Different, but different: Boberg Arm's XR9-S

Article by Daniel Fan.

A jaded LDD visits Boberg Arms and finds himself genuinely interested in a mouse gun, for the first time in, maybe, forever.


[Image used with permission of Arne Boberg, of Boberg Arms]

What happens when you toss out everything you know about conventional pistol operating systems and start from scratch, attempting to maximize the potential of the 9mm cartridge while minimizing the weapons' overall footprint?

Well, one of the things that could happen is the Boberg Arms XR9-S: a pistol that is so “wrong,” it just might be very, very right.

When I first saw the XR9-S, it was on this forum and honestly, I wasn't impressed. I'm not a fan of mouse guns in general. I appreciate that they exist, but my first reaction to the XR9-S was: “Great, another entry into the pantheon of subcompact, sometimes reliable, usually overpriced, and always undercapacitied pocket pistols.”

I didn't give it a second look until Scott Fahey of Big River Leather invited me to drop by Boberg Arm's factory in White Bear, Minnesota. I don't like arriving for an interview with nothing to say, so I broke out the netbook and started some research on Boberg's offerings. And that's when I noticed something that I hadn't see before. The XR9-S isn't just small, black on the bottom, and silver on top. It's also a bullpup, with the ejection port/chamber behind the trigger, not above or in front of the trigger as with standard tilt-barrel designs. In fact, basically everything about the XR9-S happens way behind the trigger. I actually thought of titling this article “The Bullpup Pistol” but to be fair to Boberg, being a bullpup is just scratching the surface of how unconventional the XR9-S actually is.

The Setting



We started the tour in the parking lot of an unobtrusive brick-walled office park. There isn't even a sign on the outside of the building that hints at anything close to the amount of innovation being produced inside.

Arne Boberg, CEO and designer of the XR-9 series, was the first company employee we met. When you talk to Arne, you can tell that he's passionate about his work. Not just because all of his 401k and most of his home equity is invested in his company, but because he genuinely wants to produce the best product that he can. The XR9-S that you'll see today is actually the 10th iteration of a design that started in 2003 and has seen continuous refinement ever since. Boberg himself is a natural at firearms design, having built his first working, match-triggered, single action, single shot pee shooter at age 14 (no joke on that trigger, it's smooth and light).


Arne Boberg, CEO of Boberg Arms, posses with the Boberg Arms XR9-S, in front of...a non-descript looking parts cabinet.

What it claims

In short: full-sized 9mm ballistic performance in a subcompact frame. Specifically, a semiautomatic pistol that yields a 1300 fps muzzle velocity with 115 grain self defense ammunition from an overall platform length of 5.1 inches. To put this in perspective, you'd get about the same MV from a Glock 17, which features a barrel that is only .52 inches shorter than the entire XR9-S. The Glock 17 comes in at 7.32 inches OAL.

Not compromising on the cartridge in such a small package (by going to a .380, .25, etc) usually means not compromising on the recoil either. The XR9-S has five unique features that help to mitigate pushback:

1. A quarter inch of barrel locking distance means that cartridge discharge pressure is completely gone before the barrel and slide unlock.

2. The barrel rotates after discharge, dissipating some of the energy that would otherwise come back at the user.

3. 1.75” of slide travel, which is quite long for this size of gun, spreads/softens the recoil impulse.

4. The XR9-S's unusual loading mechanism transfers force onto the cartridge case, which then acts as self replenishing buffer.

5. Independently flexing nylon grips flex to reduce felt recoil.

XR9-S shown in comparison to SIG P226. Pistol on bottom is a mockup of the XR9-F (not currently in production)

How it works

My first confirmation that this was going to be a really interesting day was a box of assembled magazines sitting on a ship-out table. I grabbed one from the box and looked closely. No it couldn't be...there wasn't a follower. Then Arne came over and loaded a dummy in the magazine—from the back.


[Image used with permission of Arne Boberg, of Boberg Arms]

Not only do you load the magazine from the back, the gun feeds from the back of the magazine as well. In fact, Arne showed me a prototype magazine where the front half was completely enclosed. During the loading sequence, a pair of tongs grabs the cartridge by the case rim, extracts it from the magazine, and deposits it onto a leaf spring which lifts the round to the barrel. The slide moves into battery behind the barrel, chambering the round.

