Load Specifications
Load data in caliber .338-378 Weath. Mag. with .338 | 200gr | Peregrine VRG-3 bullet and 70 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Hodgdon Retumbo, ReloadSwiss RS 76 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: 26"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 3100 | <<locked>> | 92% | 54,810 psi | 86% | 3064 fps | 100% |
| Accurate 4350 | <<locked>> | 84% | 55,637 psi | 87% | 3097 fps | 100% |
| Accurate MAGPRO | <<locked>> | 90% | 53,722 psi | 84% | 3163 fps | 98% |
| ADI AR 2209 | <<locked>> | 90% | 56,985 psi | 89% | 3166 fps | 99.7% |
| ADI AR 2213 | <<locked>> | 92% | 54,926 psi | 86% | 3173 fps | 99% |
| ADI AR 2217ᴾ | <<locked>> | 100% | 52,939 psi | 83% | 3127 fps | 99.1% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 47,384 psi | 74% | 3084 fps | 99.9% |
| Alliant Reloder-16 | <<locked>> | 86% | 56,927 psi | 89% | 3163 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 90% | 56,362 psi | 88% | 3153 fps | 99.7% |
| Alliant Reloder-22 | <<locked>> | 92% | 55,056 psi | 86% | 3166 fps | 99.7% |
| Alliant Reloder-23 | <<locked>> | 94% | 56,362 psi | 88% | 3133 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 98% | 56,144 psi | 88% | 3199 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 90% | 57,217 psi | 90% | 3225 fps | 100% |
| Baschieri & Pellagri 109 | <<locked>> | 94% | 56,362 psi | 88% | 3127 fps | 97% |
| Bofors RP15 | <<locked>> | 94% | 54,099 psi | 85% | 3146 fps | 99.5% |
| Bofors RP30ᴾ | <<locked>> | 100% | 55,883 psi | 88% | 3202 fps | 99.5% |
| Bofors RP5 | <<locked>> | 92% | 55,056 psi | 86% | 3166 fps | 99.7% |
| Bofors RP7 | <<locked>> | 84% | 57,696 psi | 90% | 3104 fps | 100% |
| Hodgdon H1000 | <<locked>> | 98% | 54,650 psi | 86% | 3159 fps | 99.6% |
| Hodgdon H414 | <<locked>> | 84% | 57,551 psi | 90% | 3159 fps | 100% |
| Hodgdon H4350 | <<locked>> | 82% | 56,202 psi | 88% | 3117 fps | 99.8% |
| Hodgdon H4831 | <<locked>> | 90% | 54,592 psi | 86% | 3104 fps | 98.5% |
| Hodgdon H4831 SC | <<locked>> | 92% | 57,334 psi | 90% | 3150 fps | 98.8% |
| Hodgdon Hybrid 100V | <<locked>> | 88% | 57,072 psi | 89% | 3074 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 98% | 55,100 psi | 86% | 3281 fps | 100% |
| Hodgdon Superformance | <<locked>> | 82% | 54,273 psi | 85% | 3133 fps | 99.9% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,130 psi | 58% | 1998 fps | 100% |
| IMR 4350 | <<locked>> | 86% | 56,072 psi | 88% | 3087 fps | 99.9% |
| IMR 4451 Enduron | <<locked>> | 82% | 55,593 psi | 87% | 3071 fps | 100% |
| IMR 4831 | <<locked>> | 86% | 56,144 psi | 88% | 3091 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 90% | 55,463 psi | 87% | 3087 fps | 98.7% |
| IMR 7828 SSC | <<locked>> | 94% | 56,753 psi | 89% | 3212 fps | 99.3% |
| IMR 8133 Enduronᴾ | <<locked>> | 100% | 42,714 psi | 67% | 2972 fps | 97% |
| Lovex S065 | <<locked>> | 84% | 56,188 psi | 88% | 3068 fps | 100% |
| Lovex S070 | <<locked>> | 84% | 54,505 psi | 85% | 3061 fps | 100% |
| Lovex S071 | <<locked>> | 98% | 56,101 psi | 88% | 3084 fps | 100% |
