← Autodidact Archive · Original Dissent · Faust
Thread ID: 16650 | Posts: 22 | Started: 2005-02-08
2005-02-08 04:10 | User Profile
Performance of Miltary Rifles 3.5mm steel plate
The 7.62 Nato(.308win) Ball M118 can penetrate the 3.5 steel plate at 800 yars. The 5.56 Nato(.223) Ball M855 can penetrate the 3.5 steel plate at 700 yars. The .30-06 Ball M2 can penetrate the 3.5 steel plate at 500 yars.
2005-02-08 04:20 | User Profile
7.62 Nato, 7.62x39mm, and 5.56 Nato Kinetic Engery in foot pounds.
2005-02-16 05:26 | User Profile
[QUOTE=Faust]Performance of Miltary Rifles 3.5mm steel plate
The 7.62 Nato(.308win) Ball M118 can penetrate the 3.5 steel plate at 800 yars. The 5.56 Nato(.223) Ball M855 can penetrate the 3.5 steel plate at 700 yars. The .30-06 Ball M2 can penetrate the 3.5 steel plate at 500 yars.[/QUOTE]
I find that hard to believe that the .308 can penetrate 3.5 inches of steel at 800 yards. Nor can I believe the same for the other too. I will have to do some tests on my own to confirm this.
2005-02-16 06:55 | User Profile
[QUOTE=ZeaL]I find that hard to believe that the .308 can penetrate 3.5 inches of steel at 800 yards. Nor can I believe the same for the other too. I will have to do some tests on my own to confirm this.[/QUOTE] Millimeters, dude -- not inches. :)
In any case, there are many different kinds of steel, and some will be penetrated more readily than others. They're talking about mild steel here as opposed to carpenter steel or some really tough alloy.
2005-02-16 13:39 | User Profile
Angler,
Yes Millimeters, not inches. I find a non steel core bullet going right though a 3.5mm steel plate at 800 yards pretty pretty impressive. It would right though any body armor around at close range.
More on 7.62-mm (.308win) M118 Ball cartridge
[QUOTE]The M118 Special Ball cartridge is used in the M14 Series, M21, M24, and M40A1 weapons. The sniper uses the 7.62-mm special ball (M118) ammunition with the sniper weapon system. The sniper must rezero the weapon each time he fires a different type or lot of ammunition. This information should be maintained in the sniper data book.
The 7.62-mm special ball (M118) bullet consists of a gilding metal jacket and a lead antimony slug. It is a boat-tailed bullet (rear of bullet is tapered) and weighs 173 grains. The tip of the bullet is not colored. The base of the cartridge is stamped with the year of manufacture and a circle that has vertical and horizontal lines, sectioning it into quarters. Its spread (accuracy standard) for a 10-shot group is no more than 12 inches at 550 meters (fired from an accuracy barrel in a test cradle).
The 7.62-mm M82 blank ammunition is used during sniper field training. It provides the muzzle blast and flash that can be detected by trainers during the exercises that evaluate the sniper's ability to conceal himself while firing his weapon.
Regular 7.62-mm ball ammunition should be used only in an emergency situation. No damage will occur to the barrel when firing regular 7.62-mm ball ammunition. The M3A scope's bullet drop compensator is designed for M118 special ball, and there will be a significant change in zero. Therefore the rifle will not be as accurate when firing regular 7.62-mm ball ammunition. The 7.62-mm ball ammunition should be test fired and the ballistic data recorded in the data book. [/QUOTE]
2005-02-17 02:33 | User Profile
performance is one thing, being able to take advantange of it is another. Somewhere after 300yds, the ability of a rifleman to engage targets smaller than a trashcan becomes a skill that takes time to learn and practice to master.
2005-02-17 02:43 | User Profile
JoseyWales,
Very true. Even the notion of snipers getting kills out that far happens more in bad movies than in the field.
2005-02-17 04:41 | User Profile
Come on guys, 300 yards? Even with my M-1 I can make that shot without a scope.
2005-02-17 08:02 | User Profile
Here's an interesting chart from a company that provides laminated ballistic glass. Unfortunately, it doesn't tell you where the 5.56 steel core (M855) stands, but we can assume it's above 5.56 lead core (M193).
Note that lead core 5.56 (M193) penetrates just as well in this material as lead core 7.62x51 (M80) and even non-AP .30-06 (M2). The small diameter of the .223 bullet and its high velocity undoubtedly make up for its lower power. Also note that 7.62x39 API rounds have devastating penetration ability.
It's worth remembering, though, that relative penetration ability varies among materials. Everyone knows, for example, that a .308 will penetrate a tree trunk much more deeply than a 5.56, even though the 5.56 holds its own against the .308 when it comes to ballistic glass.
