Load Specifications
Load data in caliber .338 Norma Mag. with .338 | 300gr | MAKER Expanding Subsonic bullet and 73 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 Winchester StaBALL HD.
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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You can find more information in our FAQ: How can I use the Personalized Load Calculator?
Max Load - Barrel Length: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 3100 | <<locked>> | 92% | 54,984 psi | 86% | 2415 fps | 100% |
| Accurate 4350 | <<locked>> | 84% | 56,144 psi | 88% | 2428 fps | 100% |
| Accurate MAGPRO | <<locked>> | 92% | 57,334 psi | 90% | 2559 fps | 99.5% |
| ADI AR 2209 | <<locked>> | 90% | 56,898 psi | 89% | 2490 fps | 100% |
| ADI AR 2213 | <<locked>> | 92% | 54,534 psi | 85% | 2500 fps | 99.8% |
| ADI AR 2217ᴾ | <<locked>> | 100% | 52,388 psi | 82% | 2474 fps | 99.8% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 46,905 psi | 74% | 2448 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 86% | 57,116 psi | 90% | 2470 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 90% | 56,376 psi | 88% | 2480 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 92% | 54,752 psi | 86% | 2497 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 94% | 56,333 psi | 88% | 2461 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 98% | 55,535 psi | 87% | 2523 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 90% | 56,652 psi | 89% | 2543 fps | 100% |
| Alliant Reloder-33ᴾ | <<locked>> | 100% | 48,660 psi | 76% | 2493 fps | 96.9% |
| Baschieri & Pellagri 109 | <<locked>> | 94% | 55,898 psi | 88% | 2470 fps | 98.2% |
| Bofors RP15 | <<locked>> | 96% | 57,566 psi | 90% | 2533 fps | 100% |
| Bofors RP30ᴾ | <<locked>> | 100% | 55,071 psi | 86% | 2533 fps | 99.9% |
| Bofors RP5 | <<locked>> | 92% | 54,752 psi | 86% | 2497 fps | 100% |
| Bofors RP7 | <<locked>> | 82% | 54,679 psi | 86% | 2385 fps | 100% |
| Hodgdon H1000 | <<locked>> | 98% | 54,070 psi | 85% | 2493 fps | 100% |
| Hodgdon H414 | <<locked>> | 82% | 54,186 psi | 85% | 2434 fps | 100% |
| Hodgdon H4350 | <<locked>> | 82% | 56,536 psi | 89% | 2441 fps | 100% |
| Hodgdon H4831 | <<locked>> | 90% | 54,389 psi | 85% | 2444 fps | 99.4% |
| Hodgdon H4831 SC | <<locked>> | 92% | 56,956 psi | 89% | 2480 fps | 99.6% |
| Hodgdon Hybrid 100V | <<locked>> | 88% | 57,406 psi | 90% | 2405 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 98% | 54,447 psi | 85% | 2595 fps | 100% |
| Hodgdon Superformance | <<locked>> | 82% | 54,259 psi | 85% | 2467 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,347 psi | 59% | 1493 fps | 100% |
| IMR 4350 | <<locked>> | 86% | 56,217 psi | 88% | 2418 fps | 100% |
| IMR 4451 Enduron | <<locked>> | 82% | 55,898 psi | 88% | 2398 fps | 100% |
| IMR 4831 | <<locked>> | 86% | 56,565 psi | 89% | 2421 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 90% | 55,390 psi | 87% | 2428 fps | 99.5% |
| IMR 7828 SSC | <<locked>> | 94% | 56,333 psi | 88% | 2533 fps | 99.9% |
| IMR 8133 Enduronᴾ | <<locked>> | 100% | 42,525 psi | 67% | 2372 fps | 98.6% |
