Load Specifications
Bullet Manufacturer:Impala Bullets
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 | Impala RNFP KO bullet and 101 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Alliant Reloder-26, Vihtavuori N560 and Norma MRP.
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% | 62,845 psi | 90% | 2969 fps | 100% |
| Accurate 3100 | <<locked>> | 98% | 59,625 psi | 86% | 2992 fps | 100% |
| Accurate 4064 | <<locked>> | 82% | 60,336 psi | 87% | 2900 fps | 100% |
| Accurate 4350 | <<locked>> | 90% | 61,221 psi | 88% | 3028 fps | 100% |
| Accurate MAGPRO | <<locked>> | 98% | 61,163 psi | 88% | 3153 fps | 99.1% |
| ADI APS 450 | <<locked>> | 84% | 62,845 psi | 90% | 2306 fps | 100% |
| ADI AR 2208 | <<locked>> | 86% | 61,569 psi | 88% | 2976 fps | 100% |
| ADI AR 2209 | <<locked>> | 96% | 60,843 psi | 87% | 3081 fps | 99.9% |
| ADI AR 2213ᴾ | <<locked>> | 100% | 62,584 psi | 90% | 3146 fps | 99.7% |
| ADI AR 2217ᴾ | <<locked>> | 100% | 46,470 psi | 67% | 2871 fps | 97.8% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 41,597 psi | 60% | 2848 fps | 99.4% |
| Alliant Power Pro 2000-MR | <<locked>> | 82% | 62,395 psi | 90% | 3117 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 96% | 61,090 psi | 88% | 3077 fps | 99.9% |
| Alliant Reloder- TS 15.5 | <<locked>> | 84% | 59,712 psi | 86% | 2953 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 82% | 59,828 psi | 86% | 2979 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 92% | 60,829 psi | 87% | 3074 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 88% | 62,714 psi | 90% | 3094 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 96% | 60,321 psi | 87% | 3071 fps | 99.9% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 62,221 psi | 89% | 3140 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 59,379 psi | 85% | 3048 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 51,576 psi | 74% | 3012 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 96% | 60,292 psi | 87% | 3156 fps | 100% |
| Baschieri & Pellagri 109ᴾ | <<locked>> | 100% | 60,481 psi | 87% | 3038 fps | 97.4% |
| Bofors RP15ᴾ | <<locked>> | 100% | 57,319 psi | 82% | 3071 fps | 99.8% |
| Bofors RP3 | <<locked>> | 84% | 61,308 psi | 88% | 2972 fps | 100% |
| Bofors RP30ᴾ | <<locked>> | 100% | 47,761 psi | 69% | 2953 fps | 98.5% |
| Bofors RP5ᴾ | <<locked>> | 100% | 62,221 psi | 89% | 3140 fps | 100% |
| Bofors RP7 | <<locked>> | 88% | 59,770 psi | 86% | 2972 fps | 100% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 50,894 psi | 73% | 2956 fps | 99.1% |
| Hodgdon H380 | <<locked>> | 84% | 61,250 psi | 88% | 2999 fps | 100% |
| Hodgdon H414 | <<locked>> | 90% | 62,265 psi | 89% | 3081 fps | 100% |
| Hodgdon H4350 | <<locked>> | 88% | 61,293 psi | 88% | 3035 fps | 99.9% |
| Hodgdon H4831 | <<locked>> | 98% | 62,714 psi | 90% | 3081 fps | 99.3% |
| Hodgdon H4831 SC | <<locked>> | 98% | 61,279 psi | 88% | 3061 fps | 99.2% |
| Hodgdon Hybrid 100V | <<locked>> | 94% | 61,511 psi | 88% | 2986 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 82% | 62,395 psi | 90% | 3018 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 50,546 psi | 73% | 3074 fps | 99.9% |
| Hodgdon Superformance | <<locked>> | 88% | 58,972 psi | 85% | 3071 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,144 psi | 53% | 1827 fps | 100% |
