When it comes to big game hunting and long-range shooting, there are several popular calibers to choose from. Two of the most common choices are the 300 Winchester Magnum (300 Win Mag) and the 338 Remington Ultra Magnum (338RUM). While both cartridges are powerful and effective, they have some significant differences that may influence which one is the better choice for your needs.
Here is the short answer:
The 300 Win Mag is a round that is more versatile, is more common, and has less recoil than the 338 RUM. However, the 338 RUM has far more energy at close ranging making it better suited for taking large and/or dangourus game at ranges within 500 yards.
Now that we have looked at the short answer, we can look in-depth at each cartridge, their ballistics, and how they compare in-depth.
In-depth Look at the 300 Win Mag
The 300 Winchester Magnum was introduced in 1963 and quickly gained popularity for its performance which separated it from most other cartridges of its time. It uses a belted magnum case and is capable of firing bullets ranging in weight from 150 to 220 grains. The 300 Win Mag has a reputation for accuracy and power, making it a popular choice for big game hunting, including elk, moose, and bear.
This round is often considered to be one of the lighter magnum cartridges that still offers a ballistic advantage over the smaller standard action cartridges. Oftentimes, the 300 Winchester magnum is regarded as the smallest cartridge that can comfortably take all game animals in America.
Here is a ballistics chart of the 300 Win Mag with a 180-grain soft point bullet:
| Range (YD) | drop (IN) | wind drift (IN) | velocity FPS | energy ft-lb |
| 0 | -1.5 | 0 | 2960 | 3502 |
| 50 | -0.2 | 0.1 | 2852 | 3250 |
| 100 | 0 | 0.7 | 2746 | 3013 |
| 150 | -0.9 | 1.6 | 2643 | 2791 |
| 200 | -3.1 | 2.9 | 2542 | 2582 |
| 250 | -6.6 | 4.5 | 2443 | 2385 |
| 300 | -11.6 | 6.6 | 2346 | 2200 |
| 350 | -18.2 | 9.2 | 2252 | 2027 |
| 400 | -26.5 | 12.3 | 2160 | 1864 |
| 450 | -36.6 | 15.9 | 2070 | 1712 |
| 500 | -48.8 | 20 | 1982 | 1570 |
In-depth Look at the 338 RUM
The 338 Remington Ultra Magnum (RUM) is widely recognized to be one of the most influential and effective long-range hunting cartridges existing in modern times. It’s expansive case diameter and lengthy neck are perfect for shooting high ballistic coefficient bullets at extreme ranges with superior accuracy.
The combination of heavy bullets and high velocities makes the RUM an ideal selection for many big game hunters who are searching to take down animals from distances within 500 yards without the risk of a mediocre shot leading to a long night of tracking. The RUM is capable of launching bullets that weigh up to 200 grains at velocities nearly reaching 3000 feet per second, rendering it suitable for even the largest species of game when fired at a distance far beyond what would be considered normal. Furthermore, its superior ballistics also make it a remarkable choice for target shooters who require utmost accuracy out past 1000 yards or more.
Here is a ballistic chart of the 338 RUM with a 210-grain Nolser Accubond:
| Range (YD) | drop (IN) | wind drift (IN) | velocity FPS | energy ft-lb |
| 0 | -1.5 | 0 | 3050 | 4337 |
| 50 | -0.2 | 0.1 | 2929 | 3999 |
| 100 | 0 | 0.7 | 2811 | 3683 |
| 150 | -0.9 | 1.7 | 2696 | 3388 |
| 200 | -2.9 | 3 | 2584 | 3113 |
| 250 | -6.3 | 4.8 | 2475 | 2855 |
| 300 | -11 | 7 | 2368 | 2614 |
| 350 | -17.4 | 9.8 | 2264 | 2390 |
| 400 | -25.4 | 13.1 | 2163 | 2181 |
| 450 | -35.3 | 16.9 | 2064 | 1986 |
| 500 | -47.2 | 21.3 | 1968 | 1805 |
In-depth Comparison
When comparing the 300 Win Mag and 338 RUM, there are several factors to consider.
The 300 Win Mag has less energy than the 338 RUM, which is a disadvantage against big game animals however, it lends it better to being used for a wider array of game animals. The 338RUM is ideal for larger game as it uses heavier bullets and has more energy than the 300 Win mag.
Balliticaly, these rounds are pretty tied. The only real separating factor when comparing the ballistics of the two rounds is the higher energy of the 338 RUM. However, for long-range target shooting energy does not play as bi of a role as drop and wind drift.
When it comes to cost and availability, the 300 Win Mag beats the 338 RUM. The 300 Win Mag has been around longer and is used by far more militaries and civilians around the world. Naturally, this means it si produced by more ammo companies and is going to be easier to find and cheaper to buy.
Versatility-wise, the 300 Win Mag also outcompetes the 338 RUM here. The 300 Winchester Magnum is produced in far more bullet weights and has more reloading data out there meaning you can really customize what you want to form your rifle without much effort. this will lend the 300 Win Mag to be a more well-rounded cartridge than the 338 RUM.
The last thing to consider is how easy these rounds are to shoot. The 300 Winchester Mangum has 8-10 less foot-pounds of recoil than the 338 and 1-pound less recoil velocity. This means the 338 RUM is going to be less than ideal for those who are shooting for long duration of time or those who are more sensitive to recoil.