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The SCAR 20S, Space Force Sniper

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It’s been more than eight years since U.S. military members began running around the world with the SCAR Mk20 SSR. And now you can get your grubbies on a damn-near 1:1 clone in the form of the FN SCAR 20S. For a long time now, we’ve seen the Mk20 pop up at trade shows with the promise of eventually being able to buy it. As it turned out, a semi-auto M249 hit the market first (not that we’re complaining about that).

While the 7.62N SCAR-H is basically a Lane Bryant version of the 5.56 SCAR-L, the same isn’t the case with the 20S; there’s far more going on than simply a longer barrel and receiver. The longer trunnion, which FN calls the “wheelbase,” makes for a very rigid barrel configuration. Removing the 20S barrel reveals major differences compared to the skinny pencil barrels of the originals.

You can safely think of the barrel attachment method as a precision chassis gun. The heavier contour of the 20S barrel makes it far more rigid than a SCAR-H, and FN proved long ago they could make a cold hammer-forged and hard-chromed gun accurate back when their SPR line was released.

So What’s the Difference?

There are scant few differences between the Mk20 SSR and the civilian FN SCAR 20S. The 20S comes with a three-prong flash hider instead of a SureFire FH762SV-SCAR device, it only ships with one trigger module (the Mk20 SSR came with two: one equipped with an FN trigger and the other with a Geissele), sights aren’t included, and it says “20S” on the side instead of “Mk20.” That’s it.

fn scar 20s disassembled

It’s the similarities rather than the differences that gave us some pause, namely the shared 1/12 twist barrel on the FN SCAR 20S and SCAR-H. After all, the current standard of a semi-auto 7.62N rifle is a 1/10 twist. Your ammunition options are slightly reduced with the 20S compared to some rifles, but 168-grain pills are certainly feasible, and even heavier depending on altitude and weather conditions.

scar barrel

The barrel profile of the 20S is significantly different than any other model.

What you need to remember is that the FN SCAR was envisioned as the next big thing for a mass-issued rifle among NATO country members. The extruded aluminum receiver combined with polymer parts made for a rifle that could be produced in large numbers very, very quickly. And the most common NATO 7.62 rounds are below 150 grains, which a 1/12 twist barrel is more than capable of handling.

Changes and Upgrades to OEM

The SCAR Mk20 and therefore the 20S were developed many years ago, and it shows. One remark was, “This rifle is so pre-2010 I’m shocked it doesn’t come with a BAD Lever.” While we have full confidence the FN SCAR 20S will perform in OEM configuration, we couldn’t help but pick it up and notice some serious downsides in comparison to a modern rifle.

We hardly ever see a SCAR heavy or light in OEM configuration — why should we leave well enough alone in this case? So, of course, we didn’t.


The SCAR CQC is shorter than the 20S receiver.

When the original Mk17/SCAR-H was developed, not only were SR-25 pattern magazines fairly expensive, a large swath of them were unreliable to boot, so it makes sense to us that the big brothers to the SCAR Light used proprietary magazines, based on the FAL. However, this is no longer the case today; the advent of reliable and relatively inexpensive magazines from both Lancer Systems and Magpul changed this calculus. As such, one of our first orders of business was swapping out the OEM grip module with one from Handl Defense. Instead of proprietary magazines, now our 20S feeds from magazines you can grab at any Cabelas or big box outdoors store.

Secondly, we addressed the width of the 20S. Long gone is the heyday of the quad rail, and that’s another place it shows its age. While aftermarket options exist from several companies, there are none so far for the longer 20S. Instead of nabbing something from Vltor, Kinetic Development Group (KDG), or Handl, we simply pulled the side rails off. A quick swap of the front screws, and we were in business. We just pretend the new exposed holes in the side of the receiver are part of a cooling system.

fn scar 20s close up

The Handl Defense lower readily accepts OEM parts, and importantly, SR-25 pattern magazines.

Next up was the stock. The Mk20/20S stock is solid. Adjustments stay in place once set, and overall it’s a good buttstock with one thing we dislike: It doesn’t fold. In fact, our decade old SCAR 16 CQC with the stock folded is shorter than the upper receiver of a 20S by itself.