| Hodgdon VARGET | <<locked>> | 82% | 62,076 psi | 89% | 2972 fps | 100% |
| IMR 4064 | <<locked>> | 84% | 61,337 psi | 88% | 2956 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 82% | 59,944 psi | 86% | 2949 fps | 100% |
| IMR 4350 | <<locked>> | 92% | 60,756 psi | 87% | 3005 fps | 100% |
| IMR 4451 Enduron | <<locked>> | 88% | 60,814 psi | 87% | 2989 fps | 100% |
| IMR 4831 | <<locked>> | 92% | 61,003 psi | 88% | 3012 fps | 100% |
| IMR 4895 | <<locked>> | 82% | 61,395 psi | 88% | 3005 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 96% | 59,770 psi | 86% | 3005 fps | 99.1% |
| IMR 7828 SSCᴾ | <<locked>> | 100% | 60,060 psi | 86% | 3123 fps | 99.6% |
| Lovex S060 | <<locked>> | 82% | 62,149 psi | 89% | 2930 fps | 100% |
| Lovex S062 | <<locked>> | 84% | 62,120 psi | 89% | 2949 fps | 100% |
| Lovex S065 | <<locked>> | 90% | 61,757 psi | 89% | 2989 fps | 100% |
| Lovex S070 | <<locked>> | 90% | 59,901 psi | 86% | 2989 fps | 100% |
| Lovex S071ᴾ | <<locked>> | 100% | 53,359 psi | 77% | 2907 fps | 100% |
| Norma 203B | <<locked>> | 84% | 62,787 psi | 90% | 3012 fps | 100% |
| Norma 204 | <<locked>> | 92% | 62,062 psi | 89% | 3071 fps | 99.9% |
| Norma 217ᴾ | <<locked>> | 100% | 37,478 psi | 54% | 2785 fps | 98% |
| Norma MRP | <<locked>> | 98% | 62,294 psi | 89% | 3169 fps | 100% |
| Norma URP | <<locked>> | 92% | 62,555 psi | 90% | 3054 fps | 100% |
| Ramshot Big Game | <<locked>> | 82% | 60,104 psi | 86% | 2989 fps | 100% |
| Ramshot Grandᴾ | <<locked>> | 100% | 61,148 psi | 88% | 3143 fps | 99.8% |
| Ramshot Hunter | <<locked>> | 92% | 61,322 psi | 88% | 3068 fps | 100% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 55,259 psi | 79% | 3018 fps | 99.9% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,927 psi | 54% | 1873 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 84% | 60,582 psi | 87% | 2982 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 86% | 62,178 psi | 89% | 3081 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 90% | 60,655 psi | 87% | 3051 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 92% | 62,700 psi | 90% | 3136 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 50,981 psi | 73% | 3071 fps | 100% |
| ReloadSwiss RS 80ᴾ | <<locked>> | 100% | 46,209 psi | 66% | 2956 fps | 96.9% |
| Rottweil R 902 | <<locked>> | 82% | 60,495 psi | 87% | 2910 fps | 100% |
| Rottweil R 903 | <<locked>> | 86% | 61,511 psi | 88% | 2969 fps | 100% |
| Rottweil R 904 | <<locked>> | 96% | 62,381 psi | 90% | 3045 fps | 99.6% |
| Rottweil R 905 | <<locked>> | 96% | 59,988 psi | 86% | 3061 fps | 99.9% |
| Rottweil R 907 | <<locked>> | 88% | 59,770 psi | 86% | 2972 fps | 100% |
| Shooters World Long Rifle | <<locked>> | 90% | 61,757 psi | 89% | 2989 fps | 100% |
| Shooters World Precision | <<locked>> | 84% | 62,120 psi | 89% | 2949 fps | 100% |
| Shooters World SW4350 | <<locked>> | 90% | 59,901 psi | 86% | 2989 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 86% | 62,497 psi | 90% | 3028 fps | 100% |
| SNPE Vectan SP 9 | <<locked>> | 82% | 62,787 psi | 90% | 2992 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 86% | 60,785 psi | 87% | 2822 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 90% | 61,351 psi | 88% | 2943 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 96% | 59,495 psi | 85% | 3054 fps | 99.9% |
