Review of the Krebs Custom AC-15–a refined AK-47

article top
Lot’s of sight radius and the shortened barrel makes it light and balanced.

When Mikhail Kalashnikov died in 2014, his passing was eulogized many AK enthusiasts. At SHOT (the mother of all firearms industry trade shows) that year you couldn’t go anywhere on the floor of the Sands Convention Center without bumping into the image of General Kalashnikov, his chest brimming with decorations. The fact that he was a Soviet Cold War hero didn’t seem to bother anyone red blooded Amerikanskis attending the show.

Although the AK-47 first entered service in the late 1940s, it wasn’t available to people in this country in any great quantities until the iron curtain fell. Since then, many of us have become true believers. As one would expect, as the AK became popular in this country, Yankee ingenuity started improving on this gun.


A gunsmith on a mission

Enter Marc Krebs, founder of Krebs Custom and the builder of the AC-15.

In the world of AK innovation, it’s no exaggeration to say that Mr. Krebs is one the most influential and respected gunsmiths around. Born in Seattle and raised in San Francisco and Mexico, his parents were, in his words, “Beatnik” artists. He was named after one of the most famous artists of the 20th century, Russian-born, French painter, Marc Chagall.

Krebs 1
Marc Krebs, one of the best AK gunsmiths on the planet.

Mr. Krebs’ artistic pedigree serves him well. His father, a painter, was also an inveterate tinkerer and that gene definitely got passed down to his son—along with a large creativity quotient.

A gunsmith, is by definition part machinist, engineer and artist. Not only must everything operate optimally and dependably but it should also incorporate a quality of industrial design that is both functional and aesthetically pleasing. In the case of a Krebs Custom-designed gun, you get a combination of utility and aesthetics.

At his Wauconda, Illinois shop, Marc and his team craft high-end AKs as well as proprietary handguards, sights, muzzle brakes, safety selectors and other items.

The Krebs Custom AC-15 is a state of the art AK rifle. AC translates as “Adaptive Carbine” and the 15 is the year production and sales began.

Why “Adaptive”?

The rifle has a pinned and welded flash hider to give the customer the option of not being stuck with either a flash hider or a muzzle brake. The AC-15 allows the shooter to change between the 4-Prong flash higher to a birdcage brake via the threads on the muzzle device. Krebs is also working on a muzzle brake that would replace the bird cage if the shooters chooses that option. Krebs wants to provide the consumer the ability to treat the AK (with Krebs work and enhancements) as if it was a standard 16” carbine.

front sight adjust
The front sight is mounted on the gas block which saves weight. It’s easily adjusted for elevation with a screwdriver.

Krebs begins with a standard, 7.62x39mm Saiga rifle which he strips down and rebuilds to very exacting standards. Krebs’ team of smiths do a number of things to improve on the factory rifle. This begins with aligning the gas block, the sights and smoothing out the action by “dehorning” rough edges–both internally and externally. Essentially they hand fit all the moving parts. This includes tuning the fire control group. Parts that are already coated with the factory finish are refinished with his proprietary “Krebs Kote“ which is extremely hard-wearing.

All of these little tweaks result in a very refined product. That’s why you’ll pay a premium for a Krebs gun.

What the AC-15 has in common with most modern tactical AKs is a collapsible buttstock. Krebs uses a six-position Magpul CTR model. No, the stock isn’t “traditional” in the old school Kalashnikov sense but it’s very practical. Unlike the Warsaw pact stocks, this can be adjusted to any size “operator”. It’s affixed to the receiver with a special M4 to AK to adapter designed by Jim Fuller of Rifle Dynamics.

A very refined rifle

My very favorite Krebs innovation are the sights, which in my opinion are superior to anything else you’ll find on an AK. Instead of the standard, short-radius, post-and-notch sights found on typical AKs, Krebs has installed an AR-style peep sight mounted on the dust cover. This provides a great deal more sight radius and puts it much closer to the eyes.

I find it vastly more user friendly than anything else out there in AK land and, infinitely easier to adjust for windage.  (In order to adjust for windage on a traditional AK, you need to use a rather primitive tool on the front sight of an AK). The peep site, because it’s mounted directly on the dust cover, provides the geometry that allows you to co-witness in combo with a red dot optic. This is hard to come by on an AK.

Peep 2
The peep sight is a huge innovation–it’s intuitively easier to use than the stock system.

Traditionalists may not like a peep sight on their AK but I think it’s advantage is that it’s instinctively “understood” by the brain. Centering an object within an aperture, at least for me, is much more intuitive that using a notch. Another plus with the peep sight is that it’s easier to aim with both eyes open compared to the stock sight and makes for quicker target acquisition.

The peep sight (which flips back and forth with apertures for long and short range shooting) mates perfectly with the front sight which is mounted on the gas block. It’s also easily adjustable for elevation with a screwdriver.

Shortened Barrel means better balance

By placing the front sight atop the gas block, more barrel is exposed and, consequently, the barrel can be easily shortened. In fact the barrel on the AC-15 is shortened to 14.25” (from 16”). Combined with the front sight/gas block and a shortened barrel, Krebs can remove up to about a pound from the front end. In practice it’s very significant. Balance is considerably improved with a lighter front end and, you get a 19-inch sight radius.

The AC-15 sports a cantilevered mini rail affixed to the rear sight block. We added an Aimpoint clone, the new Truglo Tru-Tec 20mm red dot, which co-witnessed perfectly with the rifle.