If the tongs index on the case rims, how does the gun insure proper extraction from the magazine when different overall cartridge lengths come into play? Arne designed the XR9's magazine with an internal lip/shoulder on either side, that indexes against the edge of the case mouth. There's enough headspace in the magazine to accommodate any standard 9mm round.


Indexing lips circled in red.

The OAL of the cartridge can change, as long as the case remains remains within spec, the tongs will still be able to find the case rim and facilitate extraction. Weirdly brilliant, yet stunningly simple, all at the same time.


XR9 operating system, video used by permission.

If you're wondering where the slide stop lever is, there is none. The XR9-S doesn't lock open on the last round so slide manipulation is a must when loading or reloading.

How it's made

The XR9-S frame starts life as a block of solid aluminum that is machined out, bead blasted (actually cubic zirconia blasted), and dark hard coat anodized for a protective, blackened finish that is 1/1000th of an inch thick. That may not sound like much, but Arne claims it's 4x the depth of his nearest competitor.

Amidst the assembly benches and C&C machine inside Boberg Arms was a sight I did not expect. Next to a bench with blueprints on them was a Boberg Arms employee, who, appeared to be whittling on a finished frame (!?!).


“Is he hand radiusing that frame?”

Arne has a degree in rocket science so he knew where I was going: the XR9-S is a semi-custom gun, and the frame does indeed require some hand sculpting before it goes to the bead blasting phase. Eventually Arne would like to add the specs for de-horning and edge-blending into the CAD blueprint so the machine can do it, but for now, he has a formula that works. And when you have an 8-12 month backorder to fill, you don't mess with what works.


Machined & blasted frame, ready for anodizing.

So, for now, man will sit by machine and together, they will craft you an XR9-S frame that will, by necessity, not be identical to any other XR9-S. The slide and other parts will interchange, but your frame will be your own—no two will be exactly identical.


XR9-S slides “in the raw.”

The slide starts out life has a hollow piece of stainless steel. According to Arne, there are five grades of Stainless when it comes to working them: easy to machine, moderately easy to machine, moderate to machine, difficult to machine, and extremely difficult to machine. The upside of moving towards the difficult end of the scale is that you get a quality slide. The downside is that, as a manufacturer, a slide that will take more beating is going to break/wear out more cutters. Boberg slides are made with the highest “difficulty to machine” steel, which isn't a uniform practice within the firearms industry—even for major manufacturers who use stainless steel.

Because of the problems with wearing down cutters, Boberg has had to resort to a particular spec & origin of cutter just to maximize their runs.

Once the pistol is assembled, it's test fired to insure accuracy and reliability before being packed up and shipped out.

How it feels

I've handled a number of pocket pistols and they all seemed rather blah to me. Short, narrow grips, fancy serrations to compensate for overall lack of gripping surface, etc, etc. My normal carry is a Glock 17 cut down to Glock 19 specs, though sometimes I carry a Glock 26 when circumstances require. The XR9-S grip is definitely thinner than the G19, but didn't feel much shorter. Arne explained that he didn't want a pistol that you could barely hold on to, and the XR9-S doesn't feel that way. For me, it wasn't a two-fingered grip, nor did the rear end dig into my hand like some pocket pistols sometimes do.

When Arne explained the semi-independent trampoline grips he designed for the XR9-S, I was a bit skeptical. Two independent grip halves sound great until part of your hand gets jammed between them. But, while I made no special attempt to avoid the heel of the gun while dry firing, I never did get pinched.

On to the trigger pull: The XR9-S is a DAO, like most of its mouse gun competitors. Unlike lesser guns, the trigger was very smooth, in two ways. The pull was an even six pounds, with no creep, slop, wiggle, or grit. The trigger face is also very smooth, in a semi-polished stainless steel fashion. While I was dry firing, I felt like my finger was slipping down the trigger face during the pull--just something to note.