| Somchem S355 | <<locked>> | 86% | 60,887 psi | 87% | 2963 fps | 100% |
| Somchem S361 | <<locked>> | 94% | 60,611 psi | 87% | 2982 fps | 99% |
| Somchem S365 | <<locked>> | 94% | 62,874 psi | 90% | 3051 fps | 100% |
| Somchem S385 | <<locked>> | 96% | 60,887 psi | 87% | 3028 fps | 100% |
| Vihtavuori N135 | <<locked>> | 82% | 61,017 psi | 88% | 2854 fps | 100% |
| Vihtavuori N140 | <<locked>> | 82% | 60,756 psi | 87% | 2874 fps | 100% |
| Vihtavuori N150 | <<locked>> | 88% | 62,033 psi | 89% | 2927 fps | 100% |
| Vihtavuori N160 | <<locked>> | 90% | 60,771 psi | 87% | 2992 fps | 100% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 60,031 psi | 86% | 3002 fps | 100% |
| Vihtavuori N540 | <<locked>> | 84% | 62,743 psi | 90% | 2923 fps | 100% |
| Vihtavuori N550 | <<locked>> | 90% | 60,104 psi | 86% | 3005 fps | 100% |
| Vihtavuori N555 | <<locked>> | 98% | 62,308 psi | 90% | 3077 fps | 100% |
| Vihtavuori N560 | <<locked>> | 98% | 62,091 psi | 89% | 3166 fps | 99.5% |
| Vihtavuori N565ᴾ | <<locked>> | 100% | 54,317 psi | 78% | 3031 fps | 98.9% |
| Vihtavuori N568ᴾ | <<locked>> | 100% | 47,442 psi | 68% | 2963 fps | 96.5% |
| Winchester 6.5 StaBALL | <<locked>> | 90% | 60,350 psi | 87% | 2949 fps | 100% |
| Winchester 760 | <<locked>> | 90% | 62,584 psi | 90% | 3084 fps | 100% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 55,912 psi | 80% | 3140 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 98% | 60,655 psi | 87% | 3025 fps | 99.9% |
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% | 55,405 psi | 80% | 2867 fps | 99.8% |
| Accurate 3100 | <<locked>> | 80% | 33,924 psi | 49% | 2546 fps | 97.9% |
| Accurate 4064 | <<locked>> | 80% | 56,855 psi | 82% | 2854 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 44,585 psi | 64% | 2779 fps | 100% |
| Accurate MAGPRO | <<locked>> | 86% | 40,988 psi | 59% | 2802 fps | 95.1% |
| ADI APS 450 | <<locked>> | 80% | 58,842 psi | 85% | 2251 fps | 100% |
| ADI AR 2208 | <<locked>> | 80% | 51,634 psi | 74% | 2835 fps | 100% |
| ADI AR 2209 | <<locked>> | 80% | 37,028 psi | 53% | 2648 fps | 96.1% |
| ADI AR 2213 | <<locked>> | 86% | 40,074 psi | 58% | 2746 fps | 95.7% |
| ADI AR 2217 | <<locked>> | 94% | 38,551 psi | 55% | 2700 fps | 95.3% |
| ADI AR 2225 | <<locked>> | 90% | 31,053 psi | 45% | 2569 fps | 95.7% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 58,175 psi | 84% | 3064 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 80% | 37,362 psi | 54% | 2654 fps | 96.3% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 53,026 psi | 76% | 2858 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 56,420 psi | 81% | 2930 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 41,989 psi | 60% | 2776 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 80% | 47,892 psi | 69% | 2890 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 37,028 psi | 53% | 2651 fps | 96.3% |
| Alliant Reloder-22 | <<locked>> | 80% | 33,141 psi | 48% | 2595 fps | 95% |
| Alliant Reloder-23 | <<locked>> | 80% | 32,068 psi | 46% | 2569 fps | 99.8% |
| Alliant Reloder-25 | <<locked>> | 80% | 28,413 psi | 41% | 2484 fps | 96.4% |
| Alliant Reloder-26 | 96 gr | 80% | 34,621 psi | 50% | 2707 fps | 99.3% |
| Baschieri & Pellagri 109 | <<locked>> | 94% | 50,705 psi | 73% | 2877 fps | 95.3% |
