Range Report 7.62x39 penetration of phone books

[rideHPD]

Does anyone have any good data on this? I work in a research lab that is working on armor, and am going to test some samples this weekend, hopefully using phone books to catch any rounds that aren't stopped by the samples. I need to know how deep a 7.62x39 round can penetrate through dry phone book material so I can get a ballpark as to how many I need to collect. As you can imagine in this day in age not many use paper phone book and it isn't easy getting a hold of them. The fewer the better.

And please no conspiracy bullshit, you don't need to know that, you're a survivalist, blah blah blah. If this project works the next generation helmets will be able to stop rifle rounds AND weigh around half what the ECH does.

 

[pawprint2]

how thick are the phone books? What velocity/bullet is the 7.62x39? Different weapons/barrel lengths=different velocity. Different bullet construction, i.e. steel core ammo may just penetrate a touch further than brown bear, when fired at same velocity. ETC.

 

[MontanaMarine]

Maybe some of this info will be useful,

The Box O' Truth #31 - The Books O' Truth - Page 1

 

[rideHPD]

Thanks for the response. You're right though, I need to specify more, I was racing to get my samples done and wasn't thinking about that. Rifle used is a std. 7.62x39 AK, Russian milsurp, so steel core, guess that's going to be right around 2350 FPS. I had seen that test with my Googlefu, but I don't know how much it helps. Guessing it's going to take anywhere from 7-18 inches. If I can narrow down that gap that'd help. I have about 90" of ph

 

[tomcatfan]

I'm sorry but I don't think there is going to be anyone on here that will be able to answer your question with any kind of accuracy. I'm kind of surprised to hear that you’re doing the kind of research your talking about and are using phone books as a back stop. First off a muzzle velocity is irrelevant to your question because what your going to need to know is the velocity, projected mass, and flight profile of the object/objects after it penetrates whatever your shooting at. I guess you could do a worst case scenario assuming your samples don’t absorb any energy or break up the bullet but then you are going to use a lot more phone books than needed.

Why don’t you just use an AR-500 steel back stop or better yet a bunch of earth. Are you assuming that the projectiles will follow a linear path through your sample? Are they expected to fragment upon impact? Depending on the structure your impacting, these make big differences.

 

[40xs]

I know the 7.62x39 is not in the same category as the old M1- 3006, but it would shoot through a dump truck bed and trees 30 inches in diameter. So I would say you got your work cut out for you !

 

[tomcatfan]

Keep in mind that if your armor does stop the bullet, the little steel cores have a tendency to bounce back.

Thats one of the reasons why armor is such a crazy complicated subject. There are hundreds of things to consider. I mean sure, you shoot at enough people and eventually an Ipod will "stop" a round. But does that mean I'm using mp3 players as a life saving tool... not today anyway.

 

[tnichols]

I don't know shit from apple butter, but if it was up to me, this "research" would be performed on a square range outdoors and as a previous poster said, let mother earth stop the whatever chooses to keep going. Just sayin',

 

[xciapup]

What is a phone book?

 

[JWV]

What is a phone book?

They are these thick paper books used for ballistics testing that tend to accumulate on front porches yearly. I have no idea of other intended uses.

 

[tomcatfan]

They are these thick paper books used for ballistics testing that tend to accumulate on front porches yearly. I have no idea of other intended uses.

And what do they have to do with phones again?

 

[Grizzdude]

And what do they have to do with phones again?

The ballistic test material that get delivered to everyone usually have some sort of phone picture on them, beats the heck out of me why?