I have a Colt LE6920-OEM2 that's been sitting in the back of my safe for a number of years that I'd finally like to complete. It looks like this:



My only other AR-15 is a mostly stock LE6920. On that one I replaced the handguards with a Magpul MOE (not a fan, will probably change in future) and put on an Aimpoint Pro red dot and flip out Buris 3x magnifier (which works great for hog hunting).

For this build I'd like to have a more streamlined setup, perhaps for practical shooting carbine matches. Not a long range build. I might SBR it at some point in the future and would like to keep that into consideration. I also have a LaRue Tactical MBT-2S Trigger that I never used, but not sure that would be best for carbine matches and am willing to look alternatives.

1) Free-floating rail/handguard.

2) Buttstock

3) Trigger Guard

4) Sights (Backup Iron + Red Dot or 1-? variable)

5) Different trigger?

6) Other attachments? (vertical foregrip, etc?)

I'd love to hear advice from those of you who have built a short-range AR-15. I'm not up to speed on all the new stuff that's out there and am hoping the SigForum brain trust can get me started on my build!

This message has been edited. Last edited by: Wino,

For the trigger, I'd recommend the Geissele SSA. At the very least, I'd change out the stock, heavy, creepy trigger in your rifle to an ALG QMS, or, better yet, an AGL ACT. However, if you're willing to invest the money and you don't mind a two-stage trigger for an AR, the Geissele SSA is the way to go.

For the trigger guard, I recommend the Magpul Enhanced Trigger Guard, Aluminum. I have this on all most of my rifles. I do not care for Magpul's plastic version of this part, which seems flimsy to me. The aluminum version is great, and unlike the plastic version, doesn't have the Magpul logo on the bottom of it.

Also, I recommend the Magpul MOE+ Grip, which differs from the hard plastic MOE grip by having a rubber overmolding. This is more comfortable and more secure than the standard MOE grip.

The standard AR-15 grip is too small for me.

Get a good sling. I recommend the excellent Vickers VCAS, but, damn they have gotten expensive. They have doubled in price in just a few years. Still, if you can afford it, you can't go wrong. Superb customer service from Blue Force Gear.

You already have a low profile gas block, so I'd recommend going with a ~15" free float MLOK handguard, to be able to get your support hand out as far as possible. There are a number of excellent free float rails that are compatible with your existing USGI barrel nut, and won't require you to change that out like many of the other flavors of FF handguards.

For example, the Fortis REV series is lightweight and good quality, and mounts directly to your USGI nut. This one comes in at 15.3" which is just about perfect for your 16" barrel: https://fortismfg.com/reviifre...trailsystem-15.3mlok
(Note: You may be able to find it even cheaper at another retailer, compared to direct from the manufacturer.)


For buttstocks, that mainly comes down to personal preference. Just about any buttstock will work. It just depends on what features you want, and what price range you're willing to live with.

Personally, I really like the MFT Battlelink Minimalist buttstocks. Everything I want, with no unnecessary weight or bulk.
https://missionfirsttactical.com/BMSMIL


For BUIS, I'm a huge fan of the Troy sights. They're pricey, but can be found on sale regularly. For example, PA just had them for $110: https://sigforum.com/eve/forum...0601935/m/3310036805

But realistically, if they're just going to be true backups to a quality optic, a cheap set of polymer MBUS sights is all you need.

quote:

Originally posted by parabellum:
Also, I recommend the Magpul MOE+ Grip, which differs from the hard plastic MOE grip by having a rubber overmolding. This is more comfortable and more secure than the standard MOE grip.

Also check out the Magpul K2 and K2+. (The K2+ has the same overmolded grip as the MOE+, while the K2 is textured hard plastic like the non-+ MOE grip.) These K2 grips have a more vertical angle, which some shooters - myself included - find to work better for them, especially if you're going to be using a more modern squared-to-the-target stance, or when moving and shooting. The traditional AR grip angle was designed for use with the older rifle competition shooting stance, with your support side pointed towards the target.

https://magpul.com/moe-k2-plus-grip-ar15-m4.html

In between the SSA and ACT triggers in terms of price is the G2S. It's an SSA without all the individual testing done and batched tested instead. I picked up two last year on their Halloween sale for $90 apiece. They are excellent triggers. That LaRue trigger you have is LaRue's answer to the SSA, and Geissele responded with the G2S, for whatever all that is worth to you.