| Lovex S065 | <<locked>> | 84% | 56,768 psi | 89% | 2398 fps | 100% |
| Lovex S070 | <<locked>> | 84% | 55,100 psi | 86% | 2402 fps | 100% |
| Lovex S071 | <<locked>> | 98% | 56,289 psi | 88% | 2428 fps | 100% |
| Norma 204 | <<locked>> | 86% | 57,319 psi | 90% | 2474 fps | 100% |
| Norma 217ᴾ | <<locked>> | 100% | 42,873 psi | 67% | 2392 fps | 99.9% |
| Norma MRP | <<locked>> | 90% | 54,665 psi | 86% | 2513 fps | 100% |
| Norma URP | <<locked>> | 84% | 54,650 psi | 86% | 2415 fps | 100% |
| Ramshot Grand | <<locked>> | 94% | 57,203 psi | 90% | 2552 fps | 100% |
| Ramshot Hunter | <<locked>> | 86% | 56,956 psi | 89% | 2470 fps | 100% |
| Ramshot Magnum | <<locked>> | 96% | 55,521 psi | 87% | 2493 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 38,334 psi | 60% | 1529 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 84% | 56,130 psi | 88% | 2451 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 84% | 54,563 psi | 86% | 2477 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 98% | 54,781 psi | 86% | 2589 fps | 100% |
| ReloadSwiss RS 80ᴾ | <<locked>> | 100% | 53,809 psi | 84% | 2559 fps | 99.4% |
| Rottweil R 904 | <<locked>> | 88% | 54,418 psi | 85% | 2415 fps | 99.7% |
| Rottweil R 905 | <<locked>> | 90% | 55,927 psi | 88% | 2470 fps | 100% |
| Rottweil R 907 | <<locked>> | 82% | 54,679 psi | 86% | 2385 fps | 100% |
| Shooters World Long Rifle | <<locked>> | 84% | 56,768 psi | 89% | 2398 fps | 100% |
| Shooters World SW4350 | <<locked>> | 84% | 55,100 psi | 86% | 2402 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 84% | 55,840 psi | 88% | 2362 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 90% | 55,492 psi | 87% | 2467 fps | 100% |
| Somchem S361 | <<locked>> | 88% | 55,695 psi | 87% | 2411 fps | 99.4% |
| Somchem S365 | <<locked>> | 86% | 55,187 psi | 86% | 2415 fps | 100% |
| Somchem S385 | <<locked>> | 90% | 56,362 psi | 88% | 2444 fps | 100% |
| Vihtavuori N150 | <<locked>> | 82% | 56,797 psi | 89% | 2343 fps | 100% |
| Vihtavuori N160 | <<locked>> | 84% | 56,159 psi | 88% | 2402 fps | 100% |
| Vihtavuori N165 | <<locked>> | 94% | 55,999 psi | 88% | 2431 fps | 100% |
| Vihtavuori N170 | <<locked>> | 98% | 54,549 psi | 85% | 2448 fps | 96.3% |
| Vihtavuori N550 | <<locked>> | 84% | 55,390 psi | 87% | 2411 fps | 100% |
| Vihtavuori N555 | <<locked>> | 90% | 54,911 psi | 86% | 2441 fps | 100% |
| Vihtavuori N560 | <<locked>> | 90% | 54,433 psi | 85% | 2513 fps | 99.6% |
| Vihtavuori N565 | <<locked>> | 96% | 54,462 psi | 85% | 2503 fps | 99.7% |
| Vihtavuori N568ᴾ | <<locked>> | 100% | 54,969 psi | 86% | 2562 fps | 99.2% |
| Vihtavuori N570ᴾ | <<locked>> | 100% | 51,822 psi | 81% | 2556 fps | 97.3% |
| Winchester 6.5 StaBALL | <<locked>> | 84% | 55,376 psi | 87% | 2365 fps | 100% |
| Winchester 760 | <<locked>> | 82% | 54,186 psi | 85% | 2434 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 94% | 54,462 psi | 85% | 2539 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 92% | 56,260 psi | 88% | 2448 fps | 100% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 3100 | <<locked>> | 80% | 36,999 psi | 58% | 2146 fps | 99.5% |
| Accurate 4350 | <<locked>> | 80% | 49,284 psi | 77% | 2339 fps | 100% |
