Saturday, December 29, 2018

Comparing the 5.56X45mm NATO with the .243 Winchester at long distances

Velocity in feet per second. Range in yards. All calculations done with Hornaday's Ballistic Calculator
62 grain 855 projectile in the 5.56mm and 105 match hollowpoint in the 243 Win with a G1 of .53

Initial velocities of 3000fps for the 5.56mm and 2800fps for the .243 Win.

The .243 Win has as much energy at 800 yards as the 5.56mm has at 200 yards.
But can you hit with it?

At 800 yards, a 13 yard miscalculation in range results in a 12" drop error for the 5.56mm. That is enough drop to take a bullet out of a 24" tall target zone. For the .243 Winchester, a 21 yard miscalculation in range will result in 12" of error.
If the first rule of gun fighting is to hit the target, then the .243 Win is 58% better than the 5.56mm. It also has less wind drift.

  • Shorter barrel life.
  • 35% less ammo per pound carried
  • More recoil


  1. I think go with the .243 or similar. In the middle of combat...unless sniping and who uses 5.56 for the middle of combat who has the time to really worry much about windage and elevation ?? A lot handier if your round goes more or less where you point. As a lot of combat is likely 50-300 meters elevation may not be a big problem. However, windage can still be a problem. Also, as I recall, the troops complained that leaves ( trees etc) in a jungle environment ( like Nam) could deflect a 5.56 round where a heavier round was bothered less.

  2. Regarding heavy vs. light bullets and deflections, I think I need to see documentation regarding this. Not saying it's not true to a certain extent, but it kinda depends on where the deflection occurs relative to the target.
    Example. The last two years a buddy (years a competitive shooter, Master class) has wounded two deer, one using .44 mag. rifle and the other with a new .450 Bushmaster. Both were short shots (25-40 yds.) that should've dropped the bucks in their tracks but failed to do so. Further inspection showed that very small branches had apparently deflected the shots enough to only wound the deer. These .45 caliber rifles should be the very definition of "brush guns".
    For sniping distances, a lot of long distance shooters really like the 6.5 caliber stuff and the .308 has a long history of good results.

  3. ...and yes, the .243 is a great caliber. My Yooper brother has killed dozens of whitetails with one.

    1. Were they all lined up when he pulled the trigger?

      Just kidding.


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