To extend the barrel to a legal 16” Krebs has another new innovation, a pinned (and welded) Krebs 4-prong flash hider with a birdcage over muzzle brake. In other words, the muzzle brake screws onto the base of the flash hider. (It indexes perfectly!) The flash hider/brake is welded to the barrel so cleanly that it caused my FFL to suspect that the device was only pinned to the barrel, which would make it illegal under Hawaii Law.

He was disabused of his suspicions by calling Brian Conrad, at Krebs Custom, who explained that indeed the muzzle was permanently attached to the barrel. When I went to the police station to pick up my permit and have them inspect the firearm, they admired the rifle and courteously sent me on my way home. No problems at all.

Other AC-15 accouterments

Another Krebs innovation worthy of mention is a sort of mini-rail that he has mounted in place of the rear site. Made of 4140 steel hardened to 40 Rockwell, it’s solidly cantilevered over the dust cover. It’s an ideal place to mount your red dot scope. You don’t need a full length rail for this rifle which only adds extra weight. This short rail also eliminates the need for a side rail. (The AC-15 has no side rail).

case and gun
The rifle comes with a case and in my case, a heavy duty Bulgarian magazine.

Initially we did have some problems getting our red dots dialed in to co-witness with the rifle. The geometry on the rail was simply didn’t allow us to easily do this. The rail sat very low–so low that even if we maxed out the elevation on the red dot, it barely peeked over the site post. We called Krebs Custom and they came up with a solution.

Heat up the rail with a torch enough to melt the Loctite on the set screw and the adjustment screw, both of which can be manipulated with Allen head wrenches. I decided to invest a few dollars into a blowtorch from Home Depot and in the course of the afternoon, got the rail to co-witness perfectly. Of course it would have been easier if I didn’t have to do this but it was a small price to pay considering the overall package.

We tried Aimpoint clone red dots including the B-Dot from Hi-Lux,  the MD-FBGII from Primary Arms and the just released Tru-Tec 20 mm from a company called Truglo. From our preliminary testing the Truglo looked to be equal in quality to the Hi-Lux and that’s saying a lot. All of the optics co-witnessed perfectly with the mini-rail system.

The UFM handguard, another Krebs invention, is a proprietary KeyMod system. Comfortable, with good heat shielding qualities, it’s one of the best on the market. By definition KeyMod handguards are super light because all the fat is trimmed. Constructed with 6065 T6 aluminum, at 6.6 oz this rail definitely falls into the minimalist category.

If you need to affix a vertical grip or a light, simply slap your own rail and cinch it down exactly where you want it. (Krebs recommends Bravo Company products). The ergonomics on this handguard are also noteworthy. Unlike a conventional handguard/quad rail, which has all the comfort of a pineapple, the Krebs UFM is sleek and quite comfortable to grip. It’s as if the handguard is an extension of the receiver.

The proprietary Krebs keymod handguard is light, and comfortable to hold.

Another refinement that Krebs is well known for is his proprietary safety selector. It offers an extended shelf on the lever which is ergonomically correct and easy to operate. You can flip the safety with your trigger finger while keeping the shooting hand firmly around the pistol grip. The location and shape of the lever, a distinct curve, allows the finger to instantly return to the trigger in one fell swoop.

You’re not going to be distracted or lose your sight-picture, even when using an optic. It also has a bolt hold-open (aka BHO) slot on the lever. The BHO catch allows the operator to easily keep the bolt open so that the range officer can observe whether there’s a round in the chamber.

The trigger is a tweaked, single-stage Tapco G2 system which is pretty much universal among AKs built in the US. It’s very smooth and by examining it you can tell a lot of effort has gone into polishing the hammer and other parts of the fire control group.

At the time of publication of this story I was told that a future iteration of the AC-15 will feature a Krebs Custom-tuned AKT trigger from ALG (a division of Geissele). I have this trigger on my Saiga and think it’s the best on the market.

We used Wolf ammo for the review. No hiccups at all.


The AC-15 is a keeper. With the shortened barrel, the combined gas block/front sight and the keymod rail, it’s as bare bones as you can get on a tactical 7.62×39 AK.

The extended sight radius and the peep sight are a pleasure to use. Everything fits right and works smoothly. The gun never jammed and the Bulgarian magazine fit very snugly in the mag well.

This is not a sniper rifle but chances are you will not outshoot it. The 14.25” chrome lined barrel still provides plenty of velocity and you’ll be able to hit anything you want if you do your part. The balance is vastly improved over a stock AK and the shortened barrel makes it eminently “pointable”.

Muzzle Brake
The muzzle device is modular. You can easily screw on the compensator right over the flash hider.

We tested the gun, with Wolf Ammo (123 gr. FMJ) and it ran without hiccups.

Price is $2100, which includes a case and a very solid steel magazine. As mentioned above you won’t have to invest in a scope mount because of the mini rail and the UFM hand guard. You don’t even have to adjust the sights because it comes laser bore-sighted out of the box.

Yes, it’s an expensive AK but unless you’re a gunsmith, you’re not going to put a similar gun together, with all the labor and parts, for less. Marc Krebs is an artist and that sort of creativity has a price. They are sold directly from Krebs Custom as well as through Atlantic Firearms, Copper Custom and Circle 10 AK.

A big mahalo to CJ and our other friends at Wolf for help in the ammunition department.

Rob Kay writes about firearms for Hawaii Reporter and is the author of How to Buy an AK-47.

Photos by Rob Kay

Questions?  Comments?  Contact us at




Leave a Reply