Folding Stock Adapter Comparison Pt. 4

1.2. 3. 4.
5. 6. 7. 8.

1. Doublestar Ace FSA, 2. SB Tactical BTFA, 3. Sylvan Arms FSA 4. MDT Carbine|Carbine FSA,
5. UTG/Leapers FSA, 6. XLR FSA 7. Law Tactical FSA (and clones) 8. Hera Arms

Hera Arms Side Folding Unit

Ordered on November 15th from It shipped on November 18th and I got email notifications of order and shipment. It arrived on November 23rd and I immediately pulled it out to do some testing. Finish is fantastic, fit is perfect save a tiny bit of play in one direction.

It’s extremely nice and super compact. Obviously made to that quintessentially Teutonic standard which borders on the manufacturing equivalent of pedantry. Germans just make things well. It’s in their DNA.

It would have been nice if the design didn’t need a snugging up mechanism like the MDT design but, alas, the Hera unit doesn’t come with a snugging up mechanism which cost it a point. Still, ever the optimist, I applied 1 layer of masking tape on the flat mating surfaces and that brought all the wiggle to zero and the sound of it closing took on the thud of a bank vault. It wouldn’t have been enough wiggle to notice behind the gun. Interesting note, when XLR Industries later licensed the design they added two set screws that you could back out to snug the thing up. I’ll forgive it in my heart but still deduct the point and I’ll end up adding those set screws because they just make sense even if a layer of masking tape does just as well.

So far the Hera Arms unit is the most compact by a good ways.
There’s just nothing else to cut off.

It has a decent ball detent does an ok hold-open job for extremely light butt stocks but if your butt is made of metal, it’s probably not going to hold it open against a shake. It will probably not keep the thing from banging you in the head during a hike with the rifle backpack stowed. Even if it’s not super functional it counts as a two way locking design. (NOTE: I’m using “locking” very loosely during this whole thing for fairness.) Manufacturing quality is very nice. No machining marks, nice anodized finish, no dings. Install is as easy as with the XLR unit and pretty much identical though the Hera uses a much smaller allen key for the chassis interface snug-up which I found to be not confidence inspiring. XLR later improved the design and their version uses a MUCH larger allen key which is confidence inspiring. To install, spin the adapter onto your chassis, clock it, snug the hell out of the 2 locking screws, install butt, clock the butt, snug the castle nut.

Did we mention that it’s super compact too? Upside all other units is visibly the smallest by a good ways. The XLR and MDT units are not a lot bigger but they are a bit bigger. Why does side matter for this? It’s mostly a matter of clearance for your bolt cycling hand. Some of these units I’ve tested (UTG/Leapers, looking your direction) stick out in places that hands will eventually be cycling bolts in. Drag your knuckle at high speed across a folding stock adapter and I bet you’ll howl. So, it matters about size and it matters about where that size is concentrated.

Get your Dark Rey on.

Here’s a little trivia for you: Dark Rey’s light saber actually uses a real Hera Arms SFU as its folding mechanism in whatever Star Something movie has a character named “Dark Rey” whom also uses a thing called a “light saber”. It’s true. I looked it up and there are even pictures of it on the movie prop. Cool huh? You can see in the image below the distinctive locking hasp and overall profile and above you can see the actual unit used on the actual light saber from the movie complete with the Hera sticker. Yeah, Hera doesn’t engrave, the use a small sticker. Classy.

This unit, like most of them being tested is not compatible with any AR-15 where the bolt carrier reciprocates through the buffer tube/upper interface. For a bolt action rifle though it’s awesome. Slim, sleek, well made, tough and relatively inexpensive but with all the features one might want and it installs as easily as a child’s finger goes into his nose.

Where did it fall down? No instructions in the box or generally available to a quick Google search and the small size of allen key used to install it. Honestly if you need instructions though, you should not have tools or guns or hands and any of those will just get you into trouble. The rest of us already assume that you’re mechanically inept enough to destroy the Earth with an extravagant gesture. If a small allen key is a stopper for you, then I’ll assume you don’t own anything electronic that ever needs batteries installed. For everyone else, it’s trivially easy to overlook Hera losing 2 points there on the no instructions thing.

It picked up some point value for the steel locking mechanism, lost some for 6061 aluminum body and balanced out at .75 for construction. It lost another full point for no tuning mechanism for the wiggle (though a strip of masking tape works wonders) and for there being wiggle when the bipod is unloaded. It got full pretty much points otherwise and looks like it’ll probably end up either winning for compactness unless the SB Tactical unit is insanely compact. The total score of 14.75 out of 19 places it in a solid 3rd place so far.

part 1.
part 2.
part 3.
part 4.
Mid-Series Check-in.
part 5.
part 6.
Declaring the Winners

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