| Bofors RP15 | <<locked>> | 84% | 35,114 psi | 50% | 2644 fps | 95.6% |
| Bofors RP3 | <<locked>> | 80% | 54,157 psi | 78% | 2877 fps | 100% |
| Bofors RP30 | <<locked>> | 92% | 37,318 psi | 54% | 2736 fps | 95.8% |
| Bofors RP5 | <<locked>> | 80% | 33,141 psi | 48% | 2595 fps | 95% |
| Bofors RP7 | <<locked>> | 80% | 47,137 psi | 68% | 2772 fps | 99.2% |
| Hodgdon H1000 | <<locked>> | 90% | 37,072 psi | 53% | 2671 fps | 95.5% |
| Hodgdon H380 | <<locked>> | 80% | 53,998 psi | 78% | 2897 fps | 100% |
| Hodgdon H414 | <<locked>> | 80% | 45,542 psi | 65% | 2818 fps | 99.4% |
| Hodgdon H4350 | <<locked>> | 80% | 47,935 psi | 69% | 2825 fps | 98.9% |
| Hodgdon H4831 | <<locked>> | 84% | 40,089 psi | 58% | 2694 fps | 95% |
| Hodgdon H4831 SC | <<locked>> | 86% | 41,901 psi | 60% | 2733 fps | 95.6% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 39,987 psi | 57% | 2664 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 58,494 psi | 84% | 2969 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 86% | 33,098 psi | 48% | 2664 fps | 95.3% |
| Hodgdon Superformance | <<locked>> | 80% | 44,570 psi | 64% | 2841 fps | 99.2% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,949 psi | 40% | 1637 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 58,450 psi | 84% | 2927 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 54,346 psi | 78% | 2861 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 80% | 56,318 psi | 81% | 2897 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 42,496 psi | 61% | 2703 fps | 98.5% |
| IMR 4451 Enduron | <<locked>> | 80% | 48,080 psi | 69% | 2792 fps | 99.5% |
| IMR 4831 | <<locked>> | 80% | 42,308 psi | 61% | 2723 fps | 100% |
| IMR 4895 | <<locked>> | 80% | 57,812 psi | 83% | 2956 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 82% | 39,407 psi | 57% | 2641 fps | 95% |
| IMR 7828 SSC | <<locked>> | 86% | 38,609 psi | 55% | 2726 fps | 95.3% |
| Lovex S060 | <<locked>> | 80% | 58,552 psi | 84% | 2884 fps | 100% |
| Lovex S062 | <<locked>> | 80% | 55,187 psi | 79% | 2858 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 46,180 psi | 66% | 2749 fps | 99.9% |
| Lovex S070 | <<locked>> | 80% | 44,614 psi | 64% | 2743 fps | 99.3% |
| Lovex S071 | <<locked>> | 80% | 29,602 psi | 43% | 2434 fps | 96.4% |
| Norma 203B | <<locked>> | 80% | 55,796 psi | 80% | 2917 fps | 100% |
| Norma 204 | <<locked>> | 80% | 42,235 psi | 61% | 2740 fps | 97.5% |
| Norma 217 | <<locked>> | 94% | 31,415 psi | 45% | 2621 fps | 95.6% |
| Norma MRP | 93.1 gr | 80% | 34,447 psi | 49% | 2664 fps | 97.1% |
| Norma URP | <<locked>> | 80% | 43,352 psi | 62% | 2762 fps | 100% |
| Ramshot Big Game | <<locked>> | 80% | 56,304 psi | 81% | 2940 fps | 100% |
| Ramshot Grand | <<locked>> | 86% | 38,203 psi | 55% | 2730 fps | 95.6% |
| Ramshot Hunter | <<locked>> | 80% | 42,061 psi | 60% | 2756 fps | 99.4% |
| Ramshot Magnum | <<locked>> | 84% | 32,256 psi | 46% | 2562 fps | 95.4% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,601 psi | 41% | 1677 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 53,606 psi | 77% | 2881 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 50,589 psi | 73% | 2930 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 43,888 psi | 63% | 2795 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 41,959 psi | 60% | 2808 fps | 99.9% |