[img]http://www.firstdefense.com/html/Ballistic_threat_Levels.gif[/img]
Source: [url]http://www.firstdefense.com/html/default_faqs.htm[/url]
2005-02-17 09:06 | User Profile
Ah, here's what I was really looking for: body armor threat levels as ranked by the National Institutes of Justice.
The entire chart can be found here: [url]http://www.pinnaclearmor.com/new/ballistic_chart.html[/url]
Here are the rifle caliber threat levels (I don't know what the "+ 100-0" means -- anyone have any ideas?):
Level III
7.62 x 63 mm 180 GR, SP.........................................2540 ft./sec. + 100-0 7.62 x 54 mm 147 GR, FMJ........................................2786 ft./sec. + 100-0 7.62 x 54 mm 180 GR, FMJ........................................2630 ft./sec. + 100-0 7.62 x 51 mm 148 GR, FMJ........................................2750 ft./sec. + 100-0 7.62 x 39 mm 150 GR, FMJ........................................2400 ft./sec. + 100-0 5.45 x 39 mm 54 GR, FMJ..........................................3000 ft./sec. + 100-0 5.56 x 45 mm 55 GR, FMC.........................................3000 ft./sec. + 100-0
Level IV
7.62 x 63 mm 166 GR, M2 AP.....................................2850 ft./sec. + 100-0 7.62 x 54R mm 147 GR, steel case, mild steel core.........2723 ft./sec. + 100-0 7.62 x 51 mm 151 GR, M61 AP...................................2800 ft./sec. + 100-0 7.62 x 39 mm 122 GR, steel case mild steel core...........2300 ft./sec. + 100-0 5.56 x 45 mm 62 GR, M855 (SS109 green tip)...............3200 ft./sec. + 100-0
2005-02-17 17:32 | User Profile
A level III is going to stop a 147 grain 7.62x54R moving at near 2800 FPS and a 30-06 AP going 2850 is going to be stopped by a level IV? The same round that goes through nearly 2 inches of ballistic glass? Maybe if it hits the trauma plate, but that doesn't seem possible on a Kevlar vest that a man could wear and still move around in. Plus, none of that is taking into account blunt trauma. Even if the vest held up, I'll bet the impact of a 7.62x54R to the chest is going to do you some major damage, even if it doesn't kill you, which seems pretty likely.
The "+ 100-0" might refer to an allowable velocity spread during testing?
2005-02-17 18:10 | User Profile
MadScienceType,
Yes, I am not sure buy the claim a Kevlar vest will stop a 30-06 AP. And you said, the blunt trauma would kill or do a lot of damage. I have read stories of Cops having had almost every rib broken by handguns hittting vests. In many cases vest do save lives, but the person is still put out of action.
Also people tend not wear the trauma plate. They just to heavy.
[QUOTE]A level III is going to stop a 147 grain 7.62x54R moving at near 2800 FPS and a 30-06 AP going 2850 is going to be stopped by a level IV? The same round that goes through nearly 2 inches of ballistic glass? Maybe if it hits the trauma plate, but that doesn't seem possible on a Kevlar vest that a man could wear and still move around in. Plus, none of that is taking into account blunt trauma. Even if the vest held up, I'll bet the impact of a 7.62x54R to the chest is going to do you some major damage, even if it doesn't kill you, which seems pretty likely.[/QUOTE]
That sounds right. I do not know for sure. [QUOTE]The "+ 100-0" might refer to an allowable velocity spread during testing?[/QUOTE]
2005-02-17 18:19 | User Profile
Angler,
Yes an interesting chart. Thanks for posting it. But it does not have 7.62-mm (.308win) M118 Ball cartridge. 5.56mm may penetrate, but it does not much after that. 7.62-mm (.308win) M118 Ball is better than 5.56 steel core (M855). Also it does not tell us how far the gun was when fired. Also most of time you do not need "TRANSPARENT ARMOR."
[QUOTE]The 7.62 Nato(.308win) Ball M118 can penetrate the 3.5 steel plate at 800 yars. The 5.56 Nato(.223) Ball M855 can penetrate the 3.5 steel plate at 700 yards[/QUOTE]
2005-02-18 01:43 | User Profile
The technological development of the 7.62 NATO ball essentially stopped in the early 70's. Image developing it to the degree of the much more modern 5.56 M855.
2005-02-18 07:58 | User Profile
[QUOTE=MadScienceType]A level III is going to stop a 147 grain 7.62x54R moving at near 2800 FPS and a 30-06 AP going 2850 is going to be stopped by a level IV? The same round that goes through nearly 2 inches of ballistic glass? Maybe if it hits the trauma plate, but that doesn't seem possible on a Kevlar vest that a man could wear and still move around in. Plus, none of that is taking into account blunt trauma. Even if the vest held up, I'll bet the impact of a 7.62x54R to the chest is going to do you some major damage, even if it doesn't kill you, which seems pretty likely. As far as I know, all Level III and Level IV body armor is in the form of hard plates (usually steel or ceramic) that are inserted into vest pockets sewn into vests for that purpose. I've looked around quite a bit, but I've never seen "soft" armor that provided more than Level IIIA protection (enough to stop subgun rounds). Rifle plates are rigid enough to absorb most of the blunt trauma -- I'm pretty sure they have to do that as well as prevent penetration in order to qualify for the appropriate NIJ standard. Only a certain amount of what they call "backface deformation" is allowed. I don't think getting shot by any of those rounds would be pleasant even if a rifle plate stopped it, but it might still be possible to gain one's senses after a moment and then return fire.
