# Lorica Hamata vs Lorica Segmentata

## Which type of armour do you think was the best?

• ### Lorica Segmentata

• Total voters
61

• O

#### Olleus

Deceleration decreases force, it doesn't create force. Deceleration only means the object is slowing down, that in itself wouldn't hurt you. In fact it would help the guy being hit, as that means the arrow wouldn't be as powerful when it hits him.
I don't have the time to refute everything you just said, but that is completely false. It is a fundamental misunderstanding of what force and acceleration is. I learnt in middle school physics that any change of velocity (speed) is an acceleration. That's one of the few things taught in middle school physics which is absolutely accurate. Any acceleration of an object is caused by a force. I also specifically explained that the force that hurt you isn't the force that causes the deceleration in flight, it's the force that causes the arrow to decelerate rapidly upon hitting something (technically, the reaction force of Newton's 3rd). I can't explain this any more clearly than that to you.

You don't understand the very basic physics, please try and learn it, and don't press points about the physics until you do.

Also please stop trying to lecture me on physics, you're wasting your time and embarrassing yourself further. I have 10 years education in physics, including two masters and a PhD in it, and am writing this post from my office in a physics research institute. You're one of the posters I respect the most on here but you seem to be deliberately losing credibility as fast as you can.

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#### aggienation

I don't have the time to refute everything you just said, but that is completely false. It is a fundamental misunderstanding of what force and acceleration is. I learnt in middle school physics that any change of velocity (speed) is an acceleration. That's one of the few things taught in middle school physics which is absolutely accurate. Any acceleration of an object is caused by a force. I also specifically explained that the force that hurt you isn't the force that causes the deceleration in flight, it's the force that causes the arrow to decelerate rapidly upon hitting something (technically, the reaction force of Newton's 3rd). I can't explain this any more clearly than that to you.

You don't understand the very basic physics, please try and learn it, and don't press points about the physics until you do.

Also please stop trying to lecture me on physics, you're wasting your time and embarrassing yourself further. I have 10 years education in physics, including two masters and a PhD in it, and am writing this post from my office in a physics research institute. You're one of the posters I respect the most on here but you seem to be deliberately losing credibility as fast as you can.

• #### Openminded

Also please stop trying to lecture me on physics, you're wasting your time and embarrassing yourself further. I have 10 years education in physics, including two masters and a PhD in it, and am writing this post from my office in a physics research institute. You're one of the posters I respect the most on here but you seem to be deliberately losing credibility as fast as you can.

• #### HackneyedScribe

I don't have the time to refute everything you just said, but that is completely false. It is a fundamental misunderstanding of what force and acceleration is. I learnt in middle school physics that any change of velocity (speed) is an acceleration.
I was using the layman definition that I already told you of, I was speaking in terms of penetration, I thought you were too but apparently not. I gave the official definition and the laymen definition that's been going on in the net, I assumed you knew which one I was using considering I was clearly speaking in terms of penetration.

That's one of the few things taught in middle school physics which is absolutely accurate. Any acceleration of an object is caused by a force. I also specifically explained that the force that hurt you isn't the force that causes the deceleration in flight, it's the force that causes the arrow to decelerate rapidly upon hitting something (technically, the reaction force of Newton's 3rd). I can't explain this any more clearly than that to you.
In that case you are talking about shock, not penetration. I thought you were talking about penetration. You should have figured that out as I said:
force is hardly the optimal way to calculate penetration power of an arrow.
If you are talking about shock then that's a different story, but I was talking about penetration.

You don't understand the very basic physics, please try and learn it, and don't press points about the physics until you do.

Also please stop trying to lecture me on physics, you're wasting your time and embarrassing yourself further. I have 10 years education in physics, including two masters and a PhD in it, and am writing this post from my office in a physics research institute. You're one of the posters I respect the most on here but you seem to be deliberately losing credibility as fast as you can.
Which part of my equation is wrong then? I used the exact same equation you provided, and the result was given. If you have a different result for energy and momentum than show it. If you have a different result for impact area, such as proving that the test hit the armor with something BESIDES an unhardened bodkin, than show it. All you did was assume a lot of things about the test that wasn't correct. Whether you have a PHD in physics doesn't change that.

