Wanting to potentially replace the Magpul MOE SL hand guard with a thin narrow aluminum hand guard, maybe freefloat? FIIK, I like the thin unit that came on my Ruger 556 pistol.

Would prefer to keep the A2 front sight. And don't want to chince this thing up.

What the heck do I need?


This is the FN15 I have, carbine length gas.
https://fnamerica.com/products/discontinued-rifles/fn-15-moe-slg/

It came with this hand guard. One reason this FN was in my reach.
https://www.magpul.com/firearms-acc...-guards/moe-sl-hand-guard-carbine-length

Option #1. Google AR15 two part handgaurd and you're on your way. Lot's of different models to choose from and you leave the A2 sight in place.

Option #2 cut off the top of the A2 sight leaving the gas block portion in place, slide on a one piece tube, add flip up front sight.

modifying front sight

Winner.

So, if I find a carbine length A2 hand guard it's just R&R?

Oh, I see, a two piece drop in carbine length...

Here is one manufacturer, there are others. Some mount on a GI barrel nut, some have proprietary barrel nuts.If you don't want to R&R the sight, stick with the GI barrel nut setup.


Midwest Industries 2 piece handgaurds

Option #3 is my preference, and what I've done before:

Remove A2 sight, install whatever free float handguard you like, then re-install A2 sight. The handguard has to be short enough to clear the sight of course, but does not have to be a 2-piece. No need to modify the sight that way.

I've used a number of the cheaper Matrix handguards for stuff like this. IIRC I used a 9" on the last one, and had to trim about 1/4" off the top front of the rail to clear the sight but it looked good when done.

Ok, two piece or cut the sight off so a one piece can slip over the gas block. Thanks guys. LOL

Gotcha. Thanks

I'd go free float and a new clamp on or set screw gas block. I've wanted to go back to A2 sights before and it's hard to do when you cut them up.

My preference is to leave everything as is and go two piece. (I dig my F'n AR)

This is the one I am considering, street price is right. I have Mlok gadgets.

Appreciate the input folks.

Boomer, check out Troy Industries Delta rail.

I've done it all the ways mentioned & they all work, just depends on your end objective & whether you want a real free-floated handguard & whether you want a short one, as you have, or a longer one. I distinctly prefer longer & floated.

So, IMO, & for my tastes, what Yondering suggests is the best answer................but the others all work too.

UTG also makes some more use-able & cheaper drop-in, 2 pc rails as well & those all more or less equal what you have with just a different look.

MM

No, you don't have to do either one. The front sight has to come off to install the new barrel nut anyway, just put it back on after installing the handguard. Pretty simple and no need to modify the sight or use two piece handguards.

Got it....


MM, that's a UTG pictured.... I will keep looking.

As well as take a look at my carbine when I get home so I am not just imagining what I have!

You guys do realize that I will need another AR so I can do more chit with it....

Carbine gas systems leave very little room for a hand guard if you keep the front sight. To me they just don't look right and certainly are less comfortable to shoot/hold. I have a Colt with the same SL hand guards on it and I think it's about the best option going for a carbine gas system if you want to keep your front sight.

I have another Colt with a 13" Troy Alpha rail/tube and I shaved the front sight off it and use the built in flip up front sight.

I have other longer tubes over shaved or low profile gas blocks and I like those guns better but for a KISS gun, give me the SL hand guards and the standard front sight.

I guess with the one pictured there'd be nothing extending out under the sight/gas block like on the SL? Don't know now. Might look for something like NVhntr's suggestion...

If you want to keep that front sight, it's no biggie to knock the pins out of it , pull it off, to install, then re-install. I've done it a few times without any problems. I douse the pins and fsb/barrel juncture with Kroil and let it soak overnight to loosen things up.

Just make sure you pound the pins out on the smaller of the two ends. Most I have are pinned in with the small end on the port/left side, but I got a DSA barrel that was pinned the opposite way.






