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Does the Bullet's Tip Melt While Going Through the Air?

maybe if you shot the bullet from space into the earths atmosphere and it melted upon re-entry......

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Does the Bullet's Tip Melt While Going Through the Air?

I have a friend that hunted African plains game with a 264 Win Mag that was designed to fire a 160gr soft pointed bullet at 4000fps. The bullet was so designed that at 400yds the lead tip would dissolve and force the air around to the base of the bullet and actually increase the velocity out to 1700yds with only a 4 inch drop in trajectory.

I've also got some beach front property in Montana for sale and a left handed crescent wrench that works on right hand bolts.

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Does the Bullet's Tip Melt While Going Through the Air?

Clearly there's a lot skepticism here but I've got to look at this scientifically.

Lead has a relatively low melting point, and I would imagine that it's theoretically possible for friction at supersonic speeds to raise surface temperatures significantly.

The question boils down to two things. First, would the temperature be high enough, and second, would it remain there long enough to cause degradation on anything greater than a microscopic level?

This may be one of those things where it's theoretically possible, but happens on such a small scale that it's negligible. I don't know that it could ever be measured, either, because any media used to stop the bullet would cause more friction damage than the air.

So if it's thoretically possible, effectively negligible and impossible to prove, the answer is simple -- grab another beer, kick the fire, and change the subject.

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Does the Bullet's Tip Melt While Going Through the Air?

Actually the Speer Mag Tip was designed because Speer, under Vernon Speer, took high speed photo's of bullet's leaving the barrel and the tip's were gone! It's probally not necessarily the air that generate's the heat but, the trip down the barrel. My guess would be that they don't really melt but rather get heated to a point where the small tip might wash off. Not really that uncommon. Take out your 22-250 and shoot some 50 gr Hornady SX's at a bit over 3500 fps and you'll be able to see some disinagrate in the air. A friend and I tried it when the bullet's first came out.

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Does the Bullet's Tip Melt While Going Through the Air?

There are several varmint bullets designed to disintegrate on impact. They are less likely to ricochet.
If fired at a velocity faster than they are rated for. They will disintegrate in mid trajectory. This is due to the extremely thin jacket, not the lead melting.
This would be a safety feature designed into the bullet and some very clever engineering.
All hunting bullets are rated to an optimal velocty range for performance. If the velocity is not reached or is exceeded. The bullet will not perform as it was designed. Hence, very little to no mushroom or disintegration.

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Does the Bullet's Tip Melt While Going Through the Air?

I'm not saying that the bullet is melting. I know that the jackets are very thin and with the trip down the barrel some heat is built, I don't know how much. But if something is not going on with the lead core, why isn't it reaching the target? I don't have any answer for this but it sure seem's that something is going on with the , light weight anyway, lead core that causes it to be disrupted also. If you were to try and fire a lead bullet from a rifle at 3000 fps, what do you think would happen? You won't find a load in any cast bullet book that will give it to you. Now I'm sure not going to be the one to test that, probally be some severe leading in the barrel.

What I do know is that this loss of the tip on firing is why Vernon Speer developed the Mag Tip bullet. And, they showed high speed photo's of bullet's in flight showing the absence of the tip. And it make's some sense as the ballistic tip bullet's seem to maintain velocity better, or so we're lead to believe. Why would that be other than it maintains it's balistic qualities better?

We have alway's been told that bullet's with deformed noses need be set aside and used for practice. Maybe so, maybe not, have you ever tried taking a bunch of ammo with deformed noses and shot then seriously? The theory that the tip melt's seems a bit far fetched to me but, I don't believe that nothing happen's either. Heated up led is easier to ding than unheated lead. It's possible that that is what's happening and the tip's are just washed off. Something to think about anyway.

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Does the Bullet's Tip Melt While Going Through the Air?

One more thought, The metal jacket has a higher melting point than the lead and is supported inside by the lead. Why would it fail in flight supported like it is? Supported as it is, pressure on the bullet is from the outside yet it fail's outward because it can't fail inward, the lead stop's it???????????

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Does the Bullet's Tip Melt While Going Through the Air?

At transonic or supersonic speeds, shock waves create intense localized differences in pressure on the surface. Not all of the air flowing across the surface is at uniform speed. On an airliner, for example, some parts of the jet may have supersonic airflow over them, even though the jet as a whole is still subsonic. On the other end, jet engines can't handle shock waves, so intakes on high-speed aircraft are designed to slow the airflow to subsonic speeds before it reaches the compressor blades.

In early attempts at supersonic flight, they lost a lot of aircraft as they approached Mach 1 and shock waves formed on control surfaces, causing loss of control.

Bottom line is that shock waves create sharp pressure deltas on the exterior of the bullet, and those pressure differences create stress on the surface. And of course, if any if those differences overcome the structural limits of the material, the resulting deformation, even if minute, transfers stresses elsewhere and things rapidly snowball out of control via catastrophic structural failure. Once structural failure interrupts the airflow, the bullet becomes unstable and forces move and multiply, making things even worse -- and your bullet comes apart like the Space Shuttle.

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Does the Bullet's Tip Melt While Going Through the Air?

expatriate. Would that explain the tip missing in flight and why the barrel doesn't lead with the missing tip's? After all, the tip is the only part of the bullet not contained by jacket material. And if you believe the photo's of the Speer bullet in flight, the tip is missing. Those adds were back in the early 70's and they weren't computer enhancing thing's then like they do now. Furthermore it would be a very expensive scam to pull just to sell a few more bullet's by a company already selling lot's of bullet's.

The purpose of the jacket has to be to hold the core together at high speed. Otherwise we'ed all still be shooting cast bullet's but at 3000 fps. This is interesting. Ever since those Speer adds, I've wondered at the necessity of good lead tip's on bullet's.

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Does the Bullet's Tip Melt While Going Through the Air?

I don't know that I can answer that, Don. For that matter, you have to wonder why a lead tip would fail but a plastic (sorry -- "advanced polycarbonate") ballistic tip wouldn't. That suggests there's something more than temperature at work. I can only assume it has something to do with the elasticity of the material or aerodynamic stresses on a potentially deformed or blunted point.

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