Another M4 Handguard Thread ... OMG

[krystofer66]

Ok i am sure no one wants to read another handguard thread but i have read several and keep getting different answers. So long story short, I have a Colt/Umarex M4 carbine 22 lr. It has the polymer handguard. I am wanting to know if i can put regular mil spec AR free float handguards on these or do i need to go with the air soft kind. If so will i need to change out barrel nuts or anything else. A little clarification would be nice.  i plan on looking for a mid length hand guard in aluminum for around 50$ and i would prefer top rail only types if anyone has a lead on one.

[techmike]

Have to admit, I was confused my own self.

* If you have a Colt M4 .22 that has a Delta Ring, you can put any 2-piece mil-spec hand guard on your rifle that is the correct 

  length.

* If you want to replace the existing free-float hand guard on the Ops model, you will have to  change the OEM barrel nut

  with a standard AR15 barrel nut.       

* I had an airsoft hand guard on my Ops model that came with it's own barrel nut - that was because that specific hand guard,

  a Troy TRX, uses a different nut - because the external part of the nut is different.

* The thread size of the Colt .22 M4 is 1-3/16"-16 - same as an AR15.

Attached pics, nut on the right is the Colt OEM, one on the left is a standard AR15 nut. Also a pic showing the Colt with the nut removed.

Hope this helps!

TM

Edited to add, there is an 11" free float rail available in the For Sale thread!

[krystofer66]

I will check out the for sale thread. I was wanting to go longer. So in theory i can take off the front sights fill the holes and replace with standard AR-15 furniture?

[techmike]

Yep, remove the front sights, I used JB Quick Weld to fill the nasty holes in my barrel shroud, and get a standard barrel nut, or whatever your hand guard requires. Edited to add - an AR armorer's tool, or barrel nut wrench to tighten the new nut.