Load Specifications
Bullet Manufacturer:TWENTY-NINE
Bullet Weight:191 gr
Bullet Diameter:0.338"
Bullet Length:<<locked>>
Caliber:.338 Rem. Ultra Mag. load data
Case Length (l3):2.76"
Cartridge Length (C.O.L.):<<locked>>
Case Capacity:110 Grains of Water
Primer Size:Large Rifle Magnum (LRM)
Barrel Length:24"
Max. allowed Pressure:63,817 psi
Recommended Twist Rate:1:12.5
Load data in caliber .338 Rem. Ultra Mag. with .338 | 191gr | TWENTY-NINE ERTP bullet and 105 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Alliant Reloder-16, ReloadSwiss RS 70 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: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2495 | <<locked>> | 84% | 56,840 psi | 89% | 2835 fps | 100% |
| Accurate 2700 | <<locked>> | 84% | 54,810 psi | 86% | 2844 fps | 98.2% |
| Accurate 3100ᴾ | <<locked>> | 100% | 52,373 psi | 82% | 2874 fps | 99.2% |
| Accurate 4064 | <<locked>> | 86% | 57,334 psi | 90% | 2890 fps | 100% |
| Accurate 4350 | <<locked>> | 92% | 54,375 psi | 85% | 2933 fps | 99.9% |
| Accurate High Countryᴾ | <<locked>> | 100% | 57,508 psi | 90% | 3074 fps | 97.4% |
| ADI AR 2206H | <<locked>> | 82% | 56,231 psi | 88% | 2920 fps | 100% |
| ADI AR 2208 | <<locked>> | 88% | 57,406 psi | 90% | 2920 fps | 100% |
| ADI AR 2209 | <<locked>> | 98% | 55,666 psi | 87% | 2972 fps | 97.8% |
| ADI AR 2213ᴾ | <<locked>> | 100% | 53,403 psi | 84% | 2956 fps | 96% |
| Alliant Power Pro 2000-MR | <<locked>> | 84% | 56,869 psi | 89% | 3045 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 98% | 55,753 psi | 87% | 2969 fps | 97.8% |
| Alliant Power Pro Varmint | <<locked>> | 98% | 55,753 psi | 87% | 2969 fps | 97.8% |
| Alliant Reloder- TS 15.5 | <<locked>> | 86% | 54,737 psi | 86% | 2894 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 84% | 54,795 psi | 86% | 2913 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 94% | 55,056 psi | 86% | 2992 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 90% | 56,710 psi | 89% | 3018 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 98% | 54,955 psi | 86% | 2959 fps | 97.7% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 52,127 psi | 82% | 2956 fps | 97.4% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 49,095 psi | 77% | 2897 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 42,830 psi | 67% | 2812 fps | 98.4% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 56,927 psi | 89% | 3091 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 82% | 56,318 psi | 88% | 2930 fps | 100% |
| Bofors RP15ᴾ | <<locked>> | 100% | 47,790 psi | 75% | 2877 fps | 96.2% |
| Bofors RP3 | <<locked>> | 86% | 55,666 psi | 87% | 2910 fps | 100% |
| Bofors RP5ᴾ | <<locked>> | 100% | 52,127 psi | 82% | 2956 fps | 97.4% |
| Bofors RP7 | <<locked>> | 90% | 55,071 psi | 86% | 2887 fps | 98.4% |
| Hodgdon H380 | <<locked>> | 86% | 56,043 psi | 88% | 2923 fps | 99.9% |
| Hodgdon H414 | <<locked>> | 92% | 56,840 psi | 89% | 2986 fps | 99.2% |
| Hodgdon H4350 | <<locked>> | 90% | 56,449 psi | 88% | 2943 fps | 98.1% |
| Hodgdon H4831ᴾ | <<locked>> | 100% | 57,406 psi | 90% | 2966 fps | 96.2% |
| Hodgdon H4831 SCᴾ | <<locked>> | 100% | 56,086 psi | 88% | 2943 fps | 95.9% |
| Hodgdon H4895 | <<locked>> | 82% | 56,869 psi | 89% | 2927 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 96% | 55,463 psi | 87% | 2913 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 84% | 57,319 psi | 90% | 2963 fps | 100% |
| Hodgdon Superformance | <<locked>> | 92% | 57,406 psi | 90% | 3022 fps | 99.1% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,230 psi | 57% | 1844 fps | 100% |
