Ted Karagias of American Rifle Company (ARC) wowed us last year, with his fresh and innovative complete rifle system and an action, earning the title of Most Innovative Product of SHOT Show 2014. Now his Mausingfield Action has officially made it into production, and is available to the public. It received a lot of attention at SHOT Show 2015.
A few weeks ago, Ted sent me action serial #00001 to test, and I used it to fire hundreds of rounds of Hornady 6.5 Creedmoor Match Ammo. Here is a quick video that highlights some of the features of ARC’s Mausingfield Action, and gives my overall takeaway.
There are many approaches to design, but I believe this quote encapsulates the most well-rounded philosophy:
“The methodology used should be based on choice of the latest and best, and not based on ignorance. It should also be laced liberally with the old and dependable.” – Harlan Mills, IBM Super-Programmer
This feels like Ted’s approach with the Mausingfield Action. He incorporated a liberal dose of time-tested and battle-proven designs that are over 100 years old, like a Mauser 98 extractor and ’03 Springfield ejector. He then integrated more recent design concepts like an integral recoil lug, and compatibility with Savage-style barrels for those do-it-yourselfers. Finally, he added a few completely novel and innovative features like no-lap locking lugs, and a keyed picatinny rail interface.
1) Mauser 98 Extractor
Extractor: Primary job is to remove a case from the chamber.
Paul Mauser was a brilliant and iconic innovator, who lived in Germany in the late 1800’s and early 1900’s. He patented lots of things, including most of the extractors in use today. But his 1898 extractor design was the most robust and reliable, and considered the pinnacle of his designs. This was the only extractor he saw fit for use in his legendary Mauser Model 98 rifle, because it could function in the toughest field conditions.
The Mauser 98 extractor offers a few benefits worth noting:
- It’s massive. This extractor engages more of the case than any other design on the market. This can reduce the chance of a case head failure during a difficult extraction.
- Doesn’t rotate with the bolt. The extractor doesn’t rotate with the bolt. It maintains the same point of contact on the case from the time it strips the round from the magazine until its ejected. This can reduce the chance that the extractor will accidentally disengage the case as you open the bolt.
- Controlled round feeding. Many believe a controlled-round-feed (CRF) is more reliable than the common Remington-style push-feed (PF). CRF means the bolt gains control of a cartridge as it is stripped from the magazine, compared to PF which bumps the cartridge loose from the magazine and pushes it into the chamber. CRF is the standard among dangerous game hunters, because you don’t want a malfunction when an animal is charging you. CRF also reduces the likelihood of accidental double-feeds.
- Robust design. This extractor design is passive, and doesn’t require small springs, pins, and plungers. Other extractors rely on small parts to pivot or slide into engagement, and those parts and grooves must be kept clean to function reliably. The Mauser extractor design is far less sensitive to contaminants. Ted says this mechanical design is able to survive case head separation and over pressure events that would likely destroy the delicate extraction systems used in other actions.
2) ’03 Springfield Ejector
Ejector: Primary job is to throw an extracted case from the action.
Many bolt actions use a plunger in the bolt face as their ejection system. This is a simple design, where the spring powered plunger forces the case to flip out of the port once it’s removed from the chamber.
You can see the Mausingfield doesn’t have a plunger-style ejector, but instead uses a fixed ejector similar to the Model 1903 Springfield. It simply consists of a compact hardened steel blade that freely pivots on a high strength steel pin. As the bolt is moved reward, the ejector pivots into place through a slot in the bolt face and hits the case, causing the case to be thrown from the action.
There are a few benefits to this ejector design:
- Better location. This ejector is located at the rear of the action, well away from the intense chamber explosion. On the other hand, spring-plunger ejectors are located within the chamber-facing end of the bolt, which can be a poor location for such a delicate assembly. Blasts can could drive the ejector backwards with enough force to deform or shear the tiny retaining pin, leaving it permanently retracted within the bolt face. Brass flakes or other contaminants can also obstruct the plunger, because it’s driven by relatively a small spring. If you’re able to move delicate parts away from “ground zero,” maybe you should.