A couple YHM floaters I installed this way,

Honestly if you want a longer handguard, I would just get rid of the A2 sight and install a longer free float handguard, low profile gas block, and a Magpul front sight to match the rear. A roughly 13" long handguard is a nice size for what you've got; it'll give more room for hand placement and a longer sight radius too.

That's a good opportunity to install an adjustable low profile gas block anyway, and tune your rifle for your ammo.

That's what I would do also. My responses above were based on your questions.
What are your plans for this rifle? If you're going to leave it with open sights I'm not sure you will gain any noticeable accuracy from the FF tube. With a scope at longer yardage
You might see a small improvement. But will that be from the FF handgaurd or the better sight picture?

I have a scoped carbine with an A2 front sight and a Magpul handgaurd like yours that holds around 1-1/2 moa with the right load.

Thanks Shane.

In this image, the 'ring' piece behind the sight, what's that called?

Appreciate everyone's input.

Handgaurd cap

Who'd a thunk! Next I'll ask what the barrel nut is called ! Thanks!

This is what it looks like when you convert an FN-15 to floating handguard and no A2 front sight.

Just run it the way it's set up now--you won't gain anything appreciable over it.

Buy another AR to set up the way you want with a longer free float handguard.

'Boomer,

Handguard cap, as already noted. I'll just add that there is round and triangular handguard caps. Typically, round is used on the carbine length gas system, and triangular on the mid and rifle. But there are a few exceptions.

If you use an aftermarket handguard like that UTG you posted up, or others that are used in conjunction with the handguard cap, make sure it fits your handguard cap shape. Some fit either cap, some don't.

The reason there is two types of handguard cap is because the triangular cap dates back to the M16/ M16A1 that used the triangular handguards. For the longest time, rifle length handguards were/are designed to fit that cap.

My goal is not longer. Other's have suggested that as an approach to consider. I think it does justify another rifle or two though....


Thanks again. I saw references to the triangular thingy, err, hand guard cap. So, having freefloat compatibilty per my barrel nut style and gas block diameter is needed. Or for a two piece, length and cap style.... On another tangent, a longer sight radius would come from an A2 rifle length gas system, or a long freefloat hand guard and rail mounted front sight. Among other options. I'll need more ARs.

Thanks for the pics David.

Boomer,

The Troy Delta Rail is a true drop in, freefloat handguard that requires zero modifications, is extremely durable, and quite stiff for what it is. It is without doubt the best pitch one can do for a “stock” AR/M4 without modifying it.


Zero chance I would use a non free float, and some mentioned above are weak junk.

The Troy unit definitely looks stout. Been looking at it since NV mentioned them.

Appreciate it.

Not true. What you gain with a free float handguard is consistent POI regardless of sling or rest pressure/tension on the forend. People use them for good reason, and it's not just for looks.

Leaning that way. Just a short, stout, narrow, aluminum, freefloat, retaining the A2. Or, who knows.

Appreciate all the help and suggestions, learned a few things too boot! I know it's old hat to ya'll, that's why I asked.

Form,

Thoughts on the Centurion c4 carbine cutout rail? Solid as the Troy?

What I was really thinking is that if he is going to only run open sights as are shown in his picture, the advantages of a free float are going to be unlikely to emerge in any meaningful way. He needs another AR setup with mid/rifle gas, no sight block, longer free float tube, scope, and nicer trigger to really stack the advantages.

LOL That's an awful lot of assumptions. The carbine wears a 1-4 scope, the Magpul flippy sight is long gone, no complaints on the FN trigger.... Might consider just open sights on this. It's not an accuracy rig, you are right there. Cheers now and always.

Laugh now while you can...

For an iron sighted chrome lined carbine, or even a red dot, I haven't seen enough difference but I get the idea. I do have a DD Omega rail for a carbine that I might try a before and after test with. I just honestly don't know if I can get the SL's off without breaking something. They were a pain to install.

It's all in good fun, for now. LOL