| Hodgdon VARGET | <<locked>> | 82% | 54,273 psi | 85% | 2877 fps | 100% |
| IMR 3031 | <<locked>> | 82% | 57,348 psi | 90% | 2904 fps | 100% |
| IMR 4064 | <<locked>> | 86% | 56,898 psi | 89% | 2907 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 84% | 56,173 psi | 88% | 2887 fps | 98.9% |
| IMR 4350 | <<locked>> | 94% | 56,057 psi | 88% | 2917 fps | 98.6% |
| IMR 4451 Enduron | <<locked>> | 90% | 56,681 psi | 89% | 2917 fps | 99% |
| IMR 4831 | <<locked>> | 94% | 54,984 psi | 86% | 2927 fps | 100% |
| IMR 4895 | <<locked>> | 84% | 56,260 psi | 88% | 2943 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 98% | 55,201 psi | 87% | 2900 fps | 95.9% |
| Lovex D073.6 | <<locked>> | 82% | 56,753 psi | 89% | 2890 fps | 100% |
| Lovex S060 | <<locked>> | 82% | 54,998 psi | 86% | 2841 fps | 100% |
| Lovex S062 | <<locked>> | 86% | 57,130 psi | 90% | 2897 fps | 100% |
| Lovex S065 | <<locked>> | 92% | 56,811 psi | 89% | 2913 fps | 99.7% |
| Lovex S070 | <<locked>> | 92% | 54,694 psi | 86% | 2900 fps | 99% |
| Lovex S071ᴾ | <<locked>> | 100% | 43,395 psi | 68% | 2726 fps | 97.7% |
| Norma 201 | <<locked>> | 82% | 54,897 psi | 86% | 2861 fps | 100% |
| Norma 202 | <<locked>> | 82% | 55,593 psi | 87% | 2858 fps | 100% |
| Norma 203B | <<locked>> | 86% | 57,740 psi | 90% | 2953 fps | 100% |
| Norma 204 | <<locked>> | 94% | 56,884 psi | 89% | 2969 fps | 97.8% |
| Norma MRPᴾ | <<locked>> | 100% | 55,535 psi | 87% | 3041 fps | 99.1% |
| Norma URP | <<locked>> | 94% | 56,811 psi | 89% | 2976 fps | 100% |
| Ramshot Big Game | <<locked>> | 84% | 54,998 psi | 86% | 2923 fps | 100% |
| Ramshot Hunter | <<locked>> | 94% | 55,680 psi | 87% | 2969 fps | 99.5% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 45,513 psi | 71% | 2812 fps | 96.5% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,709 psi | 58% | 1886 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 86% | 56,014 psi | 88% | 2907 fps | 99.3% |
| ReloadSwiss RS 52 | <<locked>> | 82% | 55,709 psi | 87% | 2979 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 88% | 56,028 psi | 88% | 3012 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 92% | 54,288 psi | 85% | 2956 fps | 99.9% |
| ReloadSwiss RS 70 | <<locked>> | 94% | 56,811 psi | 89% | 3038 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 42,032 psi | 66% | 2818 fps | 96.3% |
| Rottweil R 902 | <<locked>> | 84% | 55,608 psi | 87% | 2861 fps | 100% |
| Rottweil R 903 | <<locked>> | 88% | 55,506 psi | 87% | 2904 fps | 100% |
| Rottweil R 904 | <<locked>> | 98% | 57,334 psi | 90% | 2943 fps | 97% |
| Rottweil R 905 | <<locked>> | 98% | 54,056 psi | 85% | 2943 fps | 97.7% |
| Rottweil R 907 | <<locked>> | 90% | 55,071 psi | 86% | 2887 fps | 98.4% |
| Shooters World Long Rifle | <<locked>> | 92% | 56,811 psi | 89% | 2913 fps | 99.7% |
| Shooters World Match Rifle | <<locked>> | 82% | 56,753 psi | 89% | 2890 fps | 100% |
| Shooters World Precision | <<locked>> | 86% | 57,130 psi | 90% | 2897 fps | 100% |
| Shooters World SW4350 | <<locked>> | 92% | 54,694 psi | 86% | 2900 fps | 99% |
| SNPE Vectan SP 11 | <<locked>> | 88% | 57,261 psi | 90% | 2959 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 82% | 57,725 psi | 90% | 2920 fps | 99.9% |
| SNPE Vectan SP 9 | <<locked>> | 82% | 54,592 psi | 86% | 2884 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 82% | 55,666 psi | 87% | 2795 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 88% | 56,768 psi | 89% | 2792 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 92% | 56,637 psi | 89% | 2861 fps | 99% |
