Boat-tailed bullets were developed to increase the ballistic coefficient (BC) of the projectile in flight, with a secondary effect that increased the retained energy down-range.
Usually, but not always, they have long, thin noses and a low-drag profile, but some designed push the definition of ‘boat tail’ particularly the lighter projectiles at the lower end of the ballistic scale.
There is much debate as to when and where boat-tailed bullets should be used.
After many years of use, I have concluded that they start to earn their keep at somewhere about 250 metres from the muzzle.
Yes, I know you can buy a big argument about the ethics of long-range shooting as such, particularly where live game is concerned. You have to make up your mind about the ethics as such, it’s always a controversial subject.
Some have questioned whether the fine needle-point low drag nose will open up in animal flesh. All I can say is that I and some friends have used them for more than 25 years without any hint of failure. From the few autopsies we carried out in the early days it would appear that such a needle-nose projectile penetrates an unknown distance and then disintegrates.
We have used them in several .22-calibre cartridges with weights between 55gn and 80gn, but there were also some in .270s which worked as advertised.
Even a small change in nose profile that increases the BC will show up down range with better retained velocity and energy. The truth of this statement can be proven with any ballistic table.
Certainly, to extend the useable range of any particular cartridge, boat-tails are a useful addition.
The other issue relating to projectile BC relates to wind drift. The amount of drift is directly related to the initial muzzle velocity and the BC of the projectile.
The higher the BC, the less the drift at any given range.
Perhaps the one downside relating to boat-tailed projectiles is that they can be fussy about seating depth. To find the best seating depth, Berger’s website suggests creating four loads, with projectiles that sit 0.010”, 0.050” 0.090” and 0.130” respectively from the lands, then seeing which one groups best.
Boat-tailed projectiles are very useful for all long-range work as they tend to be heavy and long in relation to calibre, but you need to be sure that your barrel has the correct twist rate to stabilise them.
Some people think boat-tailed projectiles are fussy and difficult to load, but I disagree. I have used them for nearly 40 years without any problems and there are still many in the reloading cupboard.
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