how strong is Epoxy FRP

[67hat34c]

I am making a mount for my anchor roller, using epoxy resin and a very heavy glass cloth, bi directional heavy weave with a stitched on chop strand layer. soaked very well with resin and rolled it flat and squeezed out excess, no voids. is approximately 5/16 to 3/8 thick.

I decided to make a sample appros 12"x8", 5 layers of this stuff thick. Thinking of shooting it. For fun, any guesses on what ammo will penetrate this. I will try to hit it with something that is commonly used, not a .50 cal sniper riffle, so give me your input for this very scientific experiment.

 

[Avenger]

Okay, put me in the pool. We're talking close range here right? 50 ft or so, not 100 yds. I'll bet .22 long rifle will go through it if you're close enough.

For scientific purposes, I'm assuming five layers would probably end up being about 1/4 in. if that. Unless I remember incorrectly, I laid up a rudder shelf that ended up at 3/4 in. thick and I think it took more than 30 layers of that stuff. At least it seemed like it at the time.

 

[thoward]

Pistol...9mm and up except for the 45
Rifle....All of them

 

[Paul45c]

I decided to make a sample appros 12"x8", 5 layers of this stuff thick. Thinking of shooting it. For fun, any guesses on what ammo will penetrate this. I will try to hit it with something that is commonly used, not a .50 cal sniper riffle, so give me your input for this very scientific experiment.

Your epoxy is brand new without a brittle teaspoon to be found, so my guess is probably a couple of magnum handgun loads might do the trick. I just saw a display of acrylic at a local plastic shop I go to for windshields and the like, and they showed what four handgun calibers did to it. I honestly forget if it was Lexan (probably), but it was about 3/4" thick. Even the .44 mag didn't penetrate, but it came the closest. Next up was the .357. The .22 and the .45ACP hardly bubbled it. Type of bullet will have as much to do with it as power, though. No hollow points, decent weight, etc.

 

[67hat34c]

As Dirty Harry says, " have seen .38 bounce off a panel van, .357 is ok for penetration but I perfer the .44 Magnum"

Dont think a .22LR will do anything. not sure about the 9mm, it is faster than .45acp. . My brother is a cop so he will ask the ranger manager if it is ok for him to shoot it, will try his .45 acp which is his service weapon, he has a variety of loads.

 

[jim rosenthal]

I am not a gun owner, but I recall reading where Willis Slane once invited an off-duty NYC patrolman to shoot at a section of a Hatteras hull- I think the part that they cut out to make the exhaust pipe holes. A standard .38 round did not go through. I also recall Sonny Hines shooting at the same area in one of his hulls WITH a .357 Magnum round, which also did not go through. My guess is that, somewhat depending on how far you are from it, anything short of a .44 Magnum pistol round will NOT go through. I would imagine that most large rifle rounds WOULD go through (.30-06, .223, for example)

Will you post photos of your results?

 

[MikeP]

I took the post to mean there would be five layers, each layer approximately 3/8 thick for a total of 15/8 or nearly two inches. That's pretty thick for the bullets mentioned. Penetration is tough to figure. For example, tests conducted many years ago showed that a 220 Swift firing a FMJ bullet will penetrate 1/2" of mild steel. A 30'06 w/Armor Piercing bullet won't. One would expect the opposite.

But I'd say for shooting through 2" fiberglass/epoxy that a .223 or larger rifle firing an FMJ bullet would penetrate. I don't think any "normal" pistol would.

Let us know!

 

[Bertramp]

wow .... all you guys are packin' ... and I don't even have a slingshot ..... and I'm the New Yorker ..... so much for growing up in "the hood" !!

 

[Avenger]

Maybe I misunderstood the question, are you talking about five layers of cloth or five panels as Mike described. You need to clarify this for science sake.

 

[Capt K]

Don't worry, Steve, I leave mine at the Ct.border when I enter your fair state!

Maybe I'll see you over Thanksgiving weekend, again.

K

 

[Boss Lady]

1.25" of S2 glass will defeat the 30.06 copper jacket lead core bullet at 2800 feet per second and all lesser threats. Be careful shooting at this with handguns, since they can be deflected back at you. I would not shoot this directly, you should shoot at an angle, and be behind proper cover and use eye protection as well. Be careful!

 

[Walter P]

If you're looking to "bullet proof" parts of your boat, it can be done but naturally within limits. If your concern is "amateur" piracy using common guns in typical 9mm Luger, 38 Spec or 357 Mag or even some light caliber rifle cal such as 5.6 mm (223 Rem) then I recommend the highest grade of Lexan for the windows and Kevlar rather than fibreglas for the laminations with Epoxy.

Larger more powerful calibers will probably penetrate whatever we do on any of our boats since they are not intended as military craft.

Years ago I produced speciality rifles in various calibers mostly for target shooting at very long ranges (100 yards to 1000 yards). While it's about 20 years since I sold my interest in the company and took my "retirement" many advancements in small arms have been made. Back then it was fairly easy to penetrate 1/2" steel plate at 100 yds or so. The trick was to be able to penetrate at greater distances. The bad guys have become very resouceful but I think we are concerned with amateurs with lesser power.