| SNPE Vectan Tubal 8000ᴾ | <<locked>> | 100% | 57,421 psi | 90% | 2999 fps | 98.2% |
| Somchem S335 | <<locked>> | 82% | 55,448 psi | 87% | 2792 fps | 100% |
| Somchem S341 | <<locked>> | 82% | 57,276 psi | 90% | 2904 fps | 100% |
| Somchem S355 | <<locked>> | 88% | 55,535 psi | 87% | 2900 fps | 100% |
| Somchem S361 | <<locked>> | 96% | 55,709 psi | 87% | 2874 fps | 95.8% |
| Somchem S365 | <<locked>> | 96% | 55,970 psi | 88% | 2972 fps | 100% |
| Somchem S385 | <<locked>> | 98% | 54,810 psi | 86% | 2920 fps | 98.5% |
| Vihtavuori N133 | <<locked>> | 82% | 56,115 psi | 88% | 2776 fps | 100% |
| Vihtavuori N135 | <<locked>> | 84% | 55,782 psi | 87% | 2822 fps | 100% |
| Vihtavuori N140 | <<locked>> | 84% | 56,130 psi | 88% | 2835 fps | 100% |
| Vihtavuori N150 | <<locked>> | 90% | 57,000 psi | 89% | 2874 fps | 100% |
| Vihtavuori N160 | <<locked>> | 92% | 55,288 psi | 87% | 2913 fps | 99.9% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 50,502 psi | 79% | 2835 fps | 97.4% |
| Vihtavuori N540 | <<locked>> | 84% | 54,549 psi | 85% | 2831 fps | 100% |
| Vihtavuori N550 | <<locked>> | 92% | 54,534 psi | 85% | 2920 fps | 99.9% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 54,998 psi | 86% | 2972 fps | 100% |
| Vihtavuori N560ᴾ | <<locked>> | 100% | 55,898 psi | 88% | 3031 fps | 96.3% |
| Winchester 6.5 StaBALL | <<locked>> | 92% | 55,187 psi | 86% | 2881 fps | 100% |
| Winchester 760 | <<locked>> | 92% | 57,029 psi | 89% | 2992 fps | 99.2% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 44,440 psi | 70% | 2946 fps | 100% |
| Winchester StaBALL Match | <<locked>> | 82% | 54,795 psi | 86% | 2894 fps | 100% |
| Winchester Supreme 780ᴾ | <<locked>> | 100% | 55,216 psi | 87% | 2913 fps | 97.7% |
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 2495 | <<locked>> | 80% | 50,024 psi | 78% | 2743 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 47,950 psi | 75% | 2733 fps | 96.9% |
| Accurate 3100 | <<locked>> | 90% | 37,072 psi | 58% | 2598 fps | 95.8% |
| Accurate 4064 | <<locked>> | 80% | 47,326 psi | 74% | 2746 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 35,752 psi | 56% | 2592 fps | 97.1% |
| Accurate High Country | <<locked>> | 96% | 49,806 psi | 78% | 2949 fps | 95.7% |
| ADI AR 2206H | <<locked>> | 80% | 52,721 psi | 83% | 2864 fps | 100% |
| ADI AR 2208 | <<locked>> | 80% | 44,715 psi | 70% | 2717 fps | 99.4% |
| ADI AR 2209 | <<locked>> | 92% | 45,658 psi | 72% | 2799 fps | 95.4% |
| ADI AR 2213 | <<locked>> | 98% | 49,893 psi | 78% | 2897 fps | 95% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 49,211 psi | 77% | 2923 fps | 99.9% |
| Alliant Power Pro Varmint | <<locked>> | 92% | 45,643 psi | 72% | 2795 fps | 95.5% |
| Alliant Power Pro Varmint | <<locked>> | 92% | 45,643 psi | 72% | 2795 fps | 95.5% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 45,049 psi | 71% | 2740 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 48,240 psi | 76% | 2808 fps | 99.8% |
| Alliant Reloder-16 | 69.1 gr | 80% | 35,099 psi | 55% | 2605 fps | 97.1% |
| Alliant Reloder-17 | <<locked>> | 80% | 39,726 psi | 62% | 2733 fps | 99.6% |
| Alliant Reloder-19 | <<locked>> | 92% | 45,092 psi | 71% | 2789 fps | 95.4% |
| Alliant Reloder-22 | <<locked>> | 96% | 45,469 psi | 71% | 2838 fps | 95.7% |
| Alliant Reloder-23 | <<locked>> | 82% | 27,354 psi | 43% | 2405 fps | 95.3% |
| Alliant Reloder-25 | <<locked>> | 94% | 35,404 psi | 55% | 2635 fps | 95.7% |
| Alliant Reloder-26 | 81.9 gr | 86% | 33,750 psi | 53% | 2638 fps | 96% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 52,591 psi | 82% | 2874 fps | 99.9% |