Arne stated that the trigger came in six pounds and seven ½ versions. I didn't ask him why six and six plus 1 ½ but I did ask him if he planned to offer anything lighter. He said that if he went lighter than six, he wouldn't be able to guarantee ignition of some of the harder self-defense primers. While I'm a sucker for lighter pull weights, I have to say, I had no problem keeping the front sight on target due to the remarkable smoothness of the XR9-S's DA pull--and I'm no old time revolver shooter with special powers for smoothly following through on twelve pound plus triggers. It does make one wonder why a little shop in White Bear can make a buttery smooth DA trigger when a big shop in Exeter can't, while both charge the same $$$.

The XR9-S is hammer fired, but even the hammer is an unconventional flap-looking piece that normally recesses into the back of the slide. I will say that, as a Glock shooter, it was very disconcerting to see a squarish, thin piece of metal fall away from the back of the slide during initial stages of the trigger pull (you can see the hammer in the first photo of this article). If that happens on a Glock, something is really wrong. I found myself watching the hammer rather than the front sight for the first few trigger presses.

Speaking of sights, I consider tritium inserts to be an eventual necessity on any serious self-defense pistol. Right now, Boberg Arms doesn't ship or offer tritium sights and the XR9-S's sight dovetails aren't compatible with any other manufacturer's (so there's no shortcut by buying someone else's three-dot setup).

Arne plans to start making his own tritium embedded sights within six months. He's currently trying to pin down a deal with a tritium capsule supplier, rather than going through an established sight manufacturer. This is a step he believes will create a cost savings, which he will then be able to pass on to the customer.

The good news for those who have already received their XR9-S pistols is that the sights are user interchangeable so you're not stuck with anything. Night sights for the XR-9 series will be offered direct from Boberg.

How it shoots

Sadly, Arne's small shop doesn't have a built-in range, nor were there any demo units available on such short notice. I would have loved to T&E the XR9-S, because it's the first pistol, in a long time, that I'm interested in from more than a utility standpoint.

And I really wish I could have brought you guys my reactions, but it didn't happen, so we'll move on.

Challenges for Boberg Arms

Boberg's biggest problem right now can be summed up in one word: size. Current monthly production is about 40 pistols, with the bottleneck being the machining process. As of now, the waiting list is growing 3x faster than pistols are being shipped. Sadly, Boberg Arm's production capabilities aren't a match for the demand they've created.

High demand is a good problem to have, but it's also a problem that has to be managed properly because folks can get tired and take their money elsewhere ('Sup HK?). And with Boberg's asking price of close to 1k, there are a lot of cheaper options on the market.

If you're a customer or potential customer who's asking himself “what else is Boberg doing when they could be filling my order?” the answer is: [besides talking to me] nothing. By way of Illustration: when I asked Arne to pose with his product, I also asked him if he had a Boberg Arms poster or banner to serve as a backdrop. He threw his arms out and kind of shrugged. You can see the end result: Boberg Arms is doing everything they can to make a quality pistol without cutting corners on the product itself. Nothing is being spent on t-shirts, banners, bottle openers, or cute models that can't keep their fingers off the trigger. So while you might wait a long time for your own XR9-S, you'll probably be waiting even longer for a girly catalog featuring Boberg products, and that's how it should be. These guns are coming off a 70 hour/ week production line as fast as Boberg and pump them out.


XR9-S in various states of assembly.

Arne actually told me that he's considering pulling waiting list, so that he can raise his price on the XR9-S in proportion to actual production costs. I know there's groans coming from the peanut gallery, but think about this: right now, you could be waiting up to a year for your XR9-S. If you have your heart set on one, how much more would you pay to get one in half the time? How about four weeks instead of a year? Most people would be willing to pay a little more to have their guns faster. That margin could allow Boberg to increase their production and cut backorder times.

It's conceivable that Boberg Arms might eventually get big enough that their production capacity allows for prices to drop, but we're likely years away from that point.

