Carbine Handguard Compatibility

[jacotsmith]

Hi all,

I'm sure this has been discussed before but I couldn't find an existing thread when I searched around. I am having compatibility issues with my Chinese-made AR and Israeli manufactured parts. Given their politics who'd have thought they weren't on the same page spec wise?

I have a Norinco 10.5" and I picked up a couple of bolt-on rail sections for the hand guard off ebay. I chose to go with FAB Defense UPR 16/4 rails as they compensate for the angle of the standard fatty hand guard.

Anyway, much to my dismay the retaining screws on the rail don't line up with the vent holes on the hand guard. The distance between the leading edge of the forward screw and the trailing edge of the rear screw is about 121mm, whereas the distance between the leading and trailing edges of the front and rear vent holes is about 116mm. In summary, the rail section is too long. See photo:



I wrote FAB asking what handguards were compatible and they replied with:

All of our AR15 accessories are designed with the classic AR15 Colt dimensions. We have not had an opportunity to review all of the variants out there. If the variant has the identical dimensions of the Colt, then there should be no problem.

I also contacted the vendor on ebay and they directed me to an IMI handguard they carry which they said would work even though it looked identical to my Norc. I tried to buy it off ebay but it was classified as something that wouldn't ship to Canada so I contacted them again and they suggested buying it through their website but their website wouldn't ship this item to Canada either. So I found another Israeli vendor on ebay with the identical product who does ship handguards to Canada so I bought it through them. It arrived the other day and lo and behold its holes have the same spacing as my Norc, (although it is not as "fat" as the Norc - the Norc must be super-fat). So now I have two rails and an extra handguard from two different vendors that won't fit together. Hooray for me.

Now I know some of you will say "just get a quad rail" or "go with a Magpul" but aside from a quad rail being picatinny-overkill and the fact that Magpul handguards look like Darth Vader's cod piece, I just prefer the look and feel of the classic hand guard.

Anyway, can somebody out there with a carbine length Colt tell me what their measurements are? Has anyone else encountered this issue and found a solution?

I realize I can modify the rails to make them fit in a pinch but would prefer to have the proper components if possible.

Thanks for looking!

 

[Blastattack]

My hand-guard has 7 vent holes on .700 centers, and the center of the first hole to the center of the last hole is 4.2". They are on an all Colt upper receiver, but I cannot say if they are Colt manufactured handguards.

 

[Bigfoot 870]

Could you buy a length of rail stock and drill & tap it, to match, yourself? Spacers, to keep the screws "snug" in the handguard's vent holes, could be made, if you can't find anything off of the shelf, that is suitable. Good luck

 

[jacotsmith]

Thanks for your replies.

To Blastattack, both my handguards are the same dimensions as yours. In fact, every fatty handguard I've ever seen are the same dimensions. But I have been lead to believe Colts (and select other brands) are different. But everything I can find basically looks like this:



Same spacing, same relative distance between the vent holes and grip ridges, etc.

To Bigfoot, I could modify these rails slightly and they will fit. I just would rather not have to screw around with a dremmel. I'm more pursuing this out of principal as I was told that they would fit and now I'm on some kind of OCD quest to prove to myself that's true.

Sigh... I might have to go with Darth Vader's jock strap after all!

Thanks again.