| Bofors RP15 | <<locked>> | 98% | 44,657 psi | 70% | 2818 fps | 95.3% |
| Bofors RP3 | <<locked>> | 80% | 45,455 psi | 71% | 2753 fps | 100% |
| Bofors RP5 | <<locked>> | 96% | 45,469 psi | 71% | 2838 fps | 95.7% |
| Bofors RP7 | <<locked>> | 82% | 42,656 psi | 67% | 2671 fps | 95.7% |
| Hodgdon H380 | <<locked>> | 80% | 45,774 psi | 72% | 2756 fps | 98.9% |
| Hodgdon H414 | <<locked>> | 82% | 40,553 psi | 64% | 2700 fps | 95.8% |
| Hodgdon H4350 | <<locked>> | 82% | 43,613 psi | 68% | 2720 fps | 95.2% |
| Hodgdon H4831 | <<locked>> | 98% | 53,577 psi | 84% | 2907 fps | 95.3% |
| Hodgdon H4831 SC | <<locked>> | 98% | 52,359 psi | 82% | 2884 fps | 95% |
| Hodgdon H4895 | <<locked>> | 80% | 53,272 psi | 83% | 2874 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 32,547 psi | 51% | 2500 fps | 97.8% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 50,024 psi | 78% | 2854 fps | 100% |
| Hodgdon Superformance | <<locked>> | 82% | 39,740 psi | 62% | 2703 fps | 95.1% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,992 psi | 42% | 1654 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 51,010 psi | 80% | 2825 fps | 100% |
| IMR 3031 | <<locked>> | 80% | 53,751 psi | 84% | 2858 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 47,007 psi | 74% | 2749 fps | 99.7% |
| IMR 4166 Enduron | <<locked>> | 80% | 49,400 psi | 77% | 2776 fps | 97.9% |
| IMR 4350 | <<locked>> | 84% | 40,640 psi | 64% | 2644 fps | 95.1% |
| IMR 4451 Enduron | <<locked>> | 80% | 41,539 psi | 65% | 2648 fps | 95.9% |
| IMR 4831 | <<locked>> | 80% | 34,418 psi | 54% | 2546 fps | 96.7% |
| IMR 4895 | <<locked>> | 80% | 49,472 psi | 78% | 2838 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 96% | 51,750 psi | 81% | 2844 fps | 95.1% |
| Lovex D073.6 | <<locked>> | 80% | 53,069 psi | 83% | 2838 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 51,764 psi | 81% | 2795 fps | 100% |
| Lovex S062 | <<locked>> | 80% | 47,282 psi | 74% | 2749 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 39,059 psi | 61% | 2598 fps | 96.7% |
| Lovex S070 | <<locked>> | 82% | 39,755 psi | 62% | 2628 fps | 95.7% |
| Lovex S071 | <<locked>> | 94% | 35,665 psi | 56% | 2566 fps | 95.3% |
| Norma 201 | <<locked>> | 80% | 51,605 psi | 81% | 2812 fps | 100% |
| Norma 202 | <<locked>> | 80% | 52,054 psi | 82% | 2812 fps | 100% |
| Norma 203B | <<locked>> | 80% | 47,587 psi | 75% | 2795 fps | 99.9% |
| Norma 204 | <<locked>> | 88% | 46,253 psi | 72% | 2792 fps | 95.5% |
| Norma MRP | <<locked>> | 90% | 38,972 psi | 61% | 2733 fps | 95.1% |
| Norma URP | <<locked>> | 80% | 35,650 psi | 56% | 2589 fps | 96.9% |
| Ramshot Big Game | <<locked>> | 80% | 47,863 psi | 75% | 2812 fps | 99.9% |
| Ramshot Hunter | <<locked>> | 82% | 37,028 psi | 58% | 2628 fps | 95.6% |
| Ramshot Magnum | <<locked>> | 98% | 42,380 psi | 66% | 2746 fps | 95.4% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,514 psi | 43% | 1693 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 45,992 psi | 72% | 2740 fps | 97.8% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 52,025 psi | 82% | 2923 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 42,235 psi | 66% | 2792 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 35,563 psi | 56% | 2608 fps | 96.7% |
| ReloadSwiss RS 70 | 75.5 gr | 80% | 34,751 psi | 54% | 2608 fps | 95.8% |
| ReloadSwiss RS 76 | <<locked>> | 98% | 39,189 psi | 61% | 2753 fps | 95% |
| Rottweil R 902 | <<locked>> | 80% | 49,124 psi | 77% | 2766 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 42,656 psi | 67% | 2694 fps | 99.8% |