- Control how far it throws your brass. The Springfield ejector allows the shooter to control the amount of force that ejects a case. You can protect the necks of spent cases by slowly retracting the bolt, so they fall right next to the rifle. If the shooter is not concerned with collecting brass, the spent cases can be ejected well clear of the rifle by running the bolt as normal. On actions with plunger style ejectors, you don’t have these options … the cases are always flung with the same amount of force. Plunger ejectors can also deform case necks, because the plunger is trying to throw the case as soon as it leaves the chamber causing the case neck to strike the inside of the receiver.
3) Toroidal No-Lap Locking Lugs
When accurizing a bolt action rifle, it’s necessary to carefully lap the locking lugs so they bear evenly on the lug bearing surfaces. But, the Mausingfield features innovative toroidal (donut shaped) bolt lugs that don’t require lapping.
As a mechanical engineer, this seemed like an obvious design to Ted, but it probably isn’t so obvious to the rest of us. Picture a torus (donut shape) inside a spherical bowl. If you put pressure straight down on the torus, it will find its way to the very center of the bowl (its lowest energy state). The bolt works the same way, with the locking lugs as the torus and the inside of the receiver as the sphere. Every time you close the bolt, it finds its lowest energy state, which is centered and properly seated.
4) Keyed Rail Interface – The Best of Both Worlds
I own actions with integrated picatinny rails and actions with detachable rails, and there are pros and cons to both designs. Before we dive into those, let me first make sure everyone understands why the amount of taper (also referred to as cant) built into a rail is important.
“Here’s the problem: if you mount a scope on a flat rail, it will zero near the center of its range of adjustment, and you’ll only have about 1/2 of the scopes available travel to go up. So if your scope has 60 MOA of available travel and you zero it in the center, then you’re limited to 30 MOA of vertical travel. If you need 31 MOA, you’re screwed. The most common fix to this problem is to make use of an angled or tapered scope rail. A tapered scope rail is taller in the back than in the front, so that when you mount your scope, the muzzle is slightly elevated in relation to the line of sight. This causes the scope to zero closer to the bottom of its range of elevation, which means you have more capacity to go up, meaning you can adjust for more drop at longer ranges.” – Bryan Litz, Modern Adv. in Long-Range Shooting Vol. 1
Here is a diagram I created to help illustrate what we’re talking about here:
Optics engineers have told me a scope’s best optical clarity is found in the center of the tube, because the image can be skewed and distorted at the extreme ends of the adjustment range. So ideally you want to be near the center at the range you plan to shoot most frequently.
Pairing your rifle’s rail and scope has real benefits, so it’s wise to spend a minute thinking about what the ideal amount of rail taper is for your rifle and application. Here are some examples of different amounts of cant you might want for different rifles/applications:
- 0 MOA (i.e. flat): 100 yard benchrest rifle or rifle chambered with smaller cartridge like the 223 Rem
- 20 MOA: A mid-sized cartridge like the 6.5 Creedmoor or 308 Win that you plant to shoot out to 600-1200 yards
- 30 MOA: A magnum rifle you plan to shoot out to 1 mile
- 50 MOA: A large magnum like the 338 Lapua or 416 Barrett you plan to shoot to 2000+ yards
My Stiller Predator action included a detachable rail with 20 MOA of taper, and I swapped that with a 30 MOA rail to give me a little more adjustment for longer shots. I could’ve kept the 20 MOA rail and bought a scope mount with an additional 10 MOA of cant, but it seems like a cleaner solution to stick with flat scope mounts (i.e. 0 MOA). That means the mount is neutral, and you can move it to different rifles when needed … because most people (including me) can’t afford a really high-end scope for every rifle. Fundamentally, it seems like a better solution for each rifle to have the appropriate amount of taper built in for that cartridge and application, without having to be further supplemented by the mount.