The moral as I see it is (1) those who don't have good body armor should buy it ASAP before it gets banned (it WILL be banned eventually), and (2) if you're ever in a firefight with SWAT pigs, aim at body parts other than the chest!
The "+ 100-0" might refer to an allowable velocity spread during testing?[/QUOTE]That does make sense, but they wrote it a bit funny if that's what they meant. They should have written something like "+ or - 100" to make it clearer.
2005-02-18 17:43 | User Profile
Angler,
Gotcha. I thought they were making these claims for soft armor, which explains my incredulity. Does that site whose ballistic table you displayed sell to "civilians" or do they only purvey to the King's Men?
2005-02-19 03:54 | User Profile
MadScienceType,
You might take look at this site. They soft sell armor and hard plates.
[url]http://www.uscav.com[/url]
You might look at this site. They sell TITANIUM SHEET/PLATE and well cut it for you too. Have it cut to fit the vest pockets and you have the hard plate. You could also do steel but the TITANIUM is not as heavy.
[url]http://www.onlinemetals.com/[/url]
I still agree with what you said before the blunt trauma might well kill or do a lot of damage and likely put you out of action.
2005-02-19 05:49 | User Profile
[QUOTE=MadScienceType]Does that site whose ballistic table you displayed sell to "civilians" or do they only purvey to the King's Men?[/QUOTE] I'm not sure, but I suspect it's only to the King's Men. I didn't see any ordering info on their site -- just contact info, which is a sign that they deal only with governments and security firms as a contractor. Also, the front page of the body armor section of their site has the trite slogan, "Protecting the Lives of Those Who Protect Us" (pardon me while I puke).
For places that sell to "the rest of us," Faust's link to USCav is one possibility. Other possibilities include:
[url]http://www.bulletproofme.com/index.shtml[/url] --- I've never bought from them myself, but they have no qualms about selling to "civilians."
[url]http://www.botac.com/[/url] --- I'm pretty sure they're Jewish-owned, but before I found that out I bought some stuff from them, including an NIJ Class IIIA helmet made by RBR (a company that doesn't sell to "non-approved buyers"). I've been very satisfied with the stuff I've gotten from them so far -- it all appears new and undamaged, the prices are reasonable, etc. If you don't mind buying from Jews -- something it's tough to avoid, anyway -- this is a good place to go. Hey, it's for a higher cause, right? :)
2005-02-19 06:15 | User Profile
[QUOTE=Faust]You might look at this site. They sell TITANIUM SHEET/PLATE and well cut it for you too. Have it cut to fit the vest pockets and you have the hard plate. You could also do steel but the TITANIUM is not as heavy.
[url]http://www.onlinemetals.com/[/url] [/QUOTE] That's good stuff, Faust. It's always good to have the know-how and the resources to "roll your own." Of course it goes without saying that one should thoroughly test out another plate of the same exact type before relying on one of those, since there are many different Ti alloys and some might be too brittle for armor use unless they're really thick and heavy. Another caveat is that a commercial armor plate insert is generally curved to allow it to fit your torso better. Still, it's obviously far better to have a flat plate than none at all.
Incidentally, I wonder if ceramics such as Al2O3 can also be bought in plate form. I imagine they can. The thing to be concerned about there is that the commercial versions of ceramic armor materials are almost certainly inspected for flaws, and that's probably not the case for ceramics sold as building materials or whatever. Once again, testing with live ammo on a plate equivalent to the one you want to use is paramount.
2005-02-19 20:08 | User Profile
Angler
This site has more metal and sells ceramic materials, but I do not know if they would be good for armor. They also have Bullet Resistant Fiberglass Sheets and lots of other stuff.
[url]http://www.mcmaster.com/[/url]
Also you could always try making your own plates Fiberglass and/or kevlar and epoxy. See this site.
[url]http://www.aircraftspruce.com/[/url]
More armor:
[url]http://www.armortex.com/products.html[/url]
2005-02-20 03:39 | User Profile
Angler,
Mcmaster and Onlinemetals have prices on thier site and ready to sell the stuff. Onlinemetals also has CLEAR POLYCARBONATE SHEET which might also be useful.
Mcmaster: Level 4 Fiberglass plate 12"x12" $160.00 Each
2005-02-20 03:48 | User Profile
Isn't the time of knigts in shiny armor, metaphorically speaking, over?