| Rottweil R 904 | <<locked>> | 94% | 50,372 psi | 79% | 2828 fps | 95.4% |
| Rottweil R 905 | <<locked>> | 92% | 44,121 psi | 69% | 2772 fps | 95.3% |
| Rottweil R 907 | <<locked>> | 82% | 42,656 psi | 67% | 2671 fps | 95.7% |
| Shooters World Long Rifle | <<locked>> | 80% | 39,059 psi | 61% | 2598 fps | 96.7% |
| Shooters World Match Rifle | <<locked>> | 80% | 53,069 psi | 83% | 2838 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 47,282 psi | 74% | 2749 fps | 100% |
| Shooters World SW4350 | <<locked>> | 82% | 39,755 psi | 62% | 2628 fps | 95.7% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 43,787 psi | 69% | 2746 fps | 99.6% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 53,867 psi | 84% | 2864 fps | 99.7% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 51,213 psi | 80% | 2835 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 52,402 psi | 82% | 2749 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 44,222 psi | 69% | 2618 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 38,261 psi | 60% | 2539 fps | 95.1% |
| SNPE Vectan Tubal 8000 | <<locked>> | 92% | 43,700 psi | 68% | 2766 fps | 95.1% |
| Somchem S335 | <<locked>> | 80% | 52,199 psi | 82% | 2746 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 53,490 psi | 84% | 2851 fps | 100% |
| Somchem S355 | <<locked>> | 80% | 43,149 psi | 68% | 2697 fps | 99.7% |
| Somchem S361 | <<locked>> | 94% | 52,069 psi | 82% | 2818 fps | 95% |
| Somchem S365 | <<locked>> | 80% | 32,140 psi | 50% | 2546 fps | 98.9% |
| Somchem S385 | <<locked>> | 90% | 41,974 psi | 66% | 2697 fps | 95.6% |
| Vihtavuori N133 | <<locked>> | 80% | 52,924 psi | 83% | 2736 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 49,211 psi | 77% | 2733 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 49,429 psi | 77% | 2743 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 41,089 psi | 64% | 2628 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 37,072 psi | 58% | 2592 fps | 97.3% |
| Vihtavuori N165 | <<locked>> | 96% | 44,208 psi | 69% | 2726 fps | 95.9% |
| Vihtavuori N540 | <<locked>> | 80% | 47,790 psi | 75% | 2733 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 36,564 psi | 57% | 2592 fps | 97% |
| Vihtavuori N555 | <<locked>> | 82% | 30,037 psi | 47% | 2484 fps | 95.5% |
| Vihtavuori N560 | <<locked>> | 98% | 52,025 psi | 82% | 2966 fps | 95.4% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 36,477 psi | 57% | 2562 fps | 99.1% |
| Winchester 760 | <<locked>> | 82% | 40,712 psi | 64% | 2703 fps | 95.9% |
| Winchester StaBALL HD | <<locked>> | 86% | 27,630 psi | 43% | 2493 fps | 96.4% |
| Winchester StaBALL Match | <<locked>> | 80% | 51,329 psi | 80% | 2841 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 94% | 44,541 psi | 70% | 2740 fps | 95.2% |
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 .338 Rem. Ultra Mag. loaded with the .338 | 191gr | TWENTY-NINE ERTP. Alliant Reloder-26 delivers the highest muzzle velocity at 3,091 fps; across all powders the maximum-charge window runs from 1,844 fps to 3,091 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 (440 MPa), the top charges use 57–90 %, leaving at least 10 % headroom. The 191.0 gr projectile in 0.338" calls for a 1:12.5 twist; slower twists will usually not stabilise this weight. Accurate 3100, Accurate High Country, ADI AR 2213 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-16, ReloadSwiss RS 70, Alliant Reloder-26 rank at the top here: for .338 Rem. Ultra Mag. with the .338 | 191gr | TWENTY-NINE ERTP 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.