Choosing The Right Rail For Your Gun


So You’re Wanting To Replace That Handguard With A Rail…

One of the first customizations AR owners make with their rifles is to upgrade the handguard.  There are literally hundreds, if not thousands of options available which can make it really hard to pick the ONE that you want.  When you first start looking into a new rail you first need to decide which route you want to go…free float or drop in.  To help make a decision you need to ask yourself a few questions.

What Do You Plan On Attaching To Your Rail?

This doesn’t seem like a big deal, and for most of us weekend warriors it probably isn’t, but your attachments can dictate which rail will work best for you with best performance in mind.  A popular attachment is either an angled foregrip or vertical grip.  Either of those options will work perfectly on a drop in or free float rail.  Now if you plan on attaching something like a Harris bipod or anything else that will be used to prop up the run for long range shooting is when you will want to consider a free float.

Angled Foregrip
Angled Foregrip
Vertical Grip
Vertical Grip

Why should you opt for a free float rail just to use a bipod?  The simple answer is that the bipod is “pushing up” on the barrel which can effect accuracy, it is also said that it can throw of the harmonics of the barrel.  Since a free float rail is attached to your upper receiver, no pressure is place directly on the barrel so your accuracy will be much more “true.”

Ease Of Installation

Another big thing to consider is how comfortable are you disassembling your rifle.  A drop in rail is pretty simple, push down the delta ring and snap it in place.  The free float requires a little more work.  Depending on your current setup and the rail you intend to install, you will probably need to remove your current front sight/gas block, the gas tube, the delta ring, barrel nut (if a proprietary barrel nut is required), and flash hider/compensator.  You will need a few specialized tools, but you are an AR owner, you should have them anyways, right?

If you want a free float with the ease of a drop in, there is always the Daniel Defense Omega Rail.


  1. I’m in the process of swapping out my 10″ Troy quad rail with a 13″ BCM KMR. I’m not going to attach a lot to my rail and the KMR is half the weight of the quad rail despite being 3 inches long.

    I’m adding a Fortis short grip and apart from irons and optics that’s all I want on it for now. Every new thing I add just makes it heavier and heavier until it’s just too much and I have to start over from scratch.

    As far as lightweight rails go though it’s hard to beat the KMR