Lexan (polycarbonate) panels were(are) available in various grades. Some were formulated to be scratch resistant others had better puncture resistance. Check out the availability of the grade you need (expensive) and get a few rolls of Kevlar and have at it. Good hunting.

Walt

 

[Boatsb]

Fiberglass aint S^*$ for protection against a bullet. Kevler and carbon fiber is much better as the fiber glass will not dissapate the energy into the fiber and will tear. Kevlar is made for this . Ever see the new brain buckets for our guys in Iraq.

I have a 9mm that would probably bust through 5 layers easy but a 45 moving slower at about twice the mass would crush it leaving a big hole.

Chuliota has a nice range to test it. Call me this weekend. Maybe we can do some redneck engineering.

 

[egaito]

Man, has this thread run amok!

If we just want to kill something, let me take a 10mm shot at it, then a nice 12ga slug to see what the big ball of lead will do.

How thick was that layup?

Actually, it would be fun to see what would penetrate an average hull. If anyone DID try to board my boat, it would be much more fun to send them home with a few holes in their hull (and watch) than to actually have to clean up the mess caused by direct hits.

If they were real mean, a couple of quarts of chum over the side before you send them off would be even more fun.

 

[Boss Lady]

Take a look at these "Fiberglass" panels and what threats they defeat: http://www.bulldogdirect.com/directory_frame.html click on safe room panels on the page. It lists fiberglass panels of various thickness that stop 30.06 and 7.62 rifle rounds. There are lighter materials fiberglass such as kevlar or spectrashield, and these high-tech materials cost 10 times as much too. Fiberglass is about $4.00 per pound, kevlar is about $20 per pound and spectra is $40, Fiberglass is the original spall shield that was used in armor systems going back to the early sixties and is still used today. The army bought several hundred thousand of these fiberglass panels for small arms protection used around troop quarters in Iraq. Fiberglass (FRP) is very effective at stopping conventional bullets, just not the exotics, that have hardened penetrators, this requires a hard strike face of ceramic or armor steel to break up the penetrator first. Lexan is a plastic, and is effective against some handgun and submachinegun rounds. It takes 1" thick Lexan to defeat 9mm at 1400 feet per second, this thickness will also defeat the 44 magnum. A 4' x 8' sheet of 1" Lexan costs about $2,000.

p.s. the kevlar helmets that our troops wear only defeat the 9mm and steel bomb fragments, they weight 3.5 lbs for the regular design and 3.0 lbs for the special ops version. They provide limited ballistic protection and in reality are only just OHSA helmets. The lightest helmet to stop even the AK 47 ball round is over 6 lbs in the prototype version and there are only a few in existence. It uses a ceramic outter shell and another material for the spall liner, since kevlar is inadequate for this application. There has been very little improvement in helmet design since the Army scientists are of the opinion that it can't be done, and even if it can be done, the human neck cannot absorbe the impact. (I guess they don't watch a lot of Monday night football)

 

[MikeP]

Football players don't walk around all day with that helmet on their head and 60-80 pounds on their back. They play for 20 seconds at a time and sit on a bench for about half the game. That's the issue with protective equipment - can you deal with actually using it?

In Vietnam in 1968 we were issued the the flak vest of that era. It would defeat fragmentation and pistol but not a rifle bullet. We wore them for about 3 days then tossed them. They were too heavy, hot, and cumbersome for real field operations. They were fine for "lounging around" at a fire base or on a bunker line. But when slogging through the jungle/mud or mountains, whatever advantage they offered for protection was outweighed (literally) by the energy and effort required to wear it.

Re penetration of a normal boat hull - I'm confident a 22LR from a rifle will penetrate easily. I can't say how thick the side of our 53Hatt is but on our last boat, a 36ft Mainship, the hull side, solid fiberglass like a Hatt, was not more than 3/8" thick. Any rifle larger than a .22 would go through one side of the boat and out the other - heck, a .22 might! It's not like the movies where bullets fail to penetrate and simply make big sparks when they hit car sheet metal, etc. If that happened, Bonnie and Clyde would still be around making a fortune on the lecture circuit.

 

[Paul45c]

Re penetration of a normal boat hull - I'm confident a 22LR from a rifle will penetrate easily.

.22's actually are pretty good penetrators, given their small cross section and solid bullet. I've seen several tests where they penetrate far more easily than a .45ACP. Now, that .45 is delivering a lot more energy, of course, but for pure penetration the .22 is pretty good.

 

[67hat34c]

Test panel is only 3/8 thick, 5 layers of this very heavy glass and epoxy resin.

Will try the .22 first as some believe it to be fast enough, still think the little led slug will splat.

would also have to guess that hanging the plate on the wire v building a frame to hold it or putting it on the dirt will make a difference.

 

[egaito]

.22's actually are pretty good penetrators, given their small cross section and solid bullet. I've seen several tests where they penetrate far more easily than a .45ACP. Now, that .45 is delivering a lot more energy, of course, but for pure penetration the .22 is pretty good.

There's a reason that the weapon of choice for "hit men" has always been the 22LR pistol...... Small, quite, especially with a silencer, penetrates the skull better...

 

[MikeP]

3/8" total? I predict the .22 will go through and hardly notice it was there!

Let us know the outcome with appropriate pics! All concerned Hatt owners want to know!