Tag Archives: 308

Suppressed Weapon Systems MISB 308Win for the SRS

I swore off shooting unsuppressed long ago, and I only do it occasionally by choice. The suppressor bug bit me hard many years ago, and I have never vanquished its effects. With that in mind, I am always thinking about better ways to hush the noise of my favorite pastime. Who would have thought that an idea I had depreciated would turn my jaded eye.

One of my most favorite rifles of all time, is my old Desert Tech SRS A1. I have run countless barrels through it, I currently have somewhere between ten and fifteen barrels of assorted different calibers. Factory, custom, and even a few specialty barrels. Even with all those options, I still love my old 16” 308 Winchester Covert barrel. The calm and consistent performance of the 308 is like an old friend, so when I got the opportunity to try yet another great 308 Winchester option for my favorite rifle, I jumped at it.

Suppressed Weapon Systems has been in the suppression business for some time. They specialize in the integration of suppression technology directly into the firearm, instead of making the suppressor just a muzzle device. Their MISB (Monolithic Integrally Suppressed Barrel) is available for many different firearms, including my dearest SRS. The modularity of the SRS family of rifles makes it ideal to pair with technology like the MISB, and with a durable cartridge like the 308, it would last for some time.

I’ve often tinkered with the idea of an integrally suppressed barrel for my SRS, but I was always worried about spending the money on an NFA item that would get burnt out and need to be replaced. A valid concern I had always thought, but the MISB is constructed in such a way that the tube can easily be removed and installed on a new barrel/baffle stack. So with my main concern assuaged, I dove in with both feet.

The Suppressed Weapon Systems MISB for the SRS is manufactured from a Bartlein Barrel blank, well know for great quality and precise shooting. The muzzle is cut at a determined length, in my barrel’s case, around sixteen inches. But the remainder of the barrel blank is then cut into the suppressor baffles. The length of the barrel to the breach of the muzzle is fluted, and drilled, I assume to decrease weight but also to add an expansion chamber for venting high pressure gas.

The outer tube of the MISB is a good fit, but not entirely tight, this was a bit of a concern for me at first but I later learned it was necessary to free-float the barrel. Having the outer tube captured and tightened with the barrel would add stress and torque to the overall structure. The tube is sealed at both ends with what appears to be Viton high temp fluoroelastomer O-rings. The muzzle end of the MISB has a threaded cap also sealed with the O-ring, it is knurled and has cuts for torquing it into place with a tool. Its an impressive example of machining design and ingenuity.

I couldn’t wait to get the barrel mounted in my rifle chassis, and test its performance. As soon as I got home with it, I hurried to my basement man-cave and installed it into my SRS. I found the fit to be a bit snug, perhaps more-so than any other barrel I’ve tried. Its easy to get a burr on the shank of SRS barrels, one must be careful. But that was not the case with the MISB, it was simply just a bit tight. Perhaps a slightly smaller diameter would help, but I found it to be consistent, so it was a minor inconvenience. It was the same when I mounted it in my SRS A2.

Once mounted, I headed for the hills to get the rifle zeroed with this new barrel. As usual, it was an easy process. Most SRS chassis will change POI with a different barrel, but it is rarely off by more than a few inches. So a quick re-zero on my scope was easy, and in no time I was using the rifle to shoot steel at 710 yards.
SWS guarantees sub MOA accuracy for three shots with their MISB system, but suggests that 1/2 to 3/4 MOA is expected more often than not. I found my barrel to be consistent with that.

The suppression quality of the barrel was on par with what I expected. The first round pop was significant, but quickly forgotten with successive shots. The slender barrel looks very handsome in my A1 with the longer handguard. A few inches longer than a standard twenty-two inch barrel which pokes just out of the handguard. When mounted in my Covert A2, it was a few inches longer than the standard Covert sixteen-inch barrel when fitted with the DTSS Suppressor.

I think the SWS barrel offers a great option for those looking for a slender and inconspicuous barrel to keep things quiet. At $2200 for a barrel, it is no small investment. But it’s also not much different than a good barrel fitted with a suppressor would cost you, and SRS owners are gluttons for dropping coin on good barrels. And the fact that you can reuse the tube on a new barrel blank having no interaction with the Federal agency everyone loves to hate makes it even more appealing. I look forward to using it even more in the future.