But there is a huge downside of the detachable rail … it can slip. I had that problem with my Stiller Predator, and it was more than frustrating. It’s extremely hard to diagnose erratic flyers from a slipping rail. But, sure enough I’d finally get irritated enough to remove the mount and discover the rail screws had come lose or later that the steel screws had eaten into the softer aluminum rail. That experience helped me develop a hatred for detachable scope rails. It’s just very difficult to keep a smooth rail from slipping on a smooth action while under recoil.
Actions with integrated rails don’t move … period. That is exactly why I bought a Surgeon action for my last rifle. I didn’t want to ever worry about that rail slipping on me again. An integrated rail has other benefits, like making the action stiffer. But honestly, I just didn’t want it to move. The downside of the Surgeon integrated rail is it’s only offered with 20 MOA of cant. Hope you like it! While 20 MOA is probably the best general-purpose amount to go with, it isn’t ideal for all scenarios. Even if you could order a different amount of taper, what if you used that action to build a different rifle later and that taper was no longer ideal. When the rail is built into the action, it just isn’t as flexible.
What if you could have the best of both worlds? What if you had the ability to swap out the rail to fine-tune the amount of cant for your rifle and application, AND there was no way the rail was going to slip around? Yep, that’s what Ted did. ARC’s proprietary keyed rail interface provides the security of an integral rail with the ability to change the amount of taper at any time.
The keyed rail design is actually pretty simple. The rail has a recessed slot that fits precisely over a raised area on the action. When you slide the rail forward, it bumps into the raised section and there is no way it can move forward. That means it’s virtually impossible for the rail to shift under heavy recoil, because it isn’t allowed to move in the direction the recoil is trying to force it.
The Mausingfield action also has 5 beefy screws spread across the rail. The photo below shows a comparison of those to the rail that came with my Stiller Predator action. (Notice the loctite residue on the Stiller screw. I was trying everything I could to keep that rail from sliding around.)
The one drawback of this design is it’s proprietary, so you can’t just use any rail designed for a Remington 700 clone. You have to buy the rails from ARC, but they offer rails with 0, 20, 30, and 40 MOA of cant and can also custom make any other taper you might need.
5) Quick DIY Barrel Swap Option
The Mausingfield is compatible with Savage small shank barrels. That means you can buy a barrel threaded for Savage action, screw it in with a “GO” gauge in the chamber, tighten down a barrel nut … and you’re done. You can literally change a barrel in minutes. Here is a quick video showing the whole process.
The benefit of this design is you can order barrels that are ready to install (already threaded, chambered, and crowned) for just a few dollars more than a barrel blank, and install them without any gunsmithing. Here is just one place that sells these kinds of barrels, and you can buy a Shilen “Select Match” barrel ready to install for $340! That is a benchrest grade barrel, and there is a generous list of cartridges, barrel lengths, and twist rates to pick from. The price for a Shilen “Select Match” barrel blank (not threaded, chambered, or crowned) is $330 on MidwayUSA.com. So for an extra $10, you get the barrel and can bypass what is typically a $300-400 gunsmithing operation.
If you don’t like the Savage barrel nut system, you can still use conventional barrels. In fact, the Mausingfield doesn’t come with a Savage barrel lock nut, but is simply designed to use the same thread as the Savage small shank barrels. It just gives you the option to buy an $18 barrel nut and use Savage-style barrels if you choose.
6) Integral Recoil Lug
Most high-end tactical actions on the market have an integral recoil lug. That just means the lug that keeps the action from sliding back within the stock during recoil is machined as part of the action, instead of being a separate piece. Many shooters believe this results in a more accurate rifle.
7) Remington 700 Compatibility
The Mausingfield is compatible with many Remington 700 components, like triggers, stocks, chassis, and bottom metal. If something is designed to work with a Remington 700 action, there is a good chance it will work just as great with a Mausingfield action. The only exception I’m aware of is Rem 700 scope rails, because the Mausingfield uses a proprietary keyed picatinny rail. It also uses a Savage barrel thread, which is different than the Remington 700 barrel thread.
