What sort of polymer is used to make standard AR15 A2 handguards?

I believe they use Zytel which is a glass reinforced nylon, usually 30% by weight glass fibers.

Can you tell me where I can find some 4mm black rod of this stuff? I've a pair of handguard halves that use thin tongues-and-grooves to attach to one another rather than a more robust post-and-hole approach. I can't seem find any sort of 4mm black nylon rod of any kind in small quantities.

Mcmaster Carr has PC6 which uses Poly Carbonate also nylon 6 which is the generic name for zytel. In black and white respectfully in 1/4 rods.

https://www.mcmaster.com/thermoplastics ... nate-rods/

YOu could also clean up the halves real good and use black epoxy which is available at most auto parts stores.

I'd rather be able to easily remove the handguards if the thought occurs to me.

No just use the epoxy to hold the two halves together......it would take quite a bit of epoxy to stick the handguard to the barrel.

Can you drill holes and put tiny dowels in? Shouldn't matter if the material matches

Is this some vintage hand guard that's not made anymore?



Hard to get them off if they're stuck together

Thread needs more pictures of what we're dealing with

This is one with feeble tongues-and-grooves. I tried to smooth up the areas between the tongues-and-grooves, but this didn't help with the problem of the handguards not gripping each other very well. The tongues project barely 1mm over the surroundings.


This is one with posts-and-holes. The posts are around 5mm high.


Drilling holes and making tiny dowels is what I had in mind when asking for sources for 4mm Zytel rod. Epoxying them together around the barrel isn't good because, as you observed, it would be tough to get them off again. Would there be any heat or structural issues with using aluminum rod as dowels? The main reason I wanted to find Zytel rods would be to obviate those concerns. 4mm aluminum rod is much easier to source.

Try to find yourself some Colt hand guards. Most likely better tolerances.
Just for ID purpose. See how my Colt guards look different from yours.

One way to determine Colt hand guards is. They use this opaque glue on some of the tabs.


It’s stuff like this as to why we need the WAC gun show back.
If you ever get down to Kent I’ll hook you up with a set.

Ok now that you included a photo I am wondering why you can't strap it together and drill holes through where those short post are and tap some threads so you can use hex head bolts or torx bolts that are counter sunk. Even phillips heads would work. I have taps that small in my stuff but you could buy the appropriate tap drill bits and fasteners.

For a cheep way to do it contact cement would work but it would be a bugger to open up to take off.

on the side comment about WAC gun shows there will be one in Elma first.
It will be in July on the weekend of the 10th.
A few of us old timers will have tables.

I don't want to bond the halves together because of the trouble of getting them off later on. What I originally thought to do is drill holes on one side of each half. Then into each of these holes, I'd put a very short rod sharpened in a pencil sharpener. The tip would stick out maybe 1mm. Clamp the halves together and a little divot will appear opposite the holes which indicate exactly where to drill. I'd then drill there and glue in (epoxy or solvent weld) rods to one side of each half. Each post should then fit perfectly into their corresponding hole when the two handguard halves are put together. I suppose now that I can safely use aluminum rod instead of glass-filled nylon rod.

Those are cheap copies made from something like ABS at best. Not glass reinforced "polymer," like Colt or FN would use.
Numrich has some they claim are government surplus, and if they truly are... though they aren't saying which government, or if they were Bushmasters bought by a local government to use as Simunitions guns... they would be the proper material.
Probably only a bit more than you'd pay for the parts, and a lot less time than making inserts.

https://www.gunpartscorp.com/search#que ... 0handguard