FightLite MCR – The Blue-Collar Belt-Fed AR-15

Jim Grant shoots, and range reviews the FightLite MCR belt-fed upper for AR15 lowers.

U.S.A. -( I love all bad-ass belt-fed weapons like the FightLite MCR; They’re just so damn cool. Sure, you could argue that a magazine-fed rifle is more practical, lighter, and compact, but if you’ve ever seen the look on Animal Mother’s face in Full Metal Jacket, you know exactly how it feels to wield one.

In fact, my experience with belt-fed weapons is limited to a Russian PKM and an FN M249, and while both were near-religious experiences, I never expected to realistically have one myself unless I hit the lottery. After all, a transferrable M249 (or likely a Minimi)- when you can actually find them – is north of $500,000! This fact and the price of military-issued M249 SAWs are the likely impetus for the FightLite MCR’s development.

Fighlite MCR Magazine
The FightLite MCR can feed from a standard M249 SAW belt or a STANAG magazine. IMG Jim Grant

But the MCR is more than just a budget SAW, so let’s take a closer look and see what makes it so special.

FightLite MCR Upper

The FightLite MCR is a lightweight, closed-bolt, belt-fed, short-stroke piston-driven semi-or-fully-automatic upper receiver for the AR-15. Both the full and semi-auto versions are compatible with any semi-automatic AR lower, but function in only semi-automatic mode unless the shooter has a transferrable full-auto trigger pack or a registered lighting link. (The link only works in the semi-auto-only version that incorporates a bolt carrier cut to Colt SP01 specifications.)

One of the cooler features of the MCR is how it’s not just a modified AR upper, but a purpose-built SAW replacement. This is why both versions can feed from either a standard M249 SAW belt or a STANAG magazine. It’s also why the gun incorporates quick-change barrels that allow shooters to swap them out during extended firing sessions where the gun can overheat while providing suppressive fire.

Fighlite MCR Belt
Using a belt to load the MCR is a breeze. IMG Jim Grant

To replace the barrel, a shooter needs only to clear the action and lock it open by holding the bolt release while charging the action. Then press the barrel release tab just forward of the receiver top rail, and finally pull forward (towards the muzzle) on the barrel swap handle. Installing a replacement barrel is simply the same procedure in reverse.

Installing the MCR

Although my time with belt-fed firearms is somewhat limited, adapting to the MCR was fairly straightforward and became second nature pretty quickly. One thing that was a little unexpected, was the installation process for the FightLite MCR upper. I had originally assumed that like nearly every other AR upper receiver group, the installation consisted of popping out two takedown pins, replacing the upper, and reinstalling said pins. But there’s actually a little more complicated than that.

FightLite MCR Bolt Release
The FightLite MCR ships with a custom Bolt Release to accommodate the side charging handle and feed tray. IMG Jim Grant

To start things off, a shooter should replace their existing AR-15 lower’s recoil buffer and spring with the ones provided by FightLite with the MCR. Doing so is very easy and doesn’t require any tools. The other step is more difficult and requires a shooter to replace their bolt catch with a proprietary extended one.

Fightlite MCR Handguard
The Fightlite MCR features a Picatinny rail handguard covering its short-stroke piston system. IMG Jim Grant

While most AR experts utilize a punch and a piece of cardboard or even cloth to protect the lower receiver while driving the roll pin in, I just took an old furniture nail and ground off the tip – but I also wrapped it in an old piece of holster leather since I ended up installing the catch on a friend’s very expensive transferrable M4 lower.

After that, simply put the MCR on top of the host AR lower, and you’re almost ready to roll!

Loading the FightLite MCR

Anyone who has ever run an M249 SAW can load the MCR in their sleep – the manual of arms is very similar. But for those of you without trigger time behind a belt-fed beast, here’s the quick and dirty version.

To load the FightLite MCR, first push the tray cover release forward toward the muzzle, then flip up the tray cover. Visually check to make sure there are no obvious signs of malfunction or damage, then draw your ammunition belt across the fed tray and align the forwardmost round to the chamber before closing the tray cover.

Fightlite MCR Belt Adaptor
The MCR uses a billet aluminum adaptor to secure the belt box to the magazine well. IMG Jim Grant

This requires a little finesse, but if you’re using a polymer lead that goes on the end of the belt, you can just drop the entire thing across the feed tray and be done with it.

Once the round is aligned and the tray closed, charge the MCR’s action or release the bolt. The gun is now loaded and chambered.

FightLite MCR Performance and Verdict

For the test, I ran the MCR on both a friend’s SBR lower and another friend’s transferrable, select-fire M4 lower. Across some 1,000 rounds of 5.56mm ammunition (800 rounds of 62gr green tip and 200 rounds of 55 gr FMJ), the MCR encountered around five malfunctions without cleaning. All of these issues stemmed from the gun being very hot and only occurred after the first 500 rounds were fired, leading me to believe they were caused by a combination of heat and carbon build-up.

