Difference between rail size?

[irishfan]

I have been looking at rails for a new AR15 but I have a question that I can't seem to answer. I am wanting to build another carbine but wanted a longer rail but I was wondering if a rifle length quad rail will fit my carbine system? I don't want a 7" rail so I don't know if the longer rails will fit the carbine system. Any help is appreciated.

 

[Colt556]

If I understand correctly you could try a Dissipator upper. It has a 16" bbl but regular full length handgaurds. I have one and really like the feel/ balance,

 

[irishfan]

If I understand correctly you could try a Dissipator upper. It has a 16" bbl but regular full length handgaurds. I have one and really like the feel/ balance,

Thanks for the response....I do want a full length setup but have a carbine rifle.

 

[shooter521]

I am wanting to build another carbine but wanted a longer rail but I was wondering if a rifle length quad rail will fit my carbine system?

A free-float rail system longer than carbine length (7") will require the use of a low-profile gas block that will allow the rail to fit over it. You would then have to use a detachable fixed or flip-up front sight on the rail.

MI 10" rail on a 16" M4 barrel

You could also go with one of the "extended" systems that has a cutout for the front sight base:

DD RISII FSP rail on 14.5" barrel

Non-free float systems that make use of the front handguard retainer obviously won't work in this kind of application.

HTH!

 

[irishfan]

Actually, what you described with the flip up front sight is what I am wanting exactly but I didn't know if there was a difference between a rifle rail and a carbine rail except length?

 

[shooter521]

I didn't know if there was a difference between a rifle rail and a carbine rail except length?

Nope, just length.

 

[jtmarine1911]

Shooter beat me to it, and is right on the money in the advise department! I am currently building an upper Identical to the 10" MI picture Shooter included.