Feelings about Carbon fiber.

[Sobel]

I ordered a windham weaponry src that has a carbon fiber upper and lower. What are peoples feelings about cf and do you think its a good idea to create an ar-15 from it? Here is a link to the rifle its on page 10. Hopefully when I get it I'll be able to add something to the conversation. Would just like to know your feelings about it.

http://www.windhamweaponry.com/pdf/WW Web Catalog 4-2013.pdf

 

[Jackal]

They work for sporting use (targets/hunting), but they do not stand up to real world use (duty). The weak link is at the barrel attachment and the stock attachment. One good fall/roll/dive/drop and snap!!, broken rifle. SO many pics of them broken online, its hard to choose.:banghead:

http://i2.minus.com/ibV6xy.JPG
http://i191.photobucket.com/albums/z172/sumkrnboy/DSCN0007.jpg
http://i49.tinypic.com/2ccup0g.jpg
http://s33.photobucket.com/user/OR_05Taco/media/KB6.jpg.html

 

[Quentin]

I agree. The cost and weight difference isn't enough to offset the strength of standard 7075T6 alloy receivers. I hope it works out for you but 7075 is a sure thing.

 

[Outlaw Man]

I would be afraid of breakage, as well. That said, I've held a few Christensen Arms rifles of various types/calibers, and I can see how the weight reduction from a typically heavy gun would be appealing. I'm not sure a standard AR-15 is heavy enough to warrant it.

 

[adelbridge]

If I remember correctly the bushmaster version had a proprietary buffer. Not sure about windham version.

 

[taliv]

Only the Bushamster complete rifle. Their stripped upper and lower were pretty much compat with any stock

 

[Iramo94]

They work for sporting use (targets/hunting), but they do not stand up to real world use (duty). The weak link is at the barrel attachment and the stock attachment. One good fall/roll/dive/drop and snap!!, broken rifle. SO many pics of them broken online, its hard to choose.:banghead:

http://i2.minus.com/ibV6xy.JPG
http://i191.photobucket.com/albums/z172/sumkrnboy/DSCN0007.jpg
http://i49.tinypic.com/2ccup0g.jpg
http://s33.photobucket.com/user/OR_05Taco/media/KB6.jpg.html

I see mold marks on a couple of those, which means they are plastic, not carbon fiber. There is a huge difference.

 

[btg3]

One good fall/roll/dive/drop and snap!!, broken rifle.

I had that experience with a Nylon 67... and some things can't be fixed. Even so, materials technology continues to advance with amazing applications and performance. Regardless, designers sometimes get ahead of the curve and marketing won't punt.

 

[btg3]

I see mold marks on a couple of those, which means they are plastic, not carbon fiber. There is a huge difference.

Chopped fiber is typically sprayed or molded.
Are you thinking of woven fiber?
There is a huge difference.

 

[Sheepdog1968]

If the goal is a lightweight AR, Doublestar makes a model called the 3C that weighs on the order of 5.75 lbs unloaded.

 

[justice06rr]

I like carbon fiber in other things, but not in firearms. I would not want to have an AR15 with CF receivers just for weight savings alone.

 

[Sobel]

Good to see lots of responses , so its pretty much unanimous the metal is way better than the cf. I feel kinda crappy now lol, perhaps I could eventually get a metal upper and empty lower and just put the parts from the other rifle into it. I would like to know if anyone has had any good things to say about cf.

 

[mag1911]

Mold lines might indicate resin transfer molded.

Aluminum has "strength" in all directions under load. Dry woven or unidirectional carbon fiber has "strength" only in tension applied parallel to the fibers. Carbon fiber/resin assemblies have only the resin matrix supporting loads other than tension. Meaning that the glue holding the carbon fibers together is the only thing preventing breakage from dropping, twisting, bending, etc.

Some of these forces can be overcome by design in larger structures. AR size structures probably not so much.

 

[maxyedor]

That's absolutely the wrong application for carbon. Who's idea was that?