| Norma 204 | <<locked>> | 86% | 57,246 psi | 90% | 3150 fps | 99.7% |
| Norma 217ᴾ | <<locked>> | 100% | 43,047 psi | 67% | 3002 fps | 99% |
| Norma MRP | <<locked>> | 90% | 54,882 psi | 86% | 3186 fps | 100% |
| Norma URP | <<locked>> | 84% | 54,143 psi | 85% | 3081 fps | 100% |
| Ramshot Grand | <<locked>> | 92% | 53,505 psi | 84% | 3163 fps | 99.2% |
| Ramshot Hunter | <<locked>> | 86% | 56,855 psi | 89% | 3146 fps | 100% |
| Ramshot Magnum | <<locked>> | 96% | 56,217 psi | 88% | 3156 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,985 psi | 60% | 2044 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 84% | 55,970 psi | 88% | 3123 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 84% | 54,476 psi | 85% | 3153 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 98% | 56,057 psi | 88% | 3271 fps | 100% |
| ReloadSwiss RS 80ᴾ | <<locked>> | 100% | 55,201 psi | 87% | 3222 fps | 98.6% |
| Rottweil R 904 | <<locked>> | 88% | 54,143 psi | 85% | 3074 fps | 98.9% |
| Rottweil R 905 | <<locked>> | 90% | 55,869 psi | 88% | 3140 fps | 99.7% |
| Rottweil R 907 | <<locked>> | 84% | 57,696 psi | 90% | 3104 fps | 100% |
| Shooters World Long Rifle | <<locked>> | 84% | 56,188 psi | 88% | 3068 fps | 100% |
| Shooters World SW4350 | <<locked>> | 84% | 54,505 psi | 85% | 3061 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 84% | 55,419 psi | 87% | 3018 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 90% | 55,448 psi | 87% | 3136 fps | 99.7% |
| Somchem S361 | <<locked>> | 88% | 55,709 psi | 87% | 3061 fps | 98.6% |
| Somchem S365 | <<locked>> | 86% | 54,940 psi | 86% | 3084 fps | 100% |
| Somchem S385 | <<locked>> | 90% | 56,362 psi | 88% | 3110 fps | 99.9% |
| Vihtavuori N150 | <<locked>> | 82% | 56,318 psi | 88% | 3005 fps | 100% |
| Vihtavuori N160 | <<locked>> | 84% | 55,912 psi | 88% | 3074 fps | 100% |
| Vihtavuori N165 | <<locked>> | 94% | 56,101 psi | 88% | 3091 fps | 99.9% |
| Vihtavuori N550 | <<locked>> | 84% | 55,027 psi | 86% | 3077 fps | 100% |
| Vihtavuori N555 | <<locked>> | 90% | 54,665 psi | 86% | 3107 fps | 100% |
| Vihtavuori N560 | <<locked>> | 90% | 54,607 psi | 86% | 3179 fps | 98.7% |
| Vihtavuori N565 | <<locked>> | 96% | 54,882 psi | 86% | 3159 fps | 98.9% |
| Vihtavuori N568ᴾ | <<locked>> | 100% | 55,912 psi | 88% | 3225 fps | 98.2% |
| Winchester 6.5 StaBALL | <<locked>> | 84% | 55,564 psi | 87% | 3022 fps | 100% |
| Winchester 760 | <<locked>> | 84% | 57,696 psi | 90% | 3163 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 94% | 54,998 psi | 86% | 3215 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 92% | 56,550 psi | 89% | 3107 fps | 99.7% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 26"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 3100 | <<locked>> | 80% | 35,984 psi | 56% | 2703 fps | 98.1% |
| Accurate 4350 | <<locked>> | 80% | 48,356 psi | 76% | 2982 fps | 100% |
| Accurate MAGPRO | <<locked>> | 84% | 43,134 psi | 68% | 2953 fps | 95.3% |
| ADI AR 2209 | <<locked>> | 80% | 40,364 psi | 63% | 2851 fps | 96.9% |