In summary, the test used a cherioballista which could shoot a 102 g bolt at 47 m/sec (113 joules and momentum of 4.8).
When the same cheiroballista was tested against the lorica segmentata, it used a 70 gram bolt with an unhardened bodkin arrowhead at a distance of 50 meters. Judging from the picture, the arrowhead have an angle of roughly 30 degrees which is not atypical for an arrowhead.
The lorica segmentata was set up on a "dummy legionary" with at least some padding.
The lorica segmentata had steel girth hoops of 1.25 mm thick, whereas authentic ones would have girth hoops closer to .7 mm thick, and the metallurgy would be equivalent to "mild steel".
The test penetrated the first girth hoop, and severely dented the overlapping one underneath it.

-You brought up force, and you are using it to talk about shock. I thought you were using it to talk about penetration, which is why there is a misunderstanding. In fact, you should have figured it out because I already told you "I gave you the alternative "layman" version because the official definition is hardly the best way to calculate the penetration power of an arrow, as it's just a combination of acceleration and mass."
-But besides that, you provided the equations for energy and momentum, which is exactly the same equations I used. Show me just where my calculations are off, don't just wave your PHD in my face. Show me precisely where the calculation are off. Did you use the same equation to get a number (102 gram bolt, 47 m/s) besides 113 joules and a momentum of 4.8?
-You talk about the importance of impact area, I already told you that the armor was impacted by an unhardened bodkin point, which is not exactly an atypical arrowhead. How in the world do you think an unhardened bodkin point caused an atypical impact area compared to other generic arrowheads? Don't throw your PHD in my face, explain precisely why you would think an unhardened bodkin point hitting the armor would have an atypical impact area compared to generic military arrowheads. In fact bodkin points are one version of generic military arrowheads.

For someone with a PHD and a physics office, I expect more hard data and less vaunting. So far you listed the following variables:
Force <---- I'm talking about penetration, you admit you are using it to talk about something else. Ergo irrelevant.
Impact area <------ I already told you that the arrowhead was an unhardened bodkin, you have not explained how that would give a different impact area than other generic military arrowheads, especially considering bodkins are one type of generic military arrowheads
Energy <----- I used the exact same equation you used, if you arrived at a different number then show it.
Momentum <----- I used the exact same equation you used, if you arrived at a different number then show it
Impact Energy <----- I may have used initial energy rather than impact energy, but this means I'm being generous to the armor being tested. This is because initial energy of an arrow is greater than impact energy, and if you don't know that then I would doubt your PHD or even high school degree for that matter.

I may not be a major in physics, but I do have an advanced math degree with my own share of physics so I'm sorry, but your PHD in itself won't impress me. Show me the actual math to impress me, because so far I haven't seen you do any calculations to prove your point. So why don't you show some actual hard data, I'm not hiding behind my degree why are you? So hard data/calculations otherwise the loss in respect is mutual.

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#### aggienation

I was using the layman definition that I already told you of, I was speaking in terms of penetration, I thought you were too but apparently not. I gave the official definition and the laymen definition that's been going on in the net, I assumed you knew which one I was using considering I was clearly speaking in terms of penetration.

In that case you are talking about shock, not penetration. I thought you were talking about penetration. You should have figured that out as I said:
force is hardly the optimal way to calculate penetration power of an arrow.
If you are talking about shock then that's a different story, but I was talking about penetration.

Which part of my equation is wrong then? I used the exact same equation you provided, and the result was given. If you have a different result for energy and momentum than show it. If you have a different result for impact area, such as proving that the test hit the armor with something BESIDES an unhardened bodkin, than show it. All you did was assume a lot of things about the test that wasn't correct. Whether you have a PHD in physics doesn't change that.

