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Personally, I don't worry about that highly technical stuff, as long I can shoot decent groups (of 1inch or less @ 100 yds) with my reloads I'm happy, I use boat-tail bullets 'cause they seat so easy, but hey, that's just me.
 

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Boat tails shed velocity more slowly, and are more accurate at long range.

I dunno why, and really don't care!:p
 

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Go ahead. Believe that the aerodynamic forces of drag are solely based on what happens at the front end of the bullet. But for decades on match shooting ranges boattail bullets shoot flatter and display better accuracy and crosswind bucking ability.

Also, consider the effects in long range when the bullet is in transonic phase and that shockwave changes and the vacuum behind the bullet begins to close. Within the ranges that a bullet remains supersonic you may not see as much effect, but if you need to reach a little further you will.

if your shots are all within the supersonic envelope of bullet trajectory, you may not see any practical benefit to a boattail. I& you are trying to cut 10 rings and x rings at 1,000 yards with Service caliber rifles, (.308, and .30-06) it may be worthwhile.
 
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I'm an engineer and studied fluid dynamics...

When the air flows on the boat tail, it exerts a tangential force "forward" on the bullet.

With flat base bullets, there's not that tangential force benefit.

Visualize air pushing from the sides of the bullet towards the middle at the base.
 

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I'm an engineer and studied fluid dynamics...

When the air flows on the boat tail, it exerts a tangential force "forward" on the bullet.

With flat base bullets, there's not that tangential force benefit.

Visualize air pushing from the sides of the bullet towards the middle at the base.
The eddy in the current of air, IOW, yes?
 

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The eddy in the current of air, IOW, yes?
Yes. Think of the trailing edge of an airplane wing. When air flows over the surfaces, there are speed /pressure differences, and results in "lift forces". With a bullet, you get a linear force benefit / and we shooters get the benefit of "retains velocity better".
 

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He seems to be saying that no air flows past the shockwave and around the bullet, but that is not true. If it were, supersonic aircraft would fall out of the sky since the shockwaves form not only on the nose but the leading edges of the wings as well. No air over the wings, no lift.

A shockwave is just a compressed zone of the medium the object is traveling through. Supersonic shockwaves are on the order of about 0.001" thick, but air does not just stop flowing over the object. As speed continues to increase, the shockwaves will angle back at steeper relative angles. If speeds are high enough (far beyond the velocities attainable from a rifle) it is possible the shockwave could intersect with the bullet's surface on or near the ogive and that would create potential stability issues. In fact, we often talk about bullets becoming unstable once it drops from supersonic and goes transonic. Interestingly, the same bullet fired at subsonic speeds would be stable, but transonic speeds are where the air on some portion of the bullet is still moving at supersonic speeds while the bullet itself is subsonic. The regime is what causes instability as it changes the center of pressure, center of gravity, and bullet spin rate relationship.

Boat tails increase aerodynamic slipperiness by reducing the area at the tail of the bullet were turbulence occurs. The larger the area of turbulence, the more drag. This is why race cars and other vehicles use various splitters and duct shapes on the underside and at the rear to try to get the upper, lower, and side flow across the vehicle to merge smoothly back together at the rear (i.e. create as little turbulence as possible). Turbulence is drag.
 
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