Rifle bullets have traditionally been constructed with a flat, or untapered, base. Over the years bullet design has evolved in an attempt to make the projectiles more efficient. Rifle bullets are now designed with numerous variations in shape, size and construction to make it more proficient for its intended purpose. On such innovation is the boat tail design.
What is Boat Tail Ammo?
Boat tail bullets, commonly designated as BT, are constructed with a tapered base, like the stern of a boat. As the back of a boat is narrower than the middle to reduce friction as it moves through the water, the taper at the base of the bullet is designed to help reduce wind resistance, referred to as drag. This in turn helps to both flatten trajectory and improve long-range accuracy and power, which is defined as the bullet’s coefficiency.
The Pros and Cons of Boat Tail Ammo
There are some real differences between boat tail bullets and traditional flat bottom ammo performance. However, depending on how the bullet is used, the pros and cons may not be that much of an issue.
- Boat tail bullets outperform flat-tailed bullets at longer ranges of 200 yards or more.
- Greater Accuracy: Boat tail bullets experience less resistance and therefore produce a flatter trajectory and greater accuracy at long ranges thanks to the improved bullet coefficiency of the boat tail design. One of the reasons for this is the boat tail bullet’s longer length places its center of gravity more toward the middle of the bullet and thereby increasing its stability and accuracy.
- More retained long-range energy: Physics dictates that if we double the weight of an object in motion the kinetic energy is doubled. However, if we double the speed, or velocity, of the object we quadruple the energy. This means that because the boat tail bullet experiences less drag it retains more speed and then, therefore, delivers more downrange energy. This is an actual real-world benefit when hunting where long shots are common, if not the norm.
- For a given caliber and bullet weight, because of the longer design, boat-tail bullets shot from a rifle with a faster twist rifling will be more stable in flight.
- Reduced terminal performance: All things being equal, boat tail bullets may experience greater jacket and core separation on impact than flat nose bullets. This is simply because the tapered tail of a boat tail contains less lead than a flat tailed bullet. However, this is more of theoretical issue than a practical one and would still only be noticed in hunting applications.
- Boat tail bullets do not perform the same in all rifles. This is because boat tail bullet are designed for rifle barrels with faster twist barrels.
- Boat tail bullets are typically not as accurate as flat nose bullets at ranges under 200 to 250 yards.
When Should You use Boat Tail Ammo and When Not?
Now that we have answered the “what is boat tail ammo” question, it pays to know when and when not to use boat tails as compared to flat-tailed bullets. Boat tails perform better than flat nose bullets in both hunting and target shooting situations at ranges over 250 yards. At closer ranges flat nose bullets have a slight advantage in accuracy, however, the benefit typically won’t be noticeable in hunting situations. In short-range target shooting flat nose bullets will have the advantage.
Finally, it is worth noting that hollow point boat tails typically tend to be a little more accurate that solid nose bullets. While this probably won’t matter much in a hunting situation, in long range competition target shooting it may make the difference between finishing in first and third place.