| ADI AR 2213 | <<locked>> | 84% | 41,423 psi | 65% | 2904 fps | 96% |
| ADI AR 2217 | <<locked>> | 92% | 40,045 psi | 63% | 2864 fps | 95.9% |
| ADI AR 2225 | <<locked>> | 88% | 31,401 psi | 49% | 2684 fps | 95.5% |
| Alliant Reloder-16 | <<locked>> | 80% | 46,412 psi | 73% | 2989 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 40,379 psi | 63% | 2844 fps | 97% |
| Alliant Reloder-22 | <<locked>> | 80% | 36,129 psi | 57% | 2776 fps | 95.6% |
| Alliant Reloder-23 | <<locked>> | 80% | 34,737 psi | 54% | 2736 fps | 99.9% |
| Alliant Reloder-25 | <<locked>> | 80% | 30,081 psi | 47% | 2638 fps | 96.7% |
| Alliant Reloder-26 | <<locked>> | 80% | 38,624 psi | 61% | 2890 fps | 99.6% |
| Baschieri & Pellagri 109 | <<locked>> | 90% | 49,676 psi | 78% | 3002 fps | 95.4% |
| Bofors RP15 | <<locked>> | 82% | 35,998 psi | 56% | 2772 fps | 95.4% |
| Bofors RP30 | <<locked>> | 90% | 39,189 psi | 61% | 2874 fps | 96% |
| Bofors RP5 | <<locked>> | 80% | 36,129 psi | 57% | 2776 fps | 95.6% |
| Bofors RP7 | <<locked>> | 80% | 50,734 psi | 80% | 2989 fps | 99.6% |
| Hodgdon H1000 | <<locked>> | 88% | 38,218 psi | 60% | 2822 fps | 95.9% |
| Hodgdon H414 | <<locked>> | 80% | 50,096 psi | 79% | 3038 fps | 99.8% |
| Hodgdon H4350 | <<locked>> | 80% | 52,576 psi | 82% | 3054 fps | 99.5% |
| Hodgdon H4831 | <<locked>> | 82% | 41,205 psi | 65% | 2844 fps | 95.2% |
| Hodgdon H4831 SC | <<locked>> | 82% | 40,495 psi | 63% | 2828 fps | 95% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 43,656 psi | 68% | 2861 fps | 100% |
| Hodgdon Retumbo | 99.2 gr | 84% | 33,663 psi | 53% | 2789 fps | 95.1% |
| Hodgdon Superformance | <<locked>> | 80% | 50,328 psi | 79% | 3064 fps | 99.7% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,789 psi | 44% | 1788 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 46,180 psi | 72% | 2913 fps | 99.1% |
| IMR 4451 Enduron | <<locked>> | 80% | 52,214 psi | 82% | 3015 fps | 99.8% |
| IMR 4831 | <<locked>> | 80% | 45,948 psi | 72% | 2923 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 40,074 psi | 63% | 2785 fps | 95% |
| IMR 7828 SSC | <<locked>> | 84% | 39,798 psi | 62% | 2877 fps | 95.5% |
| IMR 8133 Enduron | <<locked>> | 98% | 39,798 psi | 62% | 2907 fps | 96% |
| Lovex S065 | <<locked>> | 80% | 49,487 psi | 78% | 2956 fps | 100% |
| Lovex S070 | <<locked>> | 80% | 47,935 psi | 75% | 2949 fps | 99.6% |
| Lovex S071 | <<locked>> | 80% | 30,792 psi | 48% | 2569 fps | 96.2% |
| Norma 204 | <<locked>> | 80% | 46,543 psi | 73% | 2959 fps | 98.3% |
| Norma 217 | <<locked>> | 92% | 32,343 psi | 51% | 2733 fps | 95.3% |
| Norma MRP | <<locked>> | 80% | 38,072 psi | 60% | 2851 fps | 97.7% |
| Norma URP | <<locked>> | 80% | 47,413 psi | 74% | 2966 fps | 100% |
| Ramshot Grand | <<locked>> | 84% | 39,566 psi | 62% | 2884 fps | 95.9% |
| Ramshot Hunter | <<locked>> | 80% | 46,398 psi | 73% | 2966 fps | 99.8% |
| Ramshot Magnum | <<locked>> | 82% | 32,721 psi | 51% | 2680 fps | 95.2% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,384 psi | 44% | 1831 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 48,573 psi | 76% | 3002 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 46,920 psi | 74% | 3025 fps | 100% |
