View Full Version : Colt M4 Carbine Rail System

04-19-2011, 12:40 PM
I just purchased a used Colt M4 carbine (non-OPS) and would like to upgrade the forearm grip to a quad RIS. Does anyone know if I have to use the Umarex RIS or can I use any other Mil-Spec RIS for the AR-15 delta ring system? I have my eyes set on the UTG RIS sold at CTD. Any help would be appreciated, thanks!

Here's the RIS I am looking at: http://www.cheaperthandirt.com/ARR238-7.html


04-19-2011, 1:07 PM
Are you sure you are in the right section? Is your M4 rimfire 22lr or centerfire 223?

There are a wide variety of 4 rail hand guards that are really nice. Avoid the UTG or non-branded stuff. It will not hold up to abuse or maintain zero overtime. Which is the point of a 4-rail hand guard. If you go with UTG or Umarex you are just getting it for looks, only everybody will know it is not a decent one just by looking at it. They are basically glorified airsoft parts being passed off as firearms grade.

Good entry-level brands that make drop-in 4-rail handguards...

- YHM. I am not a huge YHM fan, but they are firearms grade and they are affordable.

- Midwest Industries. They just redesigned their drop in 4-rail hand guards and they have lots of improvements. I've been very impressed with this brand.

A little pricier drop-in options...

Troy Industries. I would probably rather go with Midwest Industries because I don't think these particular hand guards are any better than theirs, but Troy is a very well respected brand.

Daniel Defense Omega FF Floating Drop In Rails. These are great for people who want free floating but do not want to remove their delta rings. They are a tad pricey, and you have to ask if free floating is really worth it.

New Surplus Knight's Armament. You can occasionally find people selling genuine KAC 4-rail drop-in hand guards dirt cheap. I personally run KAC. I like the authentic original look.

Why go 4-rail at all?

Back when I first purchased my AR15 (not counting my military days which occured long before the 4-rail handguard existed) 4-rail handguards were all the rage. They were new, and everybody wanted them. Nowdays, people realize that they add a lot of weight to the rifle that is very hard to justify if you do not have a specific need for it.

Magpul MOE handguards are just as popular, weigh considerably less, and still allow for accessories light lights and forend grips via the addition of short modular rails that you place only where needed. Unless you need free floating for an SPR or precision rifle, they don't make as much sense as they used to. These are the "new" four rail handguard. They are more popular these days. I sell 50 of them for every 4-rail handguard I sell. And for good reason.

Of course I am one to talk, both my ARs have 4-rail handguards. One because they are genuine KAC's and I don't want to part with them. One because it is a precision setup. If I did not already own the KAC's, or was starting a new run-n-gun build, I would go with the Magpul MOE handguards instead.