.300 Winchester Magnum for Long Distance Shooting

The recent post comparing the .338 Lapua Magnum (.338 LM) to the 6.5mm Creedmoor (6.5 CM) generated some discussion and some questions. One question, which came in via Twitter, asked somebody asking how the .300 Winchester Magnum (.300 WinMag) fits in?

I’ll attempt to answer that. But, please keep in mind that I have no experience with the .300 WinMag what so ever.

I’m going to reuse the data from the .338 LM vs 6.5 CM post and add the .300 WinMag to it. First up is the advertised ballistic information from the Hornady Match product line up.

Advertised Ballistics6.5mm Creedmoor.300 Winchester Magnum.338 Lapua Magnum
Bullet140 grain ELD Match178 grain ELD Match285 grain ELD Match
Secional density.287.268.356
Ballistic coefficient.646 (G1)
.326 (G7)
.547 (G1)
.275 (G7)
.789 (G1)
.394 (G7)
Muzzle velocity2710 fps2960 fps2745 fps
Muzzle energy2283 ft/lb3462 ft/lb4768 ft/lb
Advertised ballistics from Hornady

I wasn’t surprised to see that the ballistic coefficient (BC) of .300 WinMag was lower than both the 6.5 CM and the .338 LM. This is typical of fatter .308 caliber projectiles used in the .300 WinMag cartridge tend to be about the same overall length as the skinnier .264 caliber projectiles used in the 6.5 CM. This lower BC implies the projectile from the .300 WinMag will experience drop and wind drift a faster than the .338 LM and the 6.5 CM.

However, the initial muzzle velocity of the .300 WinMag is significantly higher than the other two. This begs the question, will the lower BC really matter in terms of comparing the effective range of the .300 WinMag against the other two cartridges? It’s time to use a ballistic calculator and figure out the velocity, drop and drift at various distances.

The following table compares the velocity of the projectiles at various distances:

Velocity6.5mm Creedmoor.300 Winchester Magnum.338 Lapua Magnum
500 yards2059 fps2159 fps2198 fps
1000 yards1516 fps1508 fps1765 fps
1500 yards1135 fps1086 fps1332 fps
1750 yards1026 fps980 fps1185 fps
Velocity at extended distances

Velocity is important to keep in mind when shooting at extended distances with supersonic projectiles. Once the velocity has decreased enough to begin crossing the transonic barrier (meaning when the projectile starts transitioning from being supersonic to subsonic) most projectiles will begin to destabilize and eventually tumble which results in a significant loss of accuracy. Which for precision shooting, this is what will determine the cartridges effective range. This roughly happens when a cartridge slows down under 1200 feet per second (fps).

To be honest, I was quite a bit surprised by these numbers. I was expecting the .300 WinMag to have an effective range somewhere between the 6.5 CM and the .338 LM due to it being a magnum cartridge. However, it looks like the lower BC really made a difference. The data shows that by the 1000 yard mark the .300 WinMag projectile is traveling at a lower velocity than both the projectiles from the 6.5 CM and the .338 LM. The projectile from the .300 WinMag begins going transonic at around 1350 yards where as the projectiles from the 6.5 CM and the .338 LM begin going transonic at around the 1400 yard mark and the 1750 yard mark respectively.

So in terms of effective range for long distance shooting, the .300 WinMag is edged out by the 6.5 CM.

Okay. That’s cool. But how much drop will these projectiles experience at the same extended distances?

Drop6.5mm Creedmoor.300 Winchester Magnum.338 Lapua Magnum
500 yards53.1″45.2″49.2″
1000 yards316.8″284.1″280.7″
1500 yards970.6″921″813″
1750 yards1531.3″1492.5″1249.6″
Drop at extended distances

The drop data confirms that .300 WinMag has a flatter trajectory than the 6.5 CM, but not quite as flat as the .338 LM at extended distances beyond 500 yards. Up to just beyond the 500 yard mark, the .300 WinMag has the flattest trajectory of the group. This seems like an expected result as the .300 WinMag has the fastest projectile of the bunch from the muzzle and it also has the projectile that slows down the fastest due to its lower BC.

One might be surprised that even at extended distances the .300 WinMag is flatter than the 6.5 CM all the way out to the 1750 yard mark (basically the mile mark). This is also a result of the .300 WinMag’s greater muzzle velocity which results in a shorter flight time out to the 1750 yard mark. However, the difference in drop between the two at that distance is not really relevant since that distance is outside their effective range.

Let’s look at wind drift.

Drift6.5mm Creedmoor.300 Winchester Magnum.338 Lapua Magnum
500 yards14″15.3″11″
1000 yards67″72.8″51″
1500 yards173″193.3″130″
1750 yards247″277.3″187″
Drift with a 10 mph cross wind at extended distances

The wind drift data shows that the projectile from the .300 WinMag is the most susceptible to wind drift out of the bunch. This is a result of the .300 WinMag having the lowest BC out of the bunch. Furthermore, this implies the .300 WinMag will be the least forgiving of the three to errors in wind calls.

After writing all of this, it might seem that I am saying that the .300 WinMag isn’t a better choice for long distance shooting against the 6.5 CM or the .338 LM. After all, it has the shortest effective range, a middle of the road trajectory, and is most susceptible to wind drift. But that’s not quite what I think.

I think it’s fair to say that on a windy day, the .300 WinMag will be the most difficult cartridge of the three to get accurate hits with due to is susceptibility to wind drift. On a day with mild or no winds the .300 WinMag can basically do what the 6.5 CM can do, perhaps even a little better due to the .300 WinMag’s flatter trajectory. On the other hand, the .300 WinMag will provide the shooter with more recoil to deal with.

I also think it’s fair to say that neither the 6.5 CM nor the .300 WinMag would be a better choice over the .338 LM for mile long shots.

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