New ballistic body armor

DanHoward · 01-05-2009, 04:35 PM

Wearing a steel plate that has been perforated with holes seems to make any ballistic armour worn underneath more effective since it only has to resist fragments and not a solid bullet.

http://news.bbc.co.uk/2/hi/science/nature/7811567.stm

I was wondering how to determine GURPS stats for a composite body armour made of perforated bainite over kevlar?

Anthony · 01-05-2009, 05:19 PM

The usual purpose of hard/soft body armor layering is to have the hard outer layer degrade the bullet, spreading the force over a larger area where the soft layer absorbs it, so that aspect of the armor is unsurprising. I would be worried about this armor actually worsening the injury from rounds that do penetrate, by driving fragments of metal into the wound (this was apparently a problem with early bulletproof mail armor).

In GURPS, you would implement this stuff as a hard insert plate, just like any other, though it might have reduced DR vs crushing, and like most hard insert plates it's realistically semi-ablative. It also might be more random than normal for armor -- it looks like the hole size may be similar to the size of a bullet, so you could get significant variation depending on exactly how you hit (most likely, hole size is such that a bullet cannot actually fit through a hole, but even so different impact points would generate significantly different stresses on the bullet). Flechette rounds, if they ever come into common use, would have a good chance of shooting right through this armor. Might also be an issue with bullets with a hardened tungsten core, though those will generally shoot through body armor anyway.

doulos05 · 01-05-2009, 05:26 PM

Quote:

Originally Posted by DanHoward

Wearing a steel plate that has been perforated with holes seems to make any ballistic armour worn underneath more effective since it only has to resist fragments and not a solid bullet.

http://news.bbc.co.uk/2/hi/science/nature/7811567.stm

I was wondering how to determine GURPS stats for a composite body armour made of perforated bainite over kevlar?

I think the best way to represent that would either be to increase DR or provide a Armor Divisor... Divisor.

Bruno · 01-05-2009, 06:12 PM

Quote:

Originally Posted by doulos05

I think the best way to represent that would either be to increase DR or provide a Armor Divisor... Divisor.

That's Hardened. :D

Joseph Paul · 01-05-2009, 07:07 PM

Given how much they are touting the ductility of the bainite it may be very hard to get the insert to actually make fragments.

I suspect that what they mean by 'becomes a blunt fragment' is that the deflection of the bullet turns it enough that it is trying to go through the vest sideways.

Normally I hate randomizing armor values but this may be a situation where it makes sense.

1) Roll 1d6 to determine how many d6s to roll for additional DR.
If that seems a bit much make it 1d6-1 (...2,3 etc) minimum of 0d6. For those that think the plate may produce fragments a negative roll (ie 1d6-3 and a roll of 1 making a net of -2) is the number of additional a) dice of damage b) points of damage c) fragments with their own damage.

2) Roll 1d6 - 1-3 double DR of the soft component of the vest, 4-5 multiply DR of the vest by 1.5, on a 6 no change.

Anthony · 01-05-2009, 07:53 PM

Quote:

Originally Posted by Joseph Paul

Given how much they are touting the ductility of the bainite it may be very hard to get the insert to actually make fragments.

Did you look at the image in the article? It has a several holes in it.

bstubby · 01-05-2009, 08:32 PM

Umm, unless I missed something the article is talking about vehicle armor, not body armor. The fact that the material will fragment is a moot point; nothing is going to impart enough force to the fragment to pierce the underlying armor without being a catastophic kill anyway.

Joseph Paul · 01-05-2009, 09:13 PM

Quote:

Originally Posted by Anthony

Did you look at the image in the article? It has a several holes in it.

Yes I did but the article does not mention fragmentation being a problem nor does the picture show that the holes are not made by the purposeful removal of material after the round broke part of the connecting web.

Did you notice that I included an option for fragmentation in the quickie statting that I did? Sub-option c) of option 1.

bstubby- you are right it is slated for vehicles but Dan wanted to know what people's thoughts of using it as a body armor were. At least that is what I got from his post.