In light of the current XR9-S pricing, I asked Arne who he considers to be his competition. His answer surprised me: “Everyone” Arne went on to say that he's competing on the basis of features, not price. He knows the XR9-S isn't going to underprice Kahr, Keltec or Taurus. He also knows that claiming to only compete against certain brands at higher price points isn't realistic: the gun market isn't big enough for that kind of compartmentalization. That's why he emphasizes the features of the of the XR9-S, like full-sized muzzle velocity from a subcompact package, instead of a simple dollar figure. The XR9-S is intended to compete favorably across the conventionally separate "full size/compact/subcompact" categories.

Still, it's easy to see how someone could go with a gun that was half to a third of the price of the XR9-S. I've stood behind the counter enough hours to realize that 7/10 customers who walk in a gunstore will finger-bang the most expensive model but walk out with the cheapest one. But, for now, the growing backorder list for the XR9-S seems to be proving Arne Boberg right.

The P-word

These days, you can't flip a nickel in a gunstore without hitting something made out of plastic. And since the Boberg Arms XR9-S comes in at just under a grand, I had to ask Arne about the possibility of an XR9-S “lite” made with a polymer frame, for a lower sticker price.

Arne acknowledged it as a theoretical possibility, but not primarily for the cost savings. Boberg's biggest expense, ingredients wise, are the small parts, not the frame itself. The benefit of polymer would be the introduction of a double-stack magazine. I like this idea, but I acknowledge that a polymer frame would probably also result in the removal of the trampoline grips featured on the current aluminum framed XR9-S.

I'm sure Arne could pull it off, but with the current demand for the existing XR9-S, a polymer version is probably more of an exercise in possibilities, rather than a blueprint.

Final thoughts

A lot of my questions are technical, but sometimes I slip in a few that are probes of character. I asked Arne about government contracts and he said he's got a request for three units from the Department of Homeland Security. Those requests haven't been filled because “consumers come first.” Arne's one of us. Well, except that he's got crazy ideas about how to make a subcompact pistol—crazy ideas that might seriously raise people's expectations of the performance a mini-9mm can deliver. In a genre over-saturated with different-but-still-the-same offerings, the XR9-S is pricey, but its features and no-compromise ballistic performance make it a standout worthy of serious consideration.

[Big thanks to Arne Boberg for the factory tour and follow-up interview, and to Scott Fahey of Big River Leather, for arranging the tour. Full disclosure of compensation: the author of this article received a complimentary, full-sized color business card, from Boberg Arms. And he kept it.]

This message has been edited. Last edited by: LDD,

Oh, cool. Thank you, LDD.

-Daniel

Great review.
Looking forward to hearing some range reports on it.

Don't go spending that 'compensation' in one place, now.

LDD, that is one of the best reviews I've read on any forum. Thanks for taking the time to post this.

I have been following the Boberg design for quite some time now and it's refreshing to see such a unique design. My only problem with this pistol is that the slide does not lock back on an empty magazine. I would never carry a pistol for self-defense that doesn't have this feature. That doesn't mean I won't pick one of these up once they become more available.

quote:

Originally posted by fnforme:
My only problem with this pistol is that the slide does not lock back on an empty magazine. I would never carry a pistol for self-defense that doesn't have this feature. That doesn't mean I won't pick one of these up once they become more available.

Thanks, I appreciate the opportunities being a part of this forum provides, including the access I sometimes get and the chance to provide you guys with relevant information.

I actually talked with Arne about a slide-stop-on-the-last-round feature. He said that the way the XR9-S is designed, it wouldn't lock open on an empty anyways, but could be made to lock open after loading the last round out of the magazine. So it would act as a "low fuel" warning indicator. I didn't see a big advantage to having to physically manipulate the slide just to get the last round out.

He explained the mechanism, but honestly, I was still trying to wrap my mind around a number of things about the XR9-S and that's one i didn't catch, so my bad on that count. Arne is a member here and he can correct me on that, or explain why it is.

We did discuss the (again) theoretical possibility of having a "last round" button indicator pop up just ahead of the rear sight. So, how this would work is, you would be shooting, shooting, and then the last round loads. When that happens a button pops up just in front of the rear sight (slightly interrupting, but not completely obscuring your view of the front sight). This would tell you "prepare to reload because your magazine is empty."

Arne said he might also be able to make the button see-saw in such a way that it worked as a loaded chamber indicator too.