As for stocks, pick your flavor of Magpul. I have a MOE SL-K I like, and a CTR is a pretty solid choice for a direct M4 replacement. I have switched to B5 Bravo stocks, though. I like those even better, but they are a little bit heavier if weight is your concern.

I will differ with Para about the overmolded grip. I bought a couple when they first came out, and the rubber has degraded and gone tacky. I know they're cheap enough to just buy more, but I wound up going back to the hard plastic grips as a result. It's just something I don't have to worry about. I really like the K2XL. It's got the same angle as the K2+, but I have big hands and these fill them better. I feel like I have better control over the weapon. I'd say get yourself to a gun shop where they'll pull these out of the box for you to try and just see what you like. Just about everyone has at least a small selection of Magpul stuff to pick from.

As for the Magpul polymer trigger guards, I've yet to break one and don't find them flimsy, but I wouldn't say they're stronger than the aluminum and I've used those as well.

If it were me, I'd skip handguards and go with a rail. There's a lot of choices out there, but my last two were Geissele Mk16's. If was going to build another up anytime soon, I'd use their Mk4. Rogue's suggestion for the Fortis REV is solid, though. I hear good things about them.

If you're going to do a dot and a magnifier, consider one of these instead of a flip-to-side.
https://www.unitytactical.com/product/fast-ftc-30mm/

Note that the optic height 2.26" to the centerline, and this is taller than lower 1/3rd and a lot taller than absolute cowitness, so that's a consideration. I've been using a 1.92" and now a 2.26" height and it was really weird at first, but for a carbine meant to be used at closer ranges, I now see no reason not to do this. Guys talk about "muh height over bore," but if you're shooting at closer ranges, you should be holding for mechanical offset anyways.

quote:

Originally posted by P220 Smudge:
If it were me, I'd skip handguards and go with a rail.

There's zero need to go with the added weight, bulk, and cheese grateriness of a railed handguard in 2024. MLOK handguards have been the new standard for years, and allow for plenty of accessory customization while remaining lightweight. Many handguard manufacturers don't even offer railed handguards any more.

The Centurion C4 rail in either picatinny or mlok variations will drop right on to that configuration with the GI barrel nut to give you a freefloat rail. I like them very much.

https://centurionarms.com/c4-m-lok-rail-12in/

Good photos of the mlok rail installed on an upper with some different angled shots here; you can see how much thinner the mlok version is by the contour needed to accomodate the QD sockets that are flush to the quad rail profile
https://www.tntesales.com/14-5...urion-c4-mlok-upper/

If you choose to use the factory barrel nut, you are kind of limited. Troy MLoks work pretty good as does Centurion for use on the factory barrel nut but the cost is higher. KAC makes one but be prepared to pay out the nose for one. I am not familiar with other brands but I am sure there are a some more.

If you choose to swap out the factory barrel nut you are open to more choices. If you do decide to change the barrel nut, I would recommend having/getting a decent set of tools/blocks to do this the right way. The extra blocks/tools aren't that expensive and you will use them again.

Also, decide on what you really want the rail to accomplish. I have a YHM quad rail on one of mine and it makes the gun heavier/bulkier. I also have an Aero Precision Quantum upper/rail,Mlok, which is much thinner and lighter in weight and will do the same thing my quad rail will do.

quote:

Originally posted by RogueJSK:
There's zero need to go with the added weight, bulk, and cheese grateriness of a railed handguard in 2024. MLOK handguards have been the new standard for years, and allow for plenty of accessory customization while remaining lightweight. Many handguard manufacturers don't even offer railed handguards any more.

A couple things. Being that it's 2024, you'll note I didn't say "quad rail," which is the term we use now for what you describe precisely because it isn't the standard use of that term anymore. Geissele refers to their MLOK handguards as rails, presumably because they, and many others, have a continuous top rail section. I could get super specific and say "free float MLOK handguard with a top rail," but you're the first person I've encountered who defaulted to the 2005 definition of "rail." I have a PRI free float handguard with MLOK slots and has no top rail, and I call it a free float handguard, but I find it has limited utility compared to a rail.

One of these was the first AR I purchased as it gave me the ability to customize some things from the start.

I went with the Fortis rail as RogueJSK mentioned, though I think mine is 13.5". Installation was a snap and it's rock solid. I also did their ambi safety setup over the Radian Talon.

I also prefer the Magpul aluminum enhanced trigger guard like Para recommended and did that on this rifle as well.

For grip, stock and a foregrip I went with BCM.