 

[JPG19]

Good to see lots of responses , so its pretty much unanimous the metal is way better than the cf. I feel kinda crappy now lol, perhaps I could eventually get a metal upper and empty lower and just put the parts from the other rifle into it. I would like to know if anyone has had any good things to say about cf.

Did you really wait until after you ordered your rifle to research it?

 

[backbencher]

Great rifle. The Windham Weaponry folks used to work for Bushmaster before it was sold & moved. One of the scary pics above is of a VULCAN plastic receiver, not Carbon Fiber @ all. Another pic is a KB - aluminum receivers don't always fare well after KBs either.

Don't use it for bayonet practice or butt stroke drill, & you'll be fine.

 

[Quentin]

Windham has a great story but just an average rifle, basically equal to the old Bushmaster. As they say, buy the gun not the story!

 

[Sobel]

Did you really wait until after you ordered your rifle to research it?

lol I didn't realize I had ordered the CF version I thought I got the normal src but its my mistake I'm fine living with it.

 

[Quentin]

lol I didn't realize I had ordered the CF version I thought I got the normal src but its my mistake I'm fine living with it.

Any chance of changing or canceling the order? Might as well get what you really want if any chance. The difference in price shouldn't be that much and if it is, well then buy a PSA.

 

[Sobel]

Any chance of changing or canceling the order? Might as well get what you really want if any chance. The difference in price shouldn't be that much and if it is, well then buy a PSA.

I don't know, I think they take a certain percent of the money or something restocking fee or some jazz. I'm fine with a carbon fiber gun i wont be throwing it out of windows or anything. If it explodes in my face and i survive it should be under warranty.

 

[19-3Ben]

One good fall/roll/dive/drop and snap!!, broken rifle.

I used to be a real diehard cyclist (borderline competitive), and had and still have my CF race-bike, and have seen enough of how the stuff works to give some perspective on it. The above was pretty much the rule of thumb we used as well. If you scuff it to the point where a thread of CF is exposed through the resin, ditch the frame before it kB's on you.
The thing is that with metal bike frames, we always had a little warning before it would fail. It would get wobbly feeling, or sag in one area if it was damaged and lost structural strength. But CF can suffer sudden catastrophic failure if it has lost it's strength due to some damage. This is why I never saw the point in a CF mountain bike, where it is so likely to fall, hit rocks/trees/whatever.

Now, admittedly, that's with a 160 pound rider, pumping and stressing that frame with even more than his body weight (you can use the handlebars to hold you down and allow you to exert more than body weight on the pedals), while dealing with jarring potholes and vibration from the road.. The CF parts on an AR see nowhere near that amount of stress being applied.

It is a great material in many uses. Just take care of it to keep it from getting damaged and i guess you could be fine.

 

[Quentin]

Much the same with tennis racquets when the industry was moving from aluminum frames to carbon fiber/graphite. They were strong, rigid and light, until they shattered. Not nearly as dangerous as a bicycle frame that was supporting you above the pavement but still a shock when when it let go. Aluminum might flex but rarely broke without warning.

 

[silicosys4]

i think there is some confusion in this thread about the differences between true woven carbon fiber, and molded polymer reinforced with carbon fibers. True carbon fiber weave wouldn't work on a traditional firearm receiver, I suspect, because of its inabilities to take precise, minute dimensions. True carbon fiber can be thought of as a lighter version of fiberglass, with sheets or mats of woven fibers that are laid then impregnated with resin, then cured.
Im not a chemist, but as far as I know, the carbon rifles being talked about here are polymer with short fibers of carbon added to give reinforcement.

The Windham rifle seems to be fairly well done for a carbon rifle. I wouldn't personally purchase one, but the version the OP purchased seems to be a decent one.
My only personal experience with a polymer ar15 is limited to my brother in law's vulcan polymer 15, which is absolutely atrocious. That rifle is a great example of how much you can dumb down and economize a platform and still get to to kind of work most of the time.

 

[Iramo94]

Chopped fiber is typically sprayed or molded.
Are you thinking of woven fiber?
There is a huge difference.

Mea culpa.

 

[mag1911]

If they are made of short fibers then you also lose the carbon fiber tensile strength and must rely totally on the resin matrix for strength under loads.