The last several years have seen an increase in the number of precision guns with folding stocks to give them a much smaller footprint for transport. More recently issued rifles such as the M40A7 and M2010 ESR sport that capability, and we figured this one should too. Sure, you could just slap a regular ol’ SCAR stock on there, but we wanted a folding one with the same feature set. Ultimately, we relied on a bit of a hodgepodge to accomplish this. We used a now out-of-production iron6 i6MK4R SCAR/AR adapter as the base, then added a folding mechanism from LAW Tactical, finishing it with a Luth-AR MBA-4 stock with a cheek riser and quick-disconnect sling points.

Speaking of sling points, we addressed those as well. The stock adapter and assembly provided three options for QD sockets on the rear end of the FN SCAR 20S, but we wanted some on the front as well. A KDG SCAR front ambi assembly was an easy button addition, though we had to mill (grind!) it a bit to clear the larger profile of the 20S barrel.

KDG QD points replace the standard loops.

We don’t mind the reciprocating charging handle of the SCAR, but the size of the handle itself makes it hard to manipulate when using optics in general and magnified optics in particular. Our new choice in charging handle also came from KDG.

And, naturally, we had to have a silencer. As mentioned, the FN SCAR 20S comes with a three-prong flash hider and not the proper SureFire device. We opted to keep it in the SureFire family with a SFMB-762 brake. Instead of the requisite FA762SV-BK SCAR silencer, we rolled with a SOCOM762-MINI2. While some may think it wouldn’t be enough, it’s more than ample to allow you to leave your EarPro at home when paired with the 20-inch barrel.

People who are into military clone rifles will hate this one, but we’re sure that we now have the most modernized FN SCAR 20S currently in circulation today.

fn scar 20s stock folding

No buffer needed here. The LAW Tactical folder helps bring us to 2019.

Oh. We almost forgot: We did our damned best to ensure that no colors matched, as is tradition with FN SCARs.

Outfitting for the Range

A rifle like the FN SCAR 20S deserves a decent variable optic, and an offset mini red-dot sight allows you to take advantage of the semi-auto capability if needed up close. You wouldn’t want to have to fight in close quarters with one, but you absolutely could if needed.

For the optic, we went with a Bushnell Elite Tactical LRTSi 4.5-18×44 on a GDI P-ROM mount. A Burris FastFire II in a Primary Arms mount served the role of the offset MRDS.

Regarding the bipod, we’d probably pop an Atlas PSR bipod on the front, but we had a painted Harris S-BRM bipod on hand that we stole from a SEAL sniper — so it was determined to be the best choice. Gear adrift and all that.

Looking at all of our changes and upgrades, one may come to the conclusion that we dislike this rifle. For the truth of that, follow us to the range.

On the Range

We started off by zeroing and later formally grouping the 20S with Black Hills 168-grain Sierra Tipped MatchKing ammunition. As promised by FN, even our very worst groups were only slightly above 1MOA (from shooter error) and five-shot groups were consistently in the 0.80-inch range. This is more than good enough for our purposes.

The real kicker was the recoil, or lack thereof, when used in conjunction with the SureFire silencer. While it’s not uncommon for a rifle to bounce considerably in recoil, we had no such problems with the 20S. In fact, we were able to easily spot our own shots at distances we weren’t able to do with similar rifles. Once we collected our DOPE and made a hit on a USPSA/IPSC torso steel at just over 1K yards, we immediately followed it up with three rapid trigger pulls before the ring of the steel even reached us at the firing line. The result? Hit-hit-hit. Try that with a bolt gun.

We were in lust with the FN SCAR 20S before this range session, but after that performance we were well in love with it.

Loose Rounds

Military cloner nerds and precision shooters alike will definitely find something to love here. While many will balk at the price, those same people will gasp at the MSRP of other SCAR variants as well. For sure this isn’t a budget gun, which makes sense because there’s nothing budget about it. While there are some detractors out there (most notably a YouTube video of some active Navy SEALs), we didn’t find much to dislike here — and the stuff we didn’t prefer was easy enough to change with off-the-shelf parts. We have little doubt that if the FN SCAR 20S kicks off, we’ll soon see the same aftermarket support that its baby brothers enjoy.

And for those waiting for a 6.5 Creedmore Version: it's finally here.

[Editor's note: This article originally appeared in RECOIL Issue 41]

FN SCAR 20S spec box


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