Perforated hard steel plate may be a boon to ESA equipped vehicles as that would allow venting of the discharge.

DanHoward · 01-06-2009, 02:49 AM

Yes I know the article talked about vehicle armour. My question was whether the same combination would make a useful body armour. Perhaps using perforated bainite inserts instead of ceramic ones.

Hai-Etlik · 01-06-2009, 04:18 AM

Quote:

Originally Posted by DanHoward

Yes I know the article talked about vehicle armour. My question was whether the same combination would make a useful body armour. Perhaps using perforated bainite inserts instead of ceramic ones.

The article didn't provide enough information to determine that. If it were practical for body armour, I would think they would mention it. But even determining reasonable stats for vehicles would be tricky given just a news article.

01-05-2009, 04:35 PM	#1
DanHoward Join Date: Mar 2005 Location: Maitland, NSW, Australia	New ballistic body armor Wearing a steel plate that has been perforated with holes seems to make any ballistic armour worn underneath more effective since it only has to resist fragments and not a solid bullet. http://news.bbc.co.uk/2/hi/science/nature/7811567.stm I was wondering how to determine GURPS stats for a composite body armour made of perforated bainite over kevlar?

01-05-2009, 05:19 PM	#2
Anthony Join Date: Feb 2005 Location: Berkeley, CA	Re: New ballistic body armor The usual purpose of hard/soft body armor layering is to have the hard outer layer degrade the bullet, spreading the force over a larger area where the soft layer absorbs it, so that aspect of the armor is unsurprising. I would be worried about this armor actually worsening the injury from rounds that do penetrate, by driving fragments of metal into the wound (this was apparently a problem with early bulletproof mail armor). In GURPS, you would implement this stuff as a hard insert plate, just like any other, though it might have reduced DR vs crushing, and like most hard insert plates it's realistically semi-ablative. It also might be more random than normal for armor -- it looks like the hole size may be similar to the size of a bullet, so you could get significant variation depending on exactly how you hit (most likely, hole size is such that a bullet cannot actually fit through a hole, but even so different impact points would generate significantly different stresses on the bullet). Flechette rounds, if they ever come into common use, would have a good chance of shooting right through this armor. Might also be an issue with bullets with a hardened tungsten core, though those will generally shoot through body armor anyway.

01-05-2009, 07:07 PM	#5
Joseph Paul Custom User Title Join Date: Oct 2007 Location: Indianapolis, IN	Re: New ballistic body armor Given how much they are touting the ductility of the bainite it may be very hard to get the insert to actually make fragments. I suspect that what they mean by 'becomes a blunt fragment' is that the deflection of the bullet turns it enough that it is trying to go through the vest sideways. Normally I hate randomizing armor values but this may be a situation where it makes sense. 1) Roll 1d6 to determine how many d6s to roll for additional DR. If that seems a bit much make it 1d6-1 (...2,3 etc) minimum of 0d6. For those that think the plate may produce fragments a negative roll (ie 1d6-3 and a roll of 1 making a net of -2) is the number of additional a) dice of damage b) points of damage c) fragments with their own damage. 2) Roll 1d6 - 1-3 double DR of the soft component of the vest, 4-5 multiply DR of the vest by 1.5, on a 6 no change. __________________ Joseph Paul

01-05-2009, 08:32 PM	#7
bstubby Join Date: Oct 2008 Location: Austin, TX	Re: New ballistic body armor Umm, unless I missed something the article is talking about vehicle armor, not body armor. The fact that the material will fragment is a moot point; nothing is going to impart enough force to the fragment to pierce the underlying armor without being a catastophic kill anyway.

01-06-2009, 02:49 AM	#9
DanHoward Join Date: Mar 2005 Location: Maitland, NSW, Australia	Re: New ballistic body armor Yes I know the article talked about vehicle armour. My question was whether the same combination would make a useful body armour. Perhaps using perforated bainite inserts instead of ceramic ones.