| ReloadSwiss RS 76 | 106.2 gr | 84% | 32,909 psi | 52% | 2759 fps | 96.2% |
| ReloadSwiss RS 80 | <<locked>> | 94% | 43,511 psi | 68% | 2999 fps | 95.8% |
| Rottweil R 904 | <<locked>> | 80% | 41,626 psi | 65% | 2828 fps | 96.2% |
| Rottweil R 905 | <<locked>> | 80% | 39,682 psi | 62% | 2828 fps | 96.9% |
| Rottweil R 907 | <<locked>> | 80% | 50,734 psi | 80% | 2989 fps | 99.6% |
| Shooters World Long Rifle | <<locked>> | 80% | 49,487 psi | 78% | 2956 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 47,935 psi | 75% | 2949 fps | 99.6% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 48,530 psi | 76% | 2900 fps | 99.6% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 39,349 psi | 62% | 2822 fps | 96.8% |
| Somchem S361 | <<locked>> | 80% | 42,380 psi | 66% | 2815 fps | 95.6% |
| Somchem S365 | <<locked>> | 80% | 44,585 psi | 70% | 2920 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 40,161 psi | 63% | 2808 fps | 97.8% |
| Vihtavuori N150 | <<locked>> | 80% | 52,765 psi | 83% | 2953 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 48,863 psi | 77% | 2959 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 34,795 psi | 55% | 2671 fps | 95.8% |
| Vihtavuori N550 | <<locked>> | 80% | 48,124 psi | 75% | 2963 fps | 100% |
| Vihtavuori N555 | <<locked>> | 80% | 38,856 psi | 61% | 2818 fps | 99.8% |
| Vihtavuori N560 | 100.5 gr | 82% | 41,002 psi | 64% | 2907 fps | 95.3% |
| Vihtavuori N565 | <<locked>> | 88% | 41,350 psi | 65% | 2897 fps | 95.8% |
| Vihtavuori N568 | <<locked>> | 94% | 44,730 psi | 70% | 3012 fps | 95.5% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 48,167 psi | 75% | 2913 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 50,227 psi | 79% | 3038 fps | 99.8% |
| Winchester StaBALL HD | <<locked>> | 80% | 31,270 psi | 49% | 2759 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 36,738 psi | 58% | 2723 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 75 powders for .338-378 Weath. Mag. loaded with the .338 | 200gr | Peregrine VRG-3. Hodgdon Retumbo delivers the highest muzzle velocity at 3,281 fps; across all powders the maximum-charge window runs from 1,998 fps to 3,281 fps. ADI AR 2217 gives the best case fill at 100 %, and 75 of the 75 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (440 MPa), the top charges use 58–90 %, leaving at least 10 % headroom. The 200.0 gr projectile in 0.338" calls for a 1:15.5 twist; slower twists will usually not stabilise this weight. ADI AR 2217, ADI AR 2218, 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. Hodgdon Retumbo, ReloadSwiss RS 76, Vihtavuori N560 rank at the top here: for .338-378 Weath. Mag. with the .338 | 200gr | Peregrine VRG-3 they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, ADI AR 2218, IMR 7977 Enduron, Vihtavuori N170 burn incompletely and react more sensitively to barrel length and temperature. Always begin at the start load and work up in small increments while checking case and primer for pressure signs.