Ballistic Differences Between Bullets of the Same Weight

Suppose you had to choose a 150-grain, .30-06 cartridge for a hunting trip to Colorado where you could encounter 500-yard shots at game.  Does it matter which bullet type you select from a ballistics perspective?  The short answer is yes.  The table below shows the differences in ballistic performance between two popular Winchester .30-06 cartridges. Cartridge “A” is the venerable 150-grain Power Point.  Side note, it’s also the cheapest Winchester .30-06 ammo you can buy which adds to its popularity.  Cartridge “B” is Winchester’s 150-grain Ballistic Silvertip.

Screen shot 2014-04-04 at 1.44.26 PMMuzzle velocity for both cartridges out of a 26″ barrel.  This table was created using a 200-yard zero and 10 mph crosswind with the ballistic calculator at Gundata.org.  Note how the Ballistic Silvertip maintains its velocity much better than the Power Point resulting in significantly less drop and wind drift beyond 300 yards.

What is the primary difference between these two cartridges outside of price?  The ballistic coefficient, or BC for short.  The BC for the Power Point is 0.294 while the BC for the Ballistic Silvertip is 0.435.  You can find these values online using the Winchester Ballistics Calculator.  This short video does a great job of explaining what factors into BC.

Speaking of price, ballistic-style cartridges are 50-100% more expensive than standard lead-tipped and FMJ bullets.  Expect to pay $35-45 for a box of 20.  If you will be shooting at longer ranges or windy conditions, the extra cost may be worth it.

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Winchester’s 150-grain Power Point in .30-06 (above) compared to the Ballistic Silvertip (below).  Differences in bullet geometry contribute to the Silvertip’s higher BC.

I went to Winchester’s online ballistic calculator to compare five, 150-grain, .30-06 cartridges: Power Point (BC=0.294), Ballistic Silvertip (BC=0.435), E-tip (BC=0.469), XP3 (BC=0.437), and Silvertip (BC=0.314).  The image below compares these cartridges head-to-head in a 10 mph crosswind at a range of 500 yards with a 200-yard zero.  As you can see, the best performance comes from the E-tip which has the highest BC.  Likewise, the worst performance is from the Power Point which has the lowest BC.

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Click image to enlarge.

Make sure your bullet is designed appropriately for the type of game you’ll be hunting. Some high performance bullets fragment versus expanding while retaining mass. Primary uses for the bullet should be listed on the box.  Sometimes the BC is also listed on the box.

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Winchester’s best bullet ballistically: the E-tip.

When you sight-in your rifle, make sure you zero with the same cartridge you’ll be hunting with.  As you’ve learned, bullet drop and windage varies widely based on BC, and you can’t assume bullets of the same weight will fly equally.  Don’t compromise your hunt by zeroing with less expensive ammunition at the range.  If you shoot your bolt-action deer rifle very little through the year, I suggest using only one type of ammunition. The consistency you will see at the range and on the hunt is worth the extra expense.

You can probably tell that I’m a fan of Winchester ammo.  If I must choose between it and something else, I almost always choose Winchester for a few reasons.  Winchester supplies free resources like its online ballistic calculator, its ammo is reasonably priced, and variety is offered in each caliber.  However, if you prefer other brands, I suggest you use this ballistic calculator which has many BCs pre-loaded.  Be sure to click “Advance options…” to enter zero range, wind speed, scope height, etc.