| Shooters World Long Rifle | <<locked>> | 80% | 45,905 psi | 66% | 2740 fps | 99.8% |
| Shooters World Precision | <<locked>> | 80% | 54,824 psi | 79% | 2851 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 44,295 psi | 64% | 2733 fps | 99.2% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 51,401 psi | 74% | 2874 fps | 100% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 58,668 psi | 84% | 2933 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 59,292 psi | 85% | 2815 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 50,720 psi | 73% | 2690 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 44,947 psi | 65% | 2687 fps | 99.2% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 35,781 psi | 51% | 2621 fps | 96% |
| Somchem S335 | <<locked>> | 80% | 59,335 psi | 85% | 2815 fps | 100% |
| Somchem S355 | <<locked>> | 80% | 50,618 psi | 73% | 2815 fps | 100% |
| Somchem S361 | <<locked>> | 82% | 41,365 psi | 59% | 2657 fps | 95.3% |
| Somchem S365 | <<locked>> | 80% | 39,784 psi | 57% | 2713 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 36,898 psi | 53% | 2612 fps | 97.2% |
| Vihtavuori N135 | <<locked>> | 80% | 57,159 psi | 82% | 2805 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 56,869 psi | 82% | 2822 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 48,414 psi | 70% | 2740 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 44,251 psi | 64% | 2740 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 31,995 psi | 46% | 2487 fps | 95% |
| Vihtavuori N540 | <<locked>> | 80% | 55,230 psi | 79% | 2825 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 43,903 psi | 63% | 2753 fps | 100% |
| Vihtavuori N555 | <<locked>> | 80% | 35,621 psi | 51% | 2638 fps | 99.7% |
| Vihtavuori N560 | 97 gr | 84% | 39,088 psi | 56% | 2749 fps | 95% |
| Vihtavuori N565 | <<locked>> | 90% | 39,073 psi | 56% | 2746 fps | 95.5% |
| Vihtavuori N568 | <<locked>> | 98% | 44,106 psi | 63% | 2894 fps | 95.5% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 43,120 psi | 62% | 2700 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 45,237 psi | 65% | 2808 fps | 99.3% |
| Winchester StaBALL HD | <<locked>> | 80% | 28,558 psi | 41% | 2585 fps | 99.9% |
| Winchester Supreme 780 | <<locked>> | 82% | 35,781 psi | 51% | 2585 fps | 95.8% |
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 105 powders for 37 XC loaded with the .375 | 270gr | Barnes X S. Norma MRP delivers the highest muzzle velocity at 3,159 fps; across all powders the maximum-charge window runs from 1,824 fps to 3,159 fps. Accurate 3100 gives the best case fill at 100 %, and 105 of the 105 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 270.0 gr projectile in 0.375" calls for a 1:6.0 twist; slower twists will usually not stabilise this weight. Accurate 3100, ADI AR 2213, ADI AR 2217 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 High Country, Alliant Reloder-26, Vihtavuori N560 rank at the top here: for 37 XC with the .375 | 270gr | Barnes X S 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.