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Is it your opinion that BT's are more accurate at any range ?
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Just like any other bullet component, you cannot definitely say that *ANY* boat tail bullet is going to be more accurate than *ANY* flat base bullet. Each gun is going to shoot some bullets better than others.
The Frisbee/football analogy above
seems to make sense, but really it doesn't. The reason a Frisbee or football wobbles as you throw it, is because you didnt throw it perfectly. Then, as it flies aerodynamic drag will cause it to fly in the most efficient way possible, which is without wobbling. Its not that the football gets "more accurate" as it flies, thats simply not possible. If its off target at close range, its going to be off target at long range. Same with bullets. Even though its wobbling right after you throw it, its still on its way to its target. If you throw it really badly, the wobble will stay with it all the way, if you throw it pretty good the wobble goes away. Its simply conservation of energy, nothing more.
SO why the myth?
It comes from a lack of understanding the relationship between MOA and BC.
Well, as we know, different guns will always shoot better with certain bullets shot at certain velocities. The key to load development is to find the velocity that the bullet you want to use shoots best at. If you take a random boat tail bullet and a random flat base bullet of the same weight and shoot them both at the same velocity, if your guns happens to shoot the FB bullet better at that velocity, its easy to make the mistake of thinking that the FB bullet shoots better at short range, while the BT bullet shoots better at long range.
WHY?
Because a Flat base bullets groups will open up faster at range than a boat tail, especialy in the wind, due to its high B.C. (the bt's)
In fact, its easy to make a neat little chart showing how a FB bullet is more accurate at short ranges and a BT bullet is more accurate at long ranges, without having to fudge the data at all.
All you have to do is select a FB bullet that starts out with smaller groups than the BT bullet at short range. Because the BT bullet has a higher BC, its going to have less wind drift down range, so shot side by side, even if the FB bullet STARTS with smaller groups, the BT
will eventually have smaller groups once the range gets out there, even if the difference in short range groups is fairly dramatic, because its (the BT) more aerodynamic. SO for example, start with a FB bullet that groups at 1/2" at 100 yards, and a BT bullet that groups at 1".The FB bullet is twice as accurate as the BT bullet. Out to 200-300 yards, the advantage the boat-tail has in bucking the wind doesnt have time to show so the FB bullets groups will still be smaller than the BT groups. But once you get past 200-300 yards, the BT bullet groups will start to get smaller than the FB bullet groups.
The key to remember here, is that its NOT that the BT bullets are getting more accurate, with range. thats simply not possible, Whats happening is that the FB bullets are getting LESSaccurate, due to its lower B/C, the wind will affect it more and more as distance gets greater and greater.
Its easy to see this by simply calculating the MOA at each range shot. What you will NOT see is the BT bullet shooting 2moa at 100 yards, then suddenly shrinking to 1moa at 400 yards. What will happen is that the MOA of BOTH FB and BT bullets is going to increase with range, but the FB will increase
faster.
It can easily give the illusion that the FB is better at short range and the BT is better at long range, but thats all it is, an illusion
created by bullet selection. Start with two bullets that are equally accurate at short range, and you will see the difference in groups between the BT and FB bullets increase even more dramatically than it did in the test where the FB bullet started out more accurate....
So to recap, If you
start with a FB bullet thats more accurate than the BT, then OF COURSE the FB bullet will be better at short range, becase it shoots better out of YOUR gun. Then as range increases, the more arodynamic BT bullet will eventualy end up with smaller groups than the FB. But its not because the BT is getting more accurate with range. Its because the FB is getting LESS accurate.
So yes, if a FB bullet shoots really well for you and you only shoot to 200 yards, then you
would be wasting your money buying a boat tail bullet that shoots just as well at 200 yards. Thats just commons sense...... But, that doesnt mean the FB bullet is inherently more accurate simply by virture of being a FB bullet. Its just means that
that particular FB bullet shoots really well out of your gun, and you dont shoot at long enough range for the disadvantages of a FB bullet to affect your groups.
Its certainly possible that its easier to find an accurate load with FB bullets, but its simply not true that BT bullets start out less accurate, then get more accurate later on down the line. They simply are less affected by wind. Again, its not that BT bullets get MORE accurate at long range, its that FB bullets get LESS accurate at range.