7mm Rem Mag vs 300 Win Mag: Timeless Big Game Hunting Cartridges

Written by Sam Jacobs Subject: Gun Rights

In the world of magnum hunting cartridges, none are more ubiquitous than the 7mm Remington Magnum and 300 Winchester Magnum.

These two belted magnum cartridges have been at odds with each other since their release in the 1960's as they both offer extremely impressive downrange performance that surpassed the most popular hunting rounds of the day, like the 30-06 Springfield.

The 300 Win Mag offers hunters higher kinetic energy and heavier bullet options while the 7mm Rem Mag provides shooters with comparable stopping power (albeit it slightly lower) with considerably less recoil.

Many hunters hem and haw about which round makes the better choice for their new rifle, as this caliber debate has been raging for well over half a century.

In this article, we will evaluate the mighty 7mm vs 300 Win Mag to help you understand the differences between the two and give you a clearer understanding of which cartridge is best for your shooting and big game hunting needs.

What is the difference between the 7mm Rem Mag and the 300 Win Mag?

The main difference between the 7mm Rem Mag and 300 Winchester Magnum is bullet diameter each cartridge fires and their recoil. The 300 Win Mag fires a 0.308" caliber bullets which are generally heavier and have higher recoil while the 7mm Rem Mag fires a 0.284" diameter bullet that is lighter and has less recoil.

Cartridge Specs

When evaluating centerfire cartridges, it's a good idea to analyze the cartridge specs to gain more knowledge of each.

The 300 Winchester Magnum (300 WM) and 7mm Remington Magnum (7mm RM) are two rifle cartridges that have been at odds with each other since their release. It also didn't help that they were released one year apart, as this only fueled their rivalry.

Both rounds are part of the belted magnum family of cartridges that descended from the legendary 375 H&H Magnum. The 7mm Rem Mag made it to market first in 1962 and was released alongside the company's new bolt-action rifle, the Remington Model 700. The 7mm Magnum was touted as being a superior option to the 30-06 Springfield in every ballistic category for all bullet weights.

In contrast, the 300 Win Mag was released one year later in 1963 and was a late addition to Winchester's belted magnum cartridge line that included the 264 Winchester Magnum, 338 Win Mag, and 458 Win Mag.

Although the 7mm Rem Mag and 300 Win Mag have the same parent case in the 375 H&H Magnum, this is where the similarities end for these two cartridges.

The first and one of the most significant differences is the bullet diameter each round fires. The 7mm Rem Mag fires a 0.284" diameter bullet while the 300 Win Mag fires a 0.308" bullet diameter.

The 300 Win Mag is typically loaded with bullet weights between 150-230 grains with the 150 gr, 165 gr, 180 gr, 200 gr, and 220 gr bullets being the most popular in factory ammo.

In contrast, the 7mm RM can fire bullets between 139 and 175 grains with the 140 gr, 150 gr, 160 gr, and 175 gr factory loads being the most popular.

When comparing these two magnum cartridges side-by-side, it's clear that the 300 Win Mag is slightly taller than the 7mm RM. The 300 WM has a case length of 2.62" and overall length of 3.34" compared to 2.5" and 3.29" for the 7mm RM, respectively.

This overall length allows both cartridges to fit into a standard-length action. This is preferable to a magnum action, as a standard or long action is lighter and has a shorter bolt throw for faster follow-up shots.

The longer case length as well as shoulders that sit 0.156" further forward gives the 300 Win Mag approximately a 14% advantage in case capacity. The case capacity of the 7mm Rem Mag is 82 grains while the 300 WM can hold 93.8 grains of propellant.

As the 300 Win Mag can be loaded slightly hotter, it also is rated to handle more chamber pressure than the 7mm RM. Per SAAMI specs, the 300 Win Mag can safely handle 64,000 psi while the 7mm Rem Mag is rated slightly lower at 61,000 psi.

With all that extra case capacity, heavier projectiles, and higher pressures, it should come as no surprise that the 300 Win Mag has higher recoil. How much is the big question.


Recoil is an important consideration when purchasing a new rifle as a round with heavy recoil will be more difficult to control and will slow your rate of follow up shots. The potential for flinching is also an issue for cartridges with heavy recoil.

Felt recoil will differ from shooter to shooter and is often dependent on firearm choice, stance, and your chosen factory ammo or handloads. However, free recoil is a more objective measure of how hard a cartridge hits based on firearm weight, muzzle velocity, powder charge, and bullet weight.

For the purpose of this recoil comparison, we selected two rounds that are excellent for long range shooting as well as harvesting a variety of game animals. The rounds selected were the Nosler 168 gr Accubond Long Range traveling at 2,880 fps for 7mm Rem Mag and the Hornady 200 gr ELD-X traveling at 2,850 fps for 300 WM.

The rifle for this comparison will be the Remington 700 SPS Stainless bolt-action rifle weighing 7.6 lbs. This rifle was chosen as it can fire both cartridges and provides a closer apples-to-apples recoil comparison.

Given this rifle and these two rounds, the 7mm Remington Magnum will have a free recoil measurement of 29 ft-lbs compared to 39 ft-lbs for the 300 Win Mag.

This is one of the main selling points that supporters of the 7mm Rem Mag often cling to, that the 7mm Magnum has about 25% less recoil than the 300 Win Mag.

Continue reading the full guide on 7mm Rem Mag vs 300 Win Mag here.