The Desert Tech MDRX

Advancing technologies have made every part of the firearm and shooting industry better, with new materials, better production equipment, and a growing competitive market all driving forward it is no wonder that so many new and exciting products are available today. Desert Tech has been pushing those limits since its inception in 2007, and this year they have released another great product that follows the Desert Tech adage Tomorrow’s Weapons.

The MDRX is the next generation rifle from Desert Tech, it builds on the already popular MDR rifle they released in 2016. The MDRX is a short-stroke piston operated semi-automatic bullpup, for those who don’t know already, a bullpup is a rifle configured such that the action, magazine, and firing mechanics are all located behind the trigger. The purpose of this design gives the MDRX a shorter overall length than conventional rifles of the same barrel length. When you add in the other additional features of the MDRX the difference becomes even more apparent.

All Desert Tech rifles are designed with modularity in mind, and as such, they are all available as multi-caliber chassis and barrel combinations. The MDRX shares that same heritage, as it stands at the moment it is available in four different calibers from the factory; 223 Wylde, 308 Win, 300 BLK, and 6.5CM. All four of these barrel conversion kits can be interchanged in the same chassis, making the MDRX one of the few modern sporting rifles to accept both large and small frame calibers. All this from an SBR sized weapon without the stamp.
Being a semi-auto bullpup adds some challenges when it comes to universality, these challenges were overcome with ingenuity. The MDRX is completely ambidextrous, all of its controls are mirrored on both sides of the rifle for both right and left-handed shooters. In addition to the ambi controls, the rifle has a forward ejecting system that sends spent brass casing forward away from the shooter. Previous bullpup designs eject brass to the right side, which in a bullpup is a bad thing if you are left-handed. The MDRX can be fired from the right or left side with no concern of catching hot brass to your face. And if you are a dedicated left-hand shooter, you can swap ejection from forward right to forward left in just a few seconds.
The MDRX comes standard with a compensator made by Desert Tech called The Ratchet, the compensators are caliber specific to provide the best performance in recoil reduction and to stop muzzle rise.
One of the major challenges with bullpups is creating a good clean trigger pull, this is due to the linkage required to connect trigger shoe to the sear pack. This is another challenge that was overcome with design ingenuity, and the resulting trigger feel of the MDRX is widely accepted as great. Of the many people who have pulled the trigger on an MDRX, the common consensus is that it is a good trigger, not just for a bullpup, but a good trigger period.
The MDRX has a six-position adjustable gas valve allowing the operator to tune the rifle to whatever ammunition they might use, as well as use the rifle with a suppressor and a lower gas setting.
The MDRX’s aluminum/polymer chassis construction features full-length upper Picatinny rail, M-LOK slots for accessories and flush-mounted QD sling cups on the rear of the receiver. It is also designed to accept most AR-15 style magazines, and for large frame calibers, it uses SR-25 pattern mags. The rifle ships with caliber appropriate P-mags from Magpul.
The various caliber conversions for the MDRX feature popular twist rates, and standard barrel thread for adding muzzle accouterments. There are also both sixteen-inch, and twenty-inch barrels available in several of the assorted calibers, giving shooters different performance options. And with different barrel lengths, there are two different handguard lengths to go along.
The ambidextrous charging handles of the MDRX are non-reciprocating, they are normally locked to the front in a spring-loaded detent. They can also be locked to the rear by pulling them back and up, the release is as simple as slapping either of the handles down, and the bolt carrier closes into battery. The gun locks open upon firing the last shot from the magazine, the bolt release is centrally located right behind the magwell. This allows for very quick reloads by simply extending the thumb when seating a fresh magazine, thus closing the bolt on a fresh round. This actually can make reloading faster than most AR-style rifles due to fewer steps in the reload process.
The forward ejection system is perhaps the most curious of all the MDRX’s features. The open-faced bolt extracts the spent case and carries it to the rear, as the carrier travels it engages the ejector with a dovetail lug on either side. The momentum of the carrier then pulls the scissor-like ejector out, and it swipes across the open bolt face pushing the spent case off and into the ejection chute opposite. There it is retained by a spring-loaded pawl until the bolt carrier again travels forward where a protruding lug pushes the spent case forward and out the ejection chute. It’s a very interesting system, the only flaw I found with it is that when unloading an unspent cartridge from the rifle, it does require a firm stroke of the charging handles to get the cartridge seated firmly in the ejection chute. This is not so much a flaw as much as it is a training practice needed to be followed. The ejection system is designed to be used on either side of the rifle, both the ejector and chute can be swapped from one side to the other in seconds.