Mine currently has an Aimpoint Pro with the Magpul pro offset sights for backup. I could add a magnifier if need be.

I have not done anything with the stock trigger setup, at least not yet so I'll defer to some of the other suggestions made so far.

-Geissele mk16 13”
-Bravo company pistol grip
-Magpul moe SL stock
-KAC, Geissele, or Magpul trigger guard
-Arisaka mlok QD sling swivel mount
-Geissele SSA trigger
-Nightforce nx8 1-8 capped with fcdmx reticle in a NF Ultramount
-Arisaka 18650 light body, Malkoff E2XTL head, Arisaka push button tail cap, Arisaka mlok offset mount

Thanks for all the great suggestions!

I compiled a list of what everyone has mentioned so far and will add to this up until I start making purchases and will update with pics once I put it all together. I'm just starting but plan to buy everything sometime in July so keep those recommendations coming.

AR-15 build

1) Free-floating rail/handguard.

Fortis REV II Free Float Rail System - MLOK
Geissele Super Modular Rail MK16 M-LOK
Geissele Super Modular Rail MK4 M-LOK
Centurion Arms C4 M-LOK Rail
Aero Precision Quantum upper/rail,Mlok

2) Buttstock

MFT Battlelink Minimalist Milspec Stock
Magpul MOE SL Carbine Stock
Magpul MOE SL-K Carbine Stock
Magpul CTR Carbine Stock
B5 Bravo Stock

3) Trigger Guard

Magpul Enhanced Trigger Guard, Aluminum
KAC Combat Trigger Guard
Geissele Trigger Guard

4) Sights (Backup Iron + Red Dot or 1-? variable)

Troy Industries M4 Style Folding Battle Sight Set
NX8 – 1-8x24mm F1 capped with FCDMX reticle in a Nightforce Ultramount

5) Different trigger?

Geissele SSA

6) Other attachments? (vertical foregrip, etc?)

Magpul MOE+ Grip
Magpul MOE-K2+ Grip
Magpul MOE K2-XL Grip
BCM Grip
Vickers VCAS Sling
Arisaka QD Mount M-Lok
tools/blocks to swap out the factory barrel nut
Arisaka 18650 Series Light Body, Malkoff E2XTL head, Arisaka push button tail cap, Arisaka mlok offset mount

I think that's the best way to buy a rifle.
Just flesh it out the way that you want and be done.
With all of the choices these days half the fun is browsing.

Midwest Industries makes nice handguards.
I am swapping mine out though for a Cross Machine 13" Arca rail handguard.
I have a 15" IWI one on another made by them and like it a lot.
No need for an additional rail on the bottom and has Mlok slots in the 1,11,3,9 and 6 o clock positions.
The wider bottom sits really well in a bag or such.
https://www.cmttac.com/index.p...5_108&product_id=244

The Magpul SL stock is kinda hard to beat, has QD sockets and doesn't flop around on the buffer tube.

Red dot or LPVO is user preference.
I like LPVO's better and am grinding for an NX8 1-8 with NF mount, pretty much everything I'm looking for in a scope of that type.

I bought one rifle with a two stage trigger in it and a few mil-spec triggers went in the parts drawer soon after.
Centurion Arms has Schmid two stage triggers for about $90 that I used in mine.
Several other vendors sell them as well.

My lowers are all pretty much the same, just either A5 or Rifle action.
K2 XL grip
Radian safety selector.
Magpul or BCM trigger guard.
Two stage trigger
Geissele maritime bolt catch
I use the Radian charging handle in almost everything as well.

I think ARs are a journey. I’ve bounced through many different changes based upon looks and later based upon performance.

My favorite additions include Geissele SSA-E, Radian ambi selector, Magpul trigger guard (like it just a little more than the BCM), BCM stock and pistol grip, and a rail of some sort. I used to say 15 inch rail only, but if I don’t need the extra length for PEQs and the like, I go with a 13.5 rail for a little weight savings.

I like the Blue Force padded sling the best. As to optics, pick something you like. Aimpoint, EoTech, ACOG, etc

I don’t know your experience with this rifle. If you have limited experience I would recommend sticking with a GI style trigger for the first few thousand rounds. The ALG ACT is very smooth and keeps the characteristics of a regular GI style trigger.

I have tens of thousands of rounds down range on this platform and own all the aftermarket triggers mentioned in this thread and have them installed in some of my rifles. My go to self defense trigger on all my defensive use carbines? An ALG ACT (or the BCM or PSA equivalent). A good GI trigger is safe and repeatable and just feels right to me for defensive use.