I liked that idea much better than having to rack the slide to get your last round out.

I'm really interested in one of these, but will never see one unless he submits 5 to MA for testing. I hope that happens, but I won't be surprised if it doesn't.

The "submit 5 for testing" bullshit is why there are so few "approved" firearms in MA. It's a deliberate ploy.

I really hope he submits 5.

Great write up, thanks...

Thanks, I hadn't really heard of these before.

That's an outstanding review, LDD.

Nice! Now it will be even harder to wait for my turn on the waiting list to arrive.

Wow - thanks for the great review of our facility, Daniel - I didn't expect this after that jaded look on your face the whole time. ;-)

We don't have the slide lock open on the last shot because you wouldn't be chambering a round when you inserted the magazine - you'd just be clinching the top round with the tongs. This is the one compromise we had to make by creating this reverse-feed mechanism.

This message has been edited. Last edited by: abboberg,

Welcome to the forum, abboberg!

I appreciate your ingenuity, innovation, and desire to produce something better than the 'fair-to-middlin' offerings in sub-compact pistols. You've gone well beyond that to give firearms owners a chance to own something functional, original, and unique. I am impressed to see men in this world who still "make" things other than bold statements, catchy phrases, and excuses. Nicely done.

LDD, great article. Well written and concise from beginning to end.

Tremendous review. Thanks for taking the time. Your appreciation of design and craftsmanship really comes through.

Great review! I wish I had the expendable funds to get on the waiting list for one of these. Very high cool factor!

This is one of the first truly innovative firearms I've seen in a long time. A lot of people will have a problem with the lack of a slide lock, but I think it's a fair trade-off for the increased muzzle velocity you get from the reverse feed mechanism and longer barrel. How many people still carry revolvers? It's not like the cylinder of a revolver pops open after the last round is fired.

The Boberg is interesting, but to me, right now, it's just interesting as an intellectual curiosity.

If/when the following all happen it could get interesting in a real world way:
- the guns actually get into the supply chain/owners' hands in quantity,
- they prove to be reliable and durable,
- parts, magazines, etc become generally available,
- the gun proves to have some actual, rather than theoretical, advantages over guns that are actually available now,
- those demonstrated actual advantages justify the relatively high price( is the Boberg worth a Kahr CM9, $200 worth of training, and $300 worth of ammo?)

This message has been edited. Last edited by: texanbeliever,

quote:

Originally posted by jaaron11:
This is one of the first truly innovative firearms I've seen in a long time.

This reminds me of a thread that Bruce Gray started about solving the short barreled .45 problem. In that thread, I asked about the Mars pistol from the late 1800s that had the similar longer barrel and similar rear feed ammo design. I also pointed to the Boberg but the general view in that thread was that the Mars didn't work very well as a design. Because I have handled neither the Mars nor the Boberg, I was left with texanbeliever's questions about seeing them in practice.

It would be interesting to hear from someone with a Boberg. The Mars was known to be a real bear to shoot with a very unpleasant recoil. Abboberg, how do the Boberg's shoot? Are they a rougher ride than other 9mms on the market? Have you had any feedback on the reliability of your latest design? Your aesthetic is very nice. The Mars looked a bit like a piece of conduit screwed into a splicing box.

Thank you very much for a great review of a gun I didn’t even know existed. If it establishes a track record of being reliable and reasonably rugged, I could definitely see myself having one.

Guns in its class are very seldom pushed to the limits of their life spans and very few of them are used for frequent and regular practice. What’s important to me in such a gun beyond reliability is that it is significantly easier to conceal and that it can be controlled and shot well. The fact that its longer barrel for the size of the pistol produces higher velocities is a definite bonus; most little guns have very short barrels and compromised ballistics. If we must accept that as a condition of carrying a small gun, that’s one thing, but it’s much better if we don’t have to accept it.