The MDRX SE utilizes a standard side ejection system

Also new for 2020 is a new side ejecting MDRX, for those who prefer a simpler, more traditional ejection pattern. The side eject is available in. 223 Wylde only, and can also be swapped from right to left side ejection. There is also the added benefit of a lighter overall weight, and a less expensive price tag.

On the Range
With several barrels in hand, I took the MDRX into my mountain hide to test its function. I started out shooting with the sixteen-inch 308 Win barrel, and loaded with Fiocchi 150 Grain FMJ ammunition at one hundred yards. After zeroing the sights, I fired a few five-shot groups, which ended up being around two MOA in size.
I continued firing the rifle at several additional targets to see how it ran. I found the recoil to be much softer than the previous similar rifles I had shot, this surely had much to do with the Ratchet compensator. The trigger was very clean and crisp, the reset is quite audible, I attribute that to the highly conductive poly receiver who’s hollow construction makes a very resonant chamber. I fired several additional groups using additional ammunition types as well, American Eagle XM80 as well as some 168 Grain match ammo from both Hornady and Federal. The match grade ammo certainly provided better groups, they averaged right around one MOA.

The MDRX seen with 20 inch 6.5CM barrel and longer handguard

So with several hundred rounds through the rifle, and a respectable shooting and zeroed rifle, I figured it was time to test the metamorphosis of this multi-caliber gifted rifle. The barrel is removed from the MDRX using a five-millimeter hex wrench, the rifle comes with one, but I prefer to use the suggested eighty-inch-pound torque limiter. After removing the handguard via two loosened screws and one take-down pin, the barrel is released by loosening the two barrel clamp screws by about one turn, and then disengaging the barrel lock 180 degrees to allow the barrel to slide out the front of the chassis. The bolt must be locked open to the rear to complete this operation. I then installed the twenty-inch 6.5 Creedmoor barrel, seating it firmly towards the breach. The process is then reversed, turning the barrel lock 180 degrees, and then torquing the two barrel clamp screws to 80 inch-pounds with a torque limiter. Followed by re-installing the handguard, which I had swapped out for the longer one. The rifle had just transformed from a sixteen-inch 308 Winchester into a twenty-inch 6.5 Creedmoor, and I was excited to see the increased performance. The point of impact would not be the same from one barrel to the next, but it was on paper at one-hundred yards, so it only took some minor corrections.
The 6.5 Creedmoor shot very well, with 140 Grain ammunition from both Hornady and Desert Tech, the groups averaged much better, in the sub to half MOA realm. With this kind of accuracy, I couldn’t wait to take the MDRX out to more significant distances.

For several hours the rifle neatly piled up brass right in front of my shooting mat, the rifle never malfunctioned, and just kept eating magazine after magazine of ammunition. I also fired some S&B 140 grain ammo through the rifle without any problems, I would have liked to try some lighter loads like a 120 grain, but I didn’t get the chance.

A typical 5 shot group from the MDRX 223 Wylde 40 Grain Fiocchi (100 Yards)

The rifle is easily swapped to smaller caliber barrels as well, the 223 Wylde and 300 Blackout do require a little more though.
A change of the bolt, a magwell spacer, and a swap of the ejection chute are required in addition to the barrel change.
The 223 Wylde shot just as good as the 6.5 Creedmoor, sub MOA groups were easy when shooting good ammo.

The great performance of the MDRX was hard to deny, it is a very compact rifle, with incredible reach, and good accuracy. Desert Tech has upped the game with this rifle, and they stand behind all their rifles with a lifetime warranty. It would be a great rifle whether you are hiding in a tree stand, need a behind the seat truck gun, or anywhere you’d need heavy firepower in a compact package. Its larger calibers are certainly useful for big game hunting and some distant shooting, while the smaller calibers are great for quick target shooting in a 3-gun style competition or varmint hunting. The MDRX carries a higher than average price tag, but that is because it brings so much more to the table. The multicaliber option alone actually saves money by consolidating your training, and less money spent on optics and accessories. You literally could do almost every American shooting activity with this one rifle. Whether it is a home defense rifle or a suppressed ranch rifle, the MDRX is a do-all rifle if ever there was one.


ES Tactical 6.5Creedmoor Barrel for the MDR

Just when I thought I was up to my ear’s in MDR, Eric Smith from ES Tactical found it expedient to dump another huge helping of MDR in my lap. It wouldn’t take long to figure out which way this would go.