In summary, the test used a cherioballista which could shoot a 102 g bolt at 47 m/sec (113 joules and momentum of 4.8).
When the same cheiroballista was tested against the lorica segmentata, it used a 70 gram bolt with an unhardened bodkin arrowhead at a distance of 50 meters. Judging from the picture, the arrowhead have an angle of roughly 30 degrees which is not atypical for an arrowhead.
The lorica segmentata was set up on a "dummy legionary" with at least some padding.
The lorica segmentata had steel girth hoops of 1.25 mm thick, whereas authentic ones would have girth hoops closer to .7 mm thick, and the metallurgy would be equivalent to "mild steel".
The test penetrated the first girth hoop, and severely dented the overlapping one underneath it.

-You brought up force, and you are using it to talk about shock. I thought you were using it to talk about penetration, which is why there is a misunderstanding. In fact, you should have figured it out because I already told you "I gave you the alternative "layman" version because the official definition is hardly the best way to calculate the penetration power of an arrow, as it's just a combination of acceleration and mass."
-But besides that, you provided the equations for energy and momentum, which is exactly the same equations I used. Show me just where my calculations are off, don't just wave your PHD in my face. Show me precisely where the calculation are off. Did you use the same equation to get a number (102 gram bolt, 47 m/s) besides 113 joules and a momentum of 4.8?
-You talk about the importance of impact area, I already told you that the armor was impacted by an unhardened bodkin point, which is not exactly an atypical arrowhead. How in the world do you think an unhardened bodkin point caused an atypical impact area compared to other generic arrowheads? Don't throw your PHD in my face, explain precisely why you would think an unhardened bodkin point hitting the armor would have an atypical impact area compared to generic military arrowheads. In fact bodkin points are one version of generic military arrowheads.

For someone with a PHD and a physics office, I expect more hard data and less vaunting. So far you listed the following variables:
Force <---- I'm talking about penetration, you admit you are using it to talk about something else. Ergo irrelevant.
Impact area <------ I already told you that the arrowhead was an unhardened bodkin, you have not explained how that would give a different impact area than other generic military arrowheads, especially considering bodkins are one type of generic military arrowheads
Energy <----- I used the exact same equation you used, if you arrived at a different number then show it.
Momentum <----- I used the exact same equation you used, if you arrived at a different number then show it
Impact Energy <----- I may have used initial energy rather than impact energy, but this means I'm being generous to the armor being tested. This is because initial energy of an arrow is greater than impact energy, and if you don't know that then I would doubt your PHD or even high school degree for that matter.

I may not be a major in physics, but I do have an advanced math degree with my own share of physics so I'm sorry, but your PHD in itself won't impress me. Show me the actual math to impress me, because so far I haven't seen you do any calculations to prove your point. So why don't you show some actual hard data, I'm not hiding behind my degree why are you? So hard data/calculations otherwise the loss in respect is mutual.
Did anyone actually think you'd humbly back down? No.

Ego, its a hell of a drug.

• #### HackneyedScribe

Yes, because I don't hide behind my degree as leverage while doing absolutely zero calculations. I provide hard data instead. Can you and Olleus then describe just where my calculations went wrong, specifically? Or if anyone claim they're a PHD, without being able to say just where the calculations are off, then that's good enough? Even if I'm wrong, I expect to know where I'm wrong. Claiming you have a math background without giving the specifics is useless in that regard.

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#### aggienation

Yes, because I don't hide behind my degree as leverage while doing absolutely zero calculations. I provide hard data instead. Can you and Olleus then describe just where my calculations went wrong, specifically? Or if anyone claim they're a PHD, without being able to say just where the calculations are off, then that's good enough?
Olleus spent two pages showing where you're wrong and gave up because your ego and ignorance wouldn't admit it. What is the point? Spend 50 pages doing it? Is he supposed to teach you physics? Why bother, you'll NEVER admit you were wrong. Because your ego wont allow it.

• #### HackneyedScribe

The two pages only had him showing some variables, not how they affect my conclusion.

