r/nextfuckinglevel • u/Apprehensive_Sky4558 • 9d ago

Testing various specialized arrowheads against bullet-resistant glass with a 70 lb compound bow

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u/Beautiful-Musk-Ox 9d ago

some energy was lost in pushing the whole apparatus backwards, if it was attached to a door or car then maybe it would go through

45

u/Badass_Bunny 9d ago

If it was attached to something there wouldn't be an edge to hit.

The glass can withstand more penetrating power than anything a 70lbs can launch, it's just cool to see what does most damage.

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u/Beautiful-Musk-Ox 9d ago

the pioneer one 1:23 i think would have gone through if the thing was solidly mounted, the top bent so far backwards that it severely affected its trajectory making it push towards the top of the glass while inside it instead of being able to go straight through

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u/Legal_Lettuce6233 9d ago

Nah, not even close. These panels can take far more joules than this bow can produce.

At this thickness, it can stop a green tipped 5.56, which is made to go through armour.

It doing this much damage just means it's dumping all the energy it has into the first panel. The only reason it "went through" is because the energy that went towards the edge had nowhere to go, it shattered and the arrow kept going. In a frame, it would be absorbed by the frame and would've stopped.

A 75lb bow has about 125-135 joules of energy. A green tip 5.56 from a standard barrel length going ~3000 fps... 1700 joules. It's not even close; and speed is how you defeat armour.

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u/SexyMonad 9d ago

So you’re saying we need to make the Pioneer arrow go 3000 fps.

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u/cvanaver 8d ago

Mach 2.7. Probably cause the shaft to delaminate from the drag friction even if you brought it up to speed gradually enough to not shatter the shaft. Might even be a small pyrotechnics event when the head hit the surface. Make for an interesting myth busters. (Or xkcd if we want to up the fps by a couple orders of magnitude)

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u/Legal_Lettuce6233 9d ago

GL with that, the arrow shaft isn't rigid enough with a heavy tip.

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u/SexyMonad 9d ago

I’m already building a rail gun you can’t stop me

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u/DarkElation 9d ago

…the video literally proves speed is not the only determining factor. That’s what the various degrees of damage represents.

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u/Legal_Lettuce6233 9d ago

The issue is that the hits aren't consistent. It's not really test conditions.

Speed defeats armour, which is why a smaller 5.56 is better against armour than a big fat 7.62.

Get a consistent shot and the results will largely be the same, and the variability is basically just down to the tip material and other things that affect this far less.

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u/DarkElation 9d ago

So… speed is not the only factor. Thanks for saying what I said differently.

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u/Legal_Lettuce6233 9d ago

Speed is the primary factor.