Two rounds that have near the same bullet size and are used for the same tasks are the 325 WSM and the 338 Win Mag. However, there are differences between these two rounds that are often not brought up. So in this article, we will compare the two round to see which is better and why.
Here is the short answer:
The 325 WSM offers a flatter trajectory and higher velocity. However, the 338 Win Mag has more energy, less wind drift, and better energy retention at long range.
Now that we have looked at the short answer, we can look closer at each cartridge, their ballistics, and how they compare in-depth.
In-Depth Look at the 325 WSM
The 325 WSM is a short magnum cartridge developed by Winchester in 2005. Based on the 404 Jeffery case, it is necked down to hold a .323-inch bullet. Due to the large bullet diameter and case size, this round is popular for elk, moose, bison, and bear hunting.
The cartridge offers a high velocity and flat trajectory, making it suitable for long-range shooting. The 325 WSM has a bullet weight ranging from 180 to 220 grains, and it delivers muzzle velocities of around 2950 to 3050 feet per second. It has a maximum effective range of around 800 yards, making it a good choice for open country hunting.
Here is a ballistics chart of the 325 WSM with a 200-grain Nosler Accubond:
| range (YD) | drop (IN) | wind drift (IN) | velocity FPS | energy ft-lb |
| 0 | -1.5 | 0 | 2950 | 3864 |
| 50 | -0.2 | 0.2 | 2844 | 3593 |
| 100 | 0 | 0.7 | 2741 | 3337 |
| 150 | -1 | 1.6 | 2641 | 3097 |
| 200 | -3.1 | 2.8 | 2542 | 2870 |
| 250 | -6.7 | 4.4 | 2446 | 2656 |
| 300 | -11.6 | 6.4 | 2352 | 2456 |
| 350 | -18.2 | 9 | 2259 | 2267 |
| 400 | -26.5 | 12 | 2169 | 2090 |
| 450 | -36.6 | 15.5 | 2081 | 1923 |
| 500 | -48.8 | 19.5 | 1995 | 1768 |
In-Depth Look at the 338 Winchester
The 338 Winchester is a classic cartridge that has been around since 1958. Based on the 375 H&H case, it is necked down to hold a .338 inch bullet. The cartridge offers a larger bullet and more energy, making it a good choice for hunting big game and is even a popular choice among big game hunting guides in Alaska.
The 338 Winchester has a bullet weight ranging from 180 to 250 grains, and it delivers muzzle velocities of around 2600 to 2800 feet per second. It has a maximum effective range of around 600 yards, making it a good choice for hunting in mountainous terrain.
Here is a ballistics chart of the 338 Winchester Magnum with a 225-grain soft point bullet:
| range (YD) | drop (IN) | wind drift (IN) | velocity FPS | energy ft-lb |
| 0 | -1.5 | 0 | 2850 | 4058 |
| 50 | -0.2 | 0.2 | 2754 | 3790 |
| 100 | 0 | 0.7 | 2661 | 3537 |
| 150 | -1.1 | 1.5 | 2569 | 3297 |
| 200 | -3.4 | 2.7 | 2479 | 3071 |
| 250 | -7.1 | 4.2 | 2391 | 2856 |
| 300 | -12.5 | 6.2 | 2305 | 2654 |
| 350 | -19.4 | 8.7 | 2221 | 2463 |
| 400 | -28.2 | 11.6 | 2138 | 2283 |
| 450 | -38.7 | 14.9 | 2057 | 2114 |
| 500 | -51.4 | 18.7 | 1978 | 1954 |
In-Depth Comparison
Ballistically, the 325 WSM has a better trajectory and higher velocity. But it does not have as much energy or retain its energy as well as the 338 Winchester magnum. Additionally, the 338 will have slightly better wind drift.
Recoil-wise, both these rounds are similar kick with the 325 WSM having slightly more recoil. Keep in mind this difference is highly dependent on what bullet size you are using and how much powder is in the case.
The last issue to cover is cost and availability. The 338 Winchester is generally cheaper than the 325 WSM because it is a more prominent round. Not to mention, there is more load data and more bullet weights available for the 338 Winchester making it an overall more versatile round.
Conclusion
In conclusion, the 325 WSM and the 338 Winchester are excellent cartridges for big game hunting, but they have different strengths and weaknesses. The 325 WSM offers a flatter trajectory and higher velocity, making it a better choice for long-range shooting, while the 338 Winchester has a larger bullet and more energy, making it a better choice for big game hunting.