| Accurate MAGPRO | <<locked>> | 80% | 37,710 psi | 59% | 2241 fps | 95.7% |
| ADI AR 2209 | <<locked>> | 80% | 40,930 psi | 64% | 2251 fps | 98.7% |
| ADI AR 2213 | <<locked>> | 80% | 36,535 psi | 57% | 2198 fps | 96.4% |
| ADI AR 2217 | <<locked>> | 86% | 33,083 psi | 52% | 2126 fps | 95.3% |
| ADI AR 2225 | <<locked>> | 82% | 26,368 psi | 41% | 2001 fps | 95.2% |
| Alliant Reloder-16 | <<locked>> | 80% | 47,137 psi | 74% | 2343 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 41,031 psi | 64% | 2247 fps | 98.7% |
| Alliant Reloder-22 | <<locked>> | 80% | 36,825 psi | 58% | 2205 fps | 97.9% |
| Alliant Reloder-23 | <<locked>> | 80% | 35,592 psi | 56% | 2165 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 30,835 psi | 48% | 2106 fps | 99% |
| Alliant Reloder-26 | <<locked>> | 80% | 39,117 psi | 61% | 2293 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 96% | 42,076 psi | 66% | 2379 fps | 95% |
| Baschieri & Pellagri 109 | <<locked>> | 86% | 43,801 psi | 69% | 2277 fps | 95.5% |
| Bofors RP15 | <<locked>> | 80% | 34,287 psi | 54% | 2152 fps | 97% |
| Bofors RP30 | <<locked>> | 84% | 32,242 psi | 51% | 2142 fps | 95.6% |
| Bofors RP5 | <<locked>> | 80% | 36,825 psi | 58% | 2205 fps | 97.9% |
| Bofors RP7 | <<locked>> | 80% | 51,329 psi | 80% | 2339 fps | 100% |
| Hodgdon H1000 | <<locked>> | 82% | 31,517 psi | 49% | 2090 fps | 95.3% |
| Hodgdon H414 | <<locked>> | 80% | 50,618 psi | 79% | 2385 fps | 100% |
| Hodgdon H4350 | <<locked>> | 80% | 53,069 psi | 83% | 2395 fps | 100% |
| Hodgdon H4831 | <<locked>> | 80% | 38,914 psi | 61% | 2198 fps | 96.5% |
| Hodgdon H4831 SC | <<locked>> | 80% | 38,319 psi | 60% | 2188 fps | 96.4% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 44,527 psi | 70% | 2241 fps | 100% |
| Hodgdon Retumbo | 67.8 gr | 80% | 30,095 psi | 47% | 2126 fps | 96.1% |
| Hodgdon Superformance | <<locked>> | 80% | 50,430 psi | 79% | 2415 fps | 100% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,992 psi | 44% | 1329 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 46,731 psi | 73% | 2287 fps | 99.9% |
| IMR 4451 Enduron | <<locked>> | 80% | 52,707 psi | 83% | 2356 fps | 100% |
| IMR 4831 | <<locked>> | 80% | 46,630 psi | 73% | 2293 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 40,625 psi | 64% | 2198 fps | 97.2% |
| IMR 7828 SSC | <<locked>> | 80% | 35,317 psi | 55% | 2182 fps | 96.1% |
| IMR 8133 Enduron | <<locked>> | 92% | 32,779 psi | 51% | 2175 fps | 95.6% |
| Lovex S065 | <<locked>> | 80% | 50,270 psi | 79% | 2313 fps | 100% |
| Lovex S070 | <<locked>> | 80% | 48,544 psi | 76% | 2313 fps | 100% |
| Lovex S071 | <<locked>> | 80% | 31,966 psi | 50% | 2044 fps | 98.6% |
| Norma 204 | <<locked>> | 80% | 46,978 psi | 74% | 2329 fps | 99.5% |
| Norma 217 | <<locked>> | 86% | 27,021 psi | 42% | 2047 fps | 95.1% |
| Norma MRP | <<locked>> | 80% | 38,609 psi | 61% | 2264 fps | 99.3% |
| Norma URP | <<locked>> | 80% | 47,979 psi | 75% | 2326 fps | 100% |
| Ramshot Grand | <<locked>> | 80% | 34,751 psi | 54% | 2185 fps | 96.3% |
| Ramshot Hunter | <<locked>> | 80% | 46,891 psi | 73% | 2333 fps | 100% |