Some people are on tight gun and ammunition budgets and must make compromises, but others are willing to pay more for better performance. If cost is the only criteria, we can go pretty low before we get to the point of not being able to find something cheaper. I could buy an inexpensive cap and ball revolver and a lot of ammunition for $950, but that wouldn’t make it a better choice for the purpose that the Boberg was designed for.

quote:

Originally posted by sigfreund:
Some people are on tight gun and ammunition budgets and must make compromises, but others are willing to pay more for better performance. I could buy an inexpensive cap and ball revolver and a lot of ammunition for $950, but that wouldn’t make it a better choice for the purpose that the Boberg was designed for.

You, as always, raise interesting points in your posts. I am interested in your "better performance" observation. Will the Boberg deliver better performance?

It is hard to believe there are any better steel materials or a much better look for a pistol in this size but texanbeliever, for instance, contrasted the Kahr CM9 to the Boberg. I was wondering if you find a deficiency in the existing Kahr design. The Kahr is certainly less attractive to me but does it somehow not function well?

The Boberg barrel is 3.35". The Kahr barrel is 3.0. So, is there a lot of velocity difference in that .35"? I suppose velocity only matters when you just don't quite have enough. Do either of these designs, for instance, handle any sort of +p? If so, I wonder at what cost? The Boberg advertises that it uses 5 design attributes to mitigate recoil but what is the stress envelope for those attributes? Are they easy to exceed? Does the Kahr have a relatively constant recoil impulse with all ammo by contrast? Because Boberg relies on the cartridge itself to mitigate recoil, is there a limiting envelope on the cartridge material or does it necessitate only certain types/brands of cartridges? These are just things that come to mind.

The Boberg is 5.1" in length. The Kahr is 5.42". So, the Boberg is a little shorter in overall length. (Dimensions are from the Kahr and Boberg sites.) The Boberg is 4.2" tall. The Kahr is 4.0. So the Kahr is a little shorter in overall height. Hence, they seem to be about the same size.

The Boberg is 3.5 ounces heavier without counting a magazine. So, the weight may help with recoil if all else is equal. But, it is not clear whether all else is equal. If the Boberg design is more snappy, then any weight difference could be offset by having the recoil impulse seemingly originate behind the grip; who knows without hands-on testing?

I also wonder if there is a sweet ammo for each design. By way of analogy, I absolutely hate .40S&W 165 grain Fiocchi ammo in my P226. Others like that type of brisk recoil. I like the 180 grain in other ammo brands much better. So, as you say, once more Bobergs get to the market, more will probably be known.

There is no doubt to me that the Boberg is a very sharp looking pistol made with very high quality materials . . . but that's just my aesthetic view. Do quality materials necessarily translate into "better" performance? I have read things about how the flexing of "plastic" pistols helps mitigate recoil and some people find certain "plastic" pistols much more shootable. Besides the .35" velocity difference and a better trigger, what Boberg attributes would yield "better performance" in your view? Mind you, I have never shot the Kahr either so I do not know.

You make some good points, Tubetone.

I took the company’s velocity claims at face value without comparing barrel lengths. Having done that now, I am very curious what accounts for them. For example, the Boberg site shows that the gun produces 1245 fps with the Speer 124 grain +P Gold Dot (yes, the gun is rated for +P). In my own somewhat limited testing at a slightly closer distance that load runs 1206 fps from a P229 (3.9" barrel), 1213 fps from a P226 (4.4"), and 1226 fps from a P226 with 4.9" threaded barrel.

Velocities vary from lot to lot and SIG barrels have a reputation for being a little “slow,” but I’m quite surprised to see that a 3.35" Boberg barrel drives the load 20 fps faster than a SIG barrel that’s over 1.5" longer. That’s 46 percent longer and is an even greater percentage if we subtract the length of the chamber.

Barrel designs do affect bullet velocities, so perhaps there’s another factor at work besides barrel length. I’d really be interested in independent confirmation of the velocity claims and especially a technical explanation of the reason(s) why.

If, however, the Boberg drives a 124 grain bullet 30 fps faster than a standard P226, that would be a huge factor in its favor.

Added: I checked the Boberg site again and see that the velocity figures are from a “full-sized” XR9-L, but I can’t find the barrel length of that version. More than a little confusion remains.

Added two: After a Google search I found that the -L version has a 4.2 inch barrel. Now the velocity figures make more sense, but they are still worth noting.