On a scoped target rifle I’ll use a lighter single or maybe dual stage trigger.

I disagree about keeping a stock trigger. The Geissele SSA is a duty trigger and is the semiautomatic analog of the SSF trigger in use by SOF. It’s not overly light and is very well proven in duty/combat. It’s one of the best upgrades you can add. If money is tight, keep the stock FCG. If you have the means, you won’t regret an SSA.

I'm with Josh on this one, but I'd go one further: If money is tight and the SSA isn't in the budget, but the G2S is, it's absolutely a worthy upgrade and I wouldn't think twice about suggesting it. Fantastic trigger for the money, especially if you grab one on sale, and they go on sale several times a year. I say that as someone who used to have an ALG ACT trigger in my defensive carbine. It's a good trigger, but the G2S is a much better trigger, and I've heard it said the G2S is like 95-98% of what an SSA is.

Even though I suggested the SSA, bubbatime does have a good point about the single-stage ACT trigger perhaps being preferable for a home defense rifle being used by a novice AR-15 user. Notice that he says sticking with a GI-style trigger "for the first few thousand rounds."

While I dearly love the SSA, I think he may be right that if a shooter has not fired an AR-15 before (or fired one very little), being familiar with a single-stage trigger might be beneficial, before moving to a two-stage trigger with a lighter pull.

If I did not have the SSA trigger in my rifles, the ACT is such a refined GI trigger, I don't think I would be losing much in terms of performance. I have replaced all of my ACTs with SSAs in all but one rifle. I've considered replacing the trigger in that rifle, but the ACT is such a pleasure, I may leave it in this iron-sighted rifle.

One advantage the SSA and SSA-E have that gets overlooked is that these triggers (the hammer portion, actually) have half the locktime of the GI trigger (hammer) using the stock hammer spring. After the trigger pull, the hammer hits the primer twice as fast as the GI. Of course we are talking milliseconds either way, but all else being equal, faster locktime can mean (and probably does mean for most shooters) greater accuracy.


The lone ACT holdout:

The SSA is a combat/duty trigger. I don’t see any reason to get familiar with the crummy milspec single stage, even as a novice. The SSA-E is too light for a duty/defensive rifle in my opinion. I like it in a precision gun. But the SSA was design exactly to the full the role we are discussing. It’s not at all too light, it’s very easy to shoot the rifle with it, and it’s not confusing to shoot a 2-stage. I cannot see the upside to a milspec type single stage other than less cost.

I say all of this having been a total trigger troglodyte until about a decade ago when I got my first Geissele SSA. I very quickly changed my tune.

I agree that the SSA-E is too light for a home defense rifle. I have a single SSA-E and it's in a heavy barrel, scoped rifle intended to be shot primarily from a bipod.

It's true that the SSA was designed for and is in use by US Special Forces, but what we must remember is that none of those guys are novice shooters; far from it.

The SSA can be too light for an inexperienced rifle shooter. Glass breaking at 3 AM, you're awakened out of a sound sleep, your body gives you a good shot of adrenaline, and your fine motor functions are compromised. It's hairy enough slinging lead inside an occupied dwelling as it is. Add to that the possibility of negligent discharges from a rifle with a refined trigger- these are things to consider.

For myself, I have considered these things. I choose the SSA, but it's not for everyone.

quote:

Originally posted by parabellum:
I agree that the SSA-E is too light for a home defense rifle. I have a single SSA-E and it's in a heavy barrel, scoped rifle intended to be shot primarily from a bipod.

It's true that the SSA was designed for and is in use by US Special Forces, but what we must remember is that none of those guys are novice shooters; far from it.

The SSA can be too light for an inexperienced rifle shooter. Glass breaking at 3 AM, you're awakened out of a sound sleep, your body gives you a good shot of adrenaline, and your fine motor functions are compromised. It's hairy enough slinging lead inside an occupied dwelling as it is. Add to that the possibility of negligent discharges from a rifle with a refined trigger- these are things to consider.

For myself, I have considered these things. I choose the SSA, but it's not for everyone.

I have somewhere between 1-2k rounds down range with my current Colt build. I guess I should just finally install the LaRue MBT-2S that I already have sitting in a drawer to see what I think about a two stage trigger, then perhaps upgrade to an SSA down the road.

Appreciate the discussion. Now I'm thinking about a long range build for the next one after this...