| Ramshot Magnum | <<locked>> | 80% | 30,980 psi | 49% | 2087 fps | 96.8% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,776 psi | 45% | 1365 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 49,124 psi | 77% | 2362 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 47,297 psi | 74% | 2382 fps | 100% |
| ReloadSwiss RS 76 | 72.6 gr | 80% | 29,008 psi | 45% | 2103 fps | 96.8% |
| ReloadSwiss RS 80 | <<locked>> | 90% | 37,101 psi | 58% | 2280 fps | 95.8% |
| Rottweil R 904 | <<locked>> | 80% | 42,192 psi | 66% | 2228 fps | 98% |
| Rottweil R 905 | <<locked>> | 80% | 40,480 psi | 63% | 2238 fps | 98.8% |
| Rottweil R 907 | <<locked>> | 80% | 51,329 psi | 80% | 2339 fps | 100% |
| Shooters World Long Rifle | <<locked>> | 80% | 50,270 psi | 79% | 2313 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 48,544 psi | 76% | 2313 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 49,095 psi | 77% | 2274 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 40,147 psi | 63% | 2234 fps | 98.7% |
| Somchem S361 | <<locked>> | 80% | 42,873 psi | 67% | 2224 fps | 97.5% |
| Somchem S365 | <<locked>> | 80% | 45,324 psi | 71% | 2290 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 40,886 psi | 64% | 2218 fps | 99.3% |
| Vihtavuori N150 | <<locked>> | 80% | 53,272 psi | 83% | 2300 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 49,530 psi | 78% | 2320 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 35,578 psi | 56% | 2116 fps | 98% |
| Vihtavuori N170 | <<locked>> | 96% | 50,937 psi | 80% | 2398 fps | 95.5% |
| Vihtavuori N550 | <<locked>> | 80% | 48,660 psi | 76% | 2323 fps | 100% |
| Vihtavuori N555 | <<locked>> | 80% | 39,958 psi | 63% | 2228 fps | 100% |
| Vihtavuori N560 | <<locked>> | 80% | 38,667 psi | 61% | 2257 fps | 96.7% |
| Vihtavuori N565 | <<locked>> | 82% | 34,026 psi | 53% | 2156 fps | 95.4% |
| Vihtavuori N568 | <<locked>> | 90% | 38,696 psi | 61% | 2297 fps | 95.7% |
| Vihtavuori N570 | <<locked>> | 96% | 45,136 psi | 71% | 2444 fps | 95.6% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 48,428 psi | 76% | 2283 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 50,807 psi | 80% | 2388 fps | 100% |
| Winchester StaBALL HD | 69.7 gr | 80% | 31,966 psi | 50% | 2205 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 37,376 psi | 59% | 2159 fps | 97.9% |
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 79 powders for .338 Norma Mag. loaded with the .338 | 300gr | MAKER Expanding Subsonic. Hodgdon Retumbo delivers the highest muzzle velocity at 2,595 fps; across all powders the maximum-charge window runs from 1,493 fps to 2,595 fps. ADI AR 2217 gives the best case fill at 100 %, and 79 of the 79 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 300.0 gr projectile in 0.338" calls for a 1:11.5 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, Winchester StaBALL HD rank at the top here: for .338 Norma Mag. with the .338 | 300gr | MAKER Expanding Subsonic they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, Alliant Reloder-50, Lovex D100, Shooters World 50 BMG 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.