Roller-delayed firearms are among the most reliable, softest-shooting guns in existence. The most prolific examples are the MP5 sub machinegun and the G3 battle rifle. But one lesser-known roller-delayed rifle is the Heckler & Koch-built HK93.

This select-fire version of the rifle is chambered in 5.56, and feeds from detachable, box-type magazines and represents HK’s attempt to compete with the American M-16. Despite being a very effective, reliable firearm, the HK93 never became as popular as the M-16, or the G3 it originates from. Because of this, surplus magazines and accessories aren’t nearly as common for other, more prolific designs. Thankfully, after some digging, I narrowed down the top five upgrades for the HK93, and civilian variants like the Century Arms C93.

HK Parts.net Railed Handguard

Nine times out of ten, I’m the sort of guy to recommend polymer handguards over railed ones unless the shooter specifically has a need for the rails. Oftentimes, shooters buy railed handguards thinking they’ll mount everything from lasers and lights to foregrips and handstops. Once they install the rail, they realize two important things: most rails are much heavier than the original handguards and they’re usually very uncomfortable to hold.

Photos by Jim Grant

HK Parts Inc. circumvents both these problems with their M-LOK handguards. Since the design uses the M-LOK interface, the handguard doesn’t have razer-sharp Picatinny rails that tear up gloves and shooter’s hands alike. More impressive is the fact that the HK Parts M-LOK handguard actually weights exactly the same as the original polymer one with a heat shield.

That means a shooter gains increased durability, rigidness and modularity. Sounds like a slam dunk, and it is for the most part. The only downside of the handguard is price, the HK Parts M-LOK and KeyMod handguards retail for $369. Thankfully HKParts.net normally sells the handguards for about 50 percent off, at $179.

MFI Optics Rail

One of the most frustrating aspects of running a roller-delayed firearm, is mounting optics. Unlike more modern firearms built or modified to accept optics from the factory, most roller-delayed guns require an adapter. Not dissimilar from mounting optics on an AK rifle. Unlike an AK rifle, the mount isn’t quick detach and requires a little finesse to both not damage the host firearm and to mount in line with the barrel.

In response, MFI developed a rail that’s about as idiot-proof as they come. Most HK rail mounts are claw-pattern where a wedge with a threaded hole sits below the rail connected with a screw. As this screw is turned, it clamps the rail to the top of the rifle’s receiver. Sounds easy enough, but in practice can be very frustrating for two reasons. First, it’s possible to accidently crush the receiver by over tightening, and second the retaining wedges can work themselves loose and fall off.

The MFI rail uses 50 percent more clamps to more evenly distribute the torqueing force of the rail. Also, the clamps are retained to the rail with small roll pins. Lastly, the MFI rail is designed to make over-tightening more difficult while preventing the screws from coming loose.

Beta Company 100-round drum

HK93 magazines are expensive, so if a shooter is going to break the bank stocking up on magazines, they might as well buy the ones that hold the most rounds. For the HK and several other firearms, this means Beta Company.

The dual-drum design of the Beta magazine is as iconic as it is effective. Traditional ammunition drums hang too far below the host’s pistol grip for shooters to use while prone or shooting from a bench. The Beta Company drum stuffs 100-rounds into a magazine that only projects a few inches below the magazine well.

In testing, the Beta drum is an absolute blast to run. It may be a little heavy, and its width can be tricky to get used to initially, but once a shooter is acclimated, it offers unparalleled reserves of ammo. Plus, the way it looks on an HK93 is pretty darn cool.

SilencerCo Saker762 and ASR Flash Hider

SilencerCo is the leading producer of sound suppressors in the United States. They’ve done more to advance private silencer ownership than every other company combined, dramatically increasing the number of suppressors in private hands. The majority of SilencerCo’s product line is geared towards more common firearms like AR-15s, Glocks and SIG Sauers. However, the modular nature of their multi-caliber sound suppressors like the Hybrid and Saker allows them to be mounted on a variety of different firearms.

This is thanks in no smart part to the recent development of the ASR, or Active Spring Retention Mount. Previously, the ASR mounting system was limited to the newest offerings from SilencerCo. Recently, whoever SilencerCo added ASR adaptors for its older designs like the Saker 762. This proved so successful that SilencerCo now ships all compatible sound suppressors with ASR mounting systems.

As an owner of a Saker, I was absolutely thrilled with the announcement of an ASR flash-hider compatible with HK93-pattern firearms. For some odd reason, HK choose a 15x1mm thread pitch for their rifles; one that never caught on with American arms makers.

That means the selection of muzzle devices available for the HK93 platform are few and far between. So when SilencerCo formally announced an ASR-compatible flash hider, I knew it would be a slam dunk. Not only does the three-prong flash hider function more effectively than the factory bird cage flash suppressor, it also acts as a QD mount for my SilencerCo Saker 762 sound suppressor.

The Saker is great for noise reduction, flash suppression and recoil mitigation. One of the rarely discussed benefits of running roller-delayed firearms suppressed is that it also increases reliability. This is because the suppressor increases backpressure, which in turn more positively cycles the action.

The downside?

The increased back pressure also means increased internal carbon buildup in the receiver, so shooters will have to clean their rifle more often.

Zeiss Z-Point reflex sight

Zeiss makes a reflex sight?!

Indeed. They make a really nice reflex sight that the German military utilizes on their MP7 PDW. This same reflex sight sits lower than those designed to cowitness with the iron sights on an AR-15 — which might make it less than ideal for that rifle, but great for the HK93.

This is because the 93’s diopter and notch iron sights have a lower profile than those found on the AR-15 and its derivatives. But the height of this optic isn’t the only reason HK93 owners should consider the Z-Point for their rifle.

The Z-Point has two other amazing features that truly endeared me to the design. The first, is a built-in solar panel that passively powers the unit when exposed to sunlight. This alone makes the optic a stellar choice for preppers and survivalists, who worry about battery availability. For regular shooters, it means not concerning yourself with how much power your batteries have, or if you have spares on you.

The other major feature I really enjoy is the QD mounting system. The Z-Point uses a spring to secure it to a Picatinny rail. While this doesn’t sound impressive, it’s the way Zeiss employs the design that really sets it apart from competitors. To disengage the mount, a shooter simply pushes a button forward, then inward, before pulling the sight free. This is easily accomplished with one hand and requires no tools whatsoever.

Pro-Mag 40-round polymer magazines

Magazine availability and affordability are the two biggest drawbacks of the HK93 platform. Factory magazines often run around $80. While these mags are very high quality, they are prohibitively expensive.

Which was probably the impetus behind the ProMag HK93 polymer magazine. Built from high impact polymer, ProMag manufactures reliability, inexpensive alternatives to factory HK93 magazines.  While some may argue certain varieties of ProMag magazines aren’t the best quality, their HK93 mags are on par with factory examples — at least in terms of functionality and reliability.

Plus, compared to the 40-round aluminum HK magazines, ProMag magazines are much more durable, and about half the cost. They might not win over the HK-purist, but shooters looking for solid spare magazines should pick up a few to keep their 93 fed.

The HK93 is often considered an exotic choice for modern sporting rifle, but it shouldn’t be. It’s a time-tested, reliable platform with a few manual of arms quirks that training can easily overcome. Shooters who love modern sporting rifles, but want to stand out from the pack should take a closer look at one.

And if you want your HK93 to truly reach its potential, pick up a few of these upgrades.