Fightlite MCR muzzle Device
Although the Fightlite MCR ships with an aggressive compensator, underneath the device the barrel is threaded to standard 1/2×28. IMG Jim Grant

Regarding accuracy, the gun could squeeze out two-MOA groups with either barrel using military-grade ammunition. Meaning that if a shooter wanted to run match rounds through a belt fed and burn money faster than Bloomberg shoving unwanted gun control down the American people’s collective throats, they could do so for an increase in accuracy. But personally, I don’t see the point.

FightLite MCR Belt-Fed AR-15
It’s a belt-fed upper for your AR-15. What more needs to be said? IMG Jim Grant

Overall, with an MSRP of around $8,000, the Fightlite MCR is by no means ‘cheap’. Not in price and certainly not in construction or build quality. Rather, it’s a purpose-built LMG or belt-fed semi-auto that does exactly what it set out to do: beat the M249 SAW in terms of both price and overall weight. Sure, it’s not cheap, but it’s incredibly more affordable, coupled with a registered drop-in auto sear when compared to a factory transferable belt-fed machinegun.

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About Jim Grant

Jim is one of the elite editors for, who in addition to his mastery of prose, can wield a camera with expert finesse. He loves anything and everything guns but holds firearms from the Cold War in a special place in his heart.

When he’s not reviewing guns or shooting for fun and competition, Jim can be found hiking and hunting with his wife Kimberly, their son, and their dog Peanut in the South Carolina low country.

Jim Grant

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Yeah, for that money, I will take a 50 BMG Barret.

Knute Knute

Now we’re talking a real DMR! 🙂

Knute Knute

Make that: Now we’re talking about a DMR on steroids!
There. I like that better… 🙂

Joe R.

Smart ammo box attachment using the magwell


The 2 biggest issues with this upper are 1) There is no way to make it run “open bolt” and 2) Requires the bolt catch/release be replaced. The former is not that big of deal since the odds of using this to save your life is about 1 in infinity. The latter, IMO, is a big deal. I’ve heard of people breaking off the ears supporting the bolt catch when installing or removing the roll pin. With the cost of a select fire AR starting around $30k I’m uncomfortable with that idea and view that as a design flaw of… Read more »


I would have been highly concerned about driving out the roll pin on a $25k+ transferable lower using dodgy tools.

I really prefer threaded bolt catch pins — you aren’t going to snap those off and if you are careful you can remove/install them dozens of times with no trouble.


My 1960’s select fire colt did not come with a threaded bolt catch pin 😉 . So even with good tools I’m a bit hesitant. I haven’t ruled out the MCR but it has given me reason to pause and think about it a little more.

Last edited 1 month ago by DIYinSTL

It’s not hard to swap out the bolt pin, I did it to put in a phase 5 one piece bolt release on my registered fa lower.
Just don’t be abusive or rush and one is fine.


Great piece to have and use with the price gouging 5.56/.223 prices.
But I guess if you have $8,000.00 to throw away for just the MCR UPPER, what’s $500 more for 1000 rounds to run through it ?


I can understand someone who has access to a full-auto lower wanting to use this as it’s probably the only way they could get access to a belt-fed firearm.
However FN sells a semi-auto version of the M249 for $9999, so for about $2k more I get something designed for belt-feed vs this thing that looks a little kludged together. It’s funny because I actually saw an M249 at Scheels which is a regional sporting goods chain.


I have one and also a FM-9 Freedom Ordinance 9mm belt fed . I shoot the 9mm way more lol In my group we are big on battlefield multipliers .
NVG’s ,Thermals ,50 bmg , Belt feds .Comms .
I would recommend a 50 bmg bolt action before the MCR but if you have the funds why not .

Joe R.

It’s beautiful. . . [weeps]


It’s another reminder that US liberals could not have been born in a worse place.


It’s an incredibly attractive weapon that’s as pretty as a girl. But besides a Sadie Hawkins dance its dependability factor would be about zero. The fatal flaw is predicated on the fact that the more parts, springs and gizmos involved in an operating system then the more things that can ultimately go wrong. Sidebar that with the grim fact that American semi-auto gunmakers insist on producing weapons with the moving parts designed entirely too tight. Flawed designs stay flawed. Even fanatical maintenance never changes that. So, for a screen production at the Burbank Studios yes. But an AR in the… Read more »

Last edited 1 month ago by Ledesma
Knute Knute

Agreed. The only thing left out is that belt feed is only good in full auto, which is mostly for fire suppression. Such weapons are supposed to be inaccurate, since pinpoint accuracy is impossible while the firearm is bouncing around under recoil anyway. Better to throw the rounds in a pattern, rather than a group, to keep the opponent’s heads down. That is suppressive fire, and it is different from accurate fire. This brings up some rather large problems. One is that quick change barrels are needed to keep the gun from overheating. Or the WW1 solution of water cooling.… Read more »