I already broke down Olleus' variables, and I will copy them to you again one by one:
Force <---- I'm talking about penetration, you admit you are using it to talk about something else. Ergo irrelevant.
Impact area <------ I already told you that the arrowhead was an unhardened bodkin, you have not explained how that would give a different impact area than other generic military arrowheads, especially considering bodkins are one type of generic military arrowheads
Energy <----- I used the exact same equation you used, if you arrived at a different number then show it.
Momentum <----- I used the exact same equation you used, if you arrived at a different number then show it
Impact Energy <----- I may have used initial energy rather than impact energy, but this means I'm being generous to the armor being tested. This is because initial energy of an arrow is greater than impact energy

Ergo out of his two page explanation, where was I wrong, specifically? He used those two pages to do what? Explain that a squash ball would have a different impact area than an arrow? True, but I'm not using the test to show what happens if the armor was struck by a squash ball. Nor am I using the test to show what happens if the armor was struck by the sword, nor whatever two page worth of analogies he made. I'm only using the test to show what happens if the armor was struck by an arrowhead, because the test struck the armor with a bodkin arrowhead, which was a pretty generic military arrowhead. Now if I missed some other variable he brought up which is relevant to armor penetration, then quote that part. Or for the variables shown above, show how I was wrong in my calculations. I backed off when I was wrong before, as long as people can specifically show me where I was wrong. And if you can't do that, then it's not ego, it's just math.

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• #### HackneyedScribe

I already broke down Olleus' variables, and I will copy them to you again one by one:
Force <---- I'm talking about penetration, you admit you are using it to talk about something else. Ergo irrelevant.
Impact area <------ I already told you that the arrowhead was an unhardened bodkin, you have not explained how that would give a different impact area than other generic military arrowheads, especially considering bodkins are one type of generic military arrowheads
Energy <----- I used the exact same equation you used, if you arrived at a different number then show it.
Momentum <----- I used the exact same equation you used, if you arrived at a different number then show it
Impact Energy <----- I may have used initial energy rather than impact energy, but this means I'm being generous to the armor being tested. This is because initial energy of an arrow is greater than impact energy
I forgot that Olleus also mentioned padding/leeway. But as I said, the test was conducted with this already in mind. One of Alan Wilkin's students was present in the test and he stated this:
A set of segmentata was set up on a stand and padded out to produce something which was hoped to approximate the resistance produced by a human body. A three span bolt was shot at it over a distance of 38 metres. The bolt struck the front of the armour on the overlap of two girdle plates. It penetrated the outer plate and stuck in the inner plate, meaning that technically it did not penetrate the cuirass. However, the force of the impact pushed the plates inward to the extent that even if a padded garment (a subarmalis) had been worn the wearer would probably have received fatal internal injuries.

So again:
Olleus mentioned impact area in order to invalidate the test. The article say that the tested armor was struck by an unhardened bodkin, so it represents the impact area of the typical arrowhead considering bodkins were pretty generic arrowheads as far as military arrowheads go.
Olleus mentined that absence of padding/leeway would invalidate the test. The test did address padding and put the armor on a dummy legionnaire and a stand, to approximate the resistance produced by a human body
He mentioned Energy and provided the equation, and it's the same equation I used. Now people had plenty of opportunity to show if I miscalculated.
He mentioned Momentum and provided the equation, and it's the same equation I used. Now people had plenty of opportunity to show if I miscalculated.
He mentioned I should use Impact Energy rather than Initial Energy. True, but Impact Energy is unavailable, and we know that Initial Energy of a projectile must be greater than its impact energy, ergo by using Initial Energy I am being generous to the armor, making it sound like it was struck by a more powerful projectile than what the armor was actually struck by.

So mentioning that Olleus has a PhD would change the above, how? Am I supposed to believe that because Olleus has a PhD, Alan Wilkins was lying when he said that the test used an unhardened bodkin point? Am I supposed to believe that because Olleus has a PhD, Alan Wilkin's student was lying when he said that their test used padding underneath the armor? His PhD have absolutely no weight regarding whatever assumptions he had about Alan Wilkin's test.

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