The Mausingfield is designed to work with Accuracy International’s legendary AICS magazines, which many believe are the best magazines money can buy. I also tested it with Alpha magazines, which are an alternative to AICS magazines that are slightly more compact and lightweight, and they accommodate a slightly longer overall cartridge length.
Results from the Field
Ted sent me a rifle built on his new Mausingfield action, and I took it the field and fire hundreds of rounds of Hornady 6.5 Creedmoor Match Ammo. I fired a lot of rounds at 100 yards, and a lot of rounds at 400-1400 yards. I brought along a few friends and a Surgeon 6.5 Creedmoor rifle that also featured a 22” MTU barrel and a TBAC 30P-1 Suppressor. So we had a good side-by-side comparison.
Both the Mausingfield and the Surgeon were exceptional shooters at 100 yards. 3 different riflemen fired a few 10 shot groups with the Mausingfield, which all measured well below 1 MOA (0.52”, 0.53”, 0.66”, 0.74”). Remember, those are 10 shot groups … so that is exceptional. 3 shot groups were much smaller … but I don’t believe 3 shot groups are a valid representation of a rifle’s precision. If you think you have a 1/4 minute gun, go try to shoot that with a 10 shot string and you’ll see what I’m saying. For more on that topic, I’d encourage you to read this article named “Statistics, Shooting, & the Myth of the 3 Shot Group.”
Here is a look at one of the 10-shot groups I shot with the rifle, which measured 0.52”. It would’ve measured closer to 0.30″ if it wasn’t for the one bullet at the 7 o’clock position (but that wasn’t a called flyer). I don’t claim to have the skill of a benchrest shooter, so I’m sure some could do better with the same rifle. This was also with factory ammo (although it was marked match-grade), so handloads may also be able to further tighten that group as well. While much of a rifle’s precision comes from the specific barrel, ammo, and gunsmith work, it seems clear the Mausingfield action is a very capable foundation for a precision rifle build.
2 Issues Experienced … and Addressed
I don’t want to overstate the couple of minor issues I encountered. The action and rifle was outstanding, except for a couple issues that I noticed and wanted to mention.
Before I test any product, I always explain something to the manufacturer. First, I understand it’s impossible (or at least unreasonable) to build a perfect product. So I don’t want to blast someone if by chance the one unit they sent me had issues, because it may not be representative of their typical product. At the same time, I’m committed to 100% transparency with my readers … that’s one of the big reasons I started this website. I got tired of reading reviews that seemed like nothing more than a paid advertisement. I decided the most fair and honest approach is if an issue is discovered, give the manufacturer a chance to fix it, but also tell the readers exactly what happened, along with how the manufacturer responded and how it finally ended up. So that’s what I did here.
First, I had some issues with ejection. The action wouldn’t always throw a spent case clear of the action. It would occasionally hit the inside of the receiver and kick back into the chamber, and I’d have to manually clear the round. I called Ted about this, and he said that was something they’d already addressed. I had the Mausingfield action with serial number 0001, and they’d already widened the aft section of the ejection port to address this exact issue on subsequent actions. Ted said he wished he would have sent me one of the later models, but they didn’t have one available at the time. Ted filmed a video (below) of him using one of the later models of the Mausingfield action to show this had been addressed, and I was also able to handle one at SHOT Show and it functioned flawlessly.
Second, I had some issues loading rounds from one of my 10 round AI mags. I didn’t have any issues when using the Alpha mags (and I’ve ordered some of those mags personally, because they’re amazing). Once again, I contacted Ted about this and he said this was likely due to the extractor being slightly too tight for that particular batch of brass. He said they’re still working on tuning the extractor, and he prefers to have that part too tight and need to loosen it slightly, rather than for it to be too loose. Ted also demoed an adjusted action functioning perfectly with AI mags in the video below.
Overall, this is a solid product with a few fresh, forward-thinking innovations … and a generous dose of time-tested and field-proven features as well. It strikes a great balance between the best of the old, and something completely new.
The action is now for sale, and is priced at $1,600. For more info visit http://www.americanrifle.com/M5-Mausingfield-Bolt-Action.html.