| ReloadSwiss RS 76 | <<locked>> | 84% | 30,385 psi | 44% | 2582 fps | 95.2% |
| ReloadSwiss RS 80 | <<locked>> | 96% | 40,393 psi | 58% | 2831 fps | 95% |
| Rottweil R 902 | <<locked>> | 80% | 57,174 psi | 82% | 2867 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 51,256 psi | 74% | 2831 fps | 100% |
| Rottweil R 904 | <<locked>> | 80% | 38,392 psi | 55% | 2625 fps | 95.3% |
| Rottweil R 905 | <<locked>> | 80% | 36,419 psi | 52% | 2635 fps | 96.3% |
| Rottweil R 907 | <<locked>> | 80% | 47,137 psi | 68% | 2772 fps | 99.2% |
| Shooters World Long Rifle | <<locked>> | 80% | 46,180 psi | 66% | 2749 fps | 99.9% |
| Shooters World Precision | <<locked>> | 80% | 55,187 psi | 79% | 2858 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 44,614 psi | 64% | 2743 fps | 99.3% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 51,822 psi | 74% | 2881 fps | 100% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 59,088 psi | 85% | 2943 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 51,053 psi | 73% | 2697 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 45,324 psi | 65% | 2697 fps | 99.3% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 36,085 psi | 52% | 2631 fps | 96.1% |
| Somchem S355 | <<locked>> | 80% | 50,966 psi | 73% | 2822 fps | 100% |
| Somchem S361 | <<locked>> | 82% | 41,684 psi | 60% | 2667 fps | 95.5% |
| Somchem S365 | <<locked>> | 80% | 40,219 psi | 58% | 2723 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 37,217 psi | 53% | 2621 fps | 97.3% |
| Vihtavuori N135 | <<locked>> | 80% | 57,566 psi | 83% | 2812 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 57,246 psi | 82% | 2828 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 48,762 psi | 70% | 2746 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 44,686 psi | 64% | 2749 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 32,300 psi | 46% | 2497 fps | 95.2% |
| Vihtavuori N540 | <<locked>> | 80% | 55,506 psi | 80% | 2831 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 44,237 psi | 64% | 2762 fps | 100% |
| Vihtavuori N555 | <<locked>> | 80% | 35,940 psi | 52% | 2644 fps | 99.7% |
| Vihtavuori N560 | 97.8 gr | 84% | 39,465 psi | 57% | 2762 fps | 95.2% |
| Vihtavuori N565 | <<locked>> | 90% | 39,523 psi | 57% | 2756 fps | 95.7% |
| Vihtavuori N568 | <<locked>> | 98% | 44,527 psi | 64% | 2904 fps | 95.7% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 43,482 psi | 62% | 2710 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 45,672 psi | 66% | 2822 fps | 99.4% |
| Winchester StaBALL HD | <<locked>> | 80% | 28,834 psi | 41% | 2598 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 33,823 psi | 49% | 2539 fps | 95.1% |
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 101 powders for 37 XC loaded with the .375 | 270gr | Impala RNFP KO. Norma MRP delivers the highest muzzle velocity at 3,169 fps; across all powders the maximum-charge window runs from 1,827 fps to 3,169 fps. ADI AR 2213 gives the best case fill at 100 %, and 101 of the 101 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. ADI AR 2213, ADI AR 2217, ADI AR 2225 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 Reloder-26, Vihtavuori N560, Norma MRP rank at the top here: for 37 XC with the .375 | 270gr | Impala RNFP KO 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.