As a guy with too many irons in the fire already, I took the 6.5 Creedmoor barrel with a grain of salt (I know you all feel my pain). Had it not been for my stellar experience with Eric’s work, I might have even backburnered this project. But instead, I took the first opportunity to stab my MDR with this latest addition to the pile.

Ive shot the MDR quite a bit, some might even say more than anyone else. The MDR is a multi caliber bullpup rifle. The rifle was first available in 308, it will soon be available to the public in 223. But for those of you that already have the gun, you can wet your multi caliber whistle without waiting by ordering a 6.5 Creedmoor from ES Tactical. I shot quite a bit of 308 in the beginning, and I loved having so much power in such a little package. With the 308 barrel installed, the MDR can put down a serious amount of hate and anger. But it is still quite capable of MOA accuracy, and at distance as well. Just a short while ago, the 223/556 conversion was made available to me. In the short time I spent with it, I became very enamored. The minimal recoil, and outstanding accuracy made the compact MDR even more desirable, you can read more about that here.

So you can imagine my excitement when the option came to try out the Creedmoor in my beloved little rifle. The Creedmoor offers the same accuracy as the other cartridge options, but less recoil than the 308, and a better envelope for distance as well.

I couldn’t resist the appeal, so I hurried up to my local shooting hole, and warmed up my trigger finger. Upon arrival I ran a few magazines of 223 through the rifle, just to get my trigger finger into shape, then set to swap the rifle over to the Creedmoor.

The MDR as seen with 223rem barrel (installed with YHM Turbo) Sixteen inch 308win, and the ES Tactical eighteen inch 6.5CM barrel

Since the 6.5 and the 308 share the same boltface, magazine, and a few other parts, there is only a need for a barrel assembly should your rifle be a 308. Since my rifle was currently a 223, I had to swap bolts, remove the magwell block and switch the magazine catch.
To see how the MDR is converted from one caliber to another click here

It took a few minutes, and I was ready to make some noise. Except I wouldn’t. I hate shooting without the proper muzzle accoutrements, so I attached one of my favorite suppressors, the Silencerco Hybrid. The barrel assembly from ES Tactical came with a six position gas key, allowing for refined tuning of the rifle. I found it quite unnecessary to figet with, as the rifle functioned flawlessly, it consumed and expelled everything I fed it.

Speaking of diet, I tried a few different things. I started out with Desert Tech munitions 140 grain match, I have always had good luck with it, and today was no exception. I also tried some of the more popular brands, such as Hornady 120 Grain Match As well as the gold standard Federal Gold Medal Match 130 grain And the very popular Prime 130 Grain Match

The accuracy results from this fine selection varied slightly, the DTM, and Hornady gave the best results. Both of them printed groups that were mostly hole, and little paper. The Prime and Gold Medal were not too far behind, it is my guess that the Berger and Norma 130 grain bullets used may perhaps be a bit more finicky with seating depth. Which may explain the larger patterns. DTM shown in blue, Hornady in red, Federal in yellow, and Prime in green

As you can see in the groups the stringing is horizontal on the better ones, it seemed to follow the heating of the barrel. The first three or four shots in each group were either touching or stacked. It was usually the fourth, fifth or sixth shot that were the outliers (I may have lost count a few times, I was enjoying myself😌). The lesser groups didnt seem to have any particular pattern. I only ran a chronograph on the DTM 140 grain ammunition, the average over a couple magzines worth of ammo showed 2610fps. I was quite pleased with the velocity from this 18 inch barrel, with a MV like that, coupled with MOA or better accuracy, this thing would be very useful for anything inside 1000 yards.

Being as familiar as I am with the platform, I have gotten used to it’s quirks and folleys. This familiarity has helped me avoid some of the little things that cause malfunctions, so it didn’t surprise me at all that I experienced no failures. I did note that the brass was coming out pretty dirty but otherwise fine, I suppose I could have dialed down the gas pressure a little after all.

The thread protector, threads, and crown of the ES Tactical 6.5Creedmoor barrel

In total, I shot probably 80 or so rounds (not counting the 223 appetizer). It was smooth shooting, the recoil was very mild, and with the suppressor mounted up, I could shoot all day. This setup would be awesome for a threegun carbine, it’d also make the perfect truck gun, or patrol rifle. So many possibilities, I doubt it will be long before the next flavor MDR comes along.

Should you find youself in need of a Creed for your MDR, give Eric a call over at ES Tactical, and dont forget he cuts awesozme barrels for your SRS, or just about anything else you might want too.


Here is the video: