In my opinion, bullpups are the future. For those that don’t know what a bullpup is, this is a term for a firearm with an action and firing mechanism that is located behind the trigger. They do everything better than the conventional rifle platform by being shorter, more maneuverable, concealable, and consequently, versatile. Desert Tech is a top dog in this niche market that is constantly releasing innovative and quality products: and I have their newest release, the MDRX (Micro Dynamic Rifle Extreme) in 6.5 Creedmoor. Many of you have likely heard of their all-too-familiar MDR already. Well, this new MDRX is basically the same rifle, but improved. How so? Let’s dive into the details!
MDR vs MDRX
The MDR and MDRX are so similar that you can interchange any part between the two. This includes barrels, handguards, and the likes. That said, they are not identical: The MDRX has an improved trigger over its predecessor. This improved trigger has a lighter trigger pull and less creep. This revised model also features a stronger polymer resin that is more resistant to high-impact falls. And because the MDRX is designed to be a workhorse battle rifle, they also improved gas block drainage for better performance in mud and water submersion testing.
The MDRX retains the MDR’s ability to be converted between 223 Remington, 300 BLK, 308 Win. and now, 6.5 Creedmoor. Yes, you are correct in noticing that this is a mixture of small and large frame calibers. This ability alone makes the MDRX very unique and adaptable. And that is without noting that there are aftermarket barrel options.
This new offering also provides another unique option with the MDRX SE which is a side ejecting model. This is for those of you who prefer the simpler, or more conventional ejection system over the MDRX’s forward eject. As with the MDRX, the MDRX SE can be configured to eject on either the left or right side by simply rotating the bolt 180 degrees and swapping the ejection port cover, allowing the gun to be comfortably operated by either right-handers and/or our beloved wrong-handed.
Examining the MDRX
Starting from the beginning, the MDRX is a bullpup, semi-auto rifle that can be configured to fire 223, 300 BLK, 308 Win., and 6.5 Creedmoor at the moment. It takes your standard AR magazines and is totally ambidextrous. Because it’s a bullpup, the MDRX can have a longer barrel than your standard rifle while still maintaining the same length, or even being shorter than said rifle. This gives you the advantage of additional velocity, which is great for hunters, long-range shooters, or military (sometimes a few inches on the barrel is the difference between defeating body armor or not).
Some would question the ergonomics of the MDRX because they have never handled a similar firearm, but I assure you that everything feels natural and all controls are operated familiarly. To release the magazine, you can hit a mag release with your pointer finger, located on either side of the gun above the trigger guard. You can also release the magazine with a button located in front of the magwell; this can be decided by the user based on what feels/works best for them when training with it. A similar trend of options can be seen with the bolt catch. You can drop the bolt using a lever at the rear of the magwell, or slap the charging handle down and continue blasting away. Again, choose whichever method you prefer.
Adjusting the gas block on the MDRX’s short-stroke piston system is great for tuning your particular rifle to specific ammunition, or decreasing gas for use with a suppressor. Thankfully, doing this is also simple. All it takes is a screwdriver, bullet tip, allen wrench, or some other tool to rotate the gas selector to the desired position. Now, you can even access this gas selector without removing the handguard, unlike with the MDR. Total, there are 6 different gas options that you can use to fine-tune your unique setup.
As always, the trigger on this bullpup is going to be a source of a lot of questions and a bit of concern. After firing several hundred rounds through the MDRX, I became familiar with how it felt. I would compare it to your typical mil-spec trigger in any AR15 except it’s lighter than a mil-spec AR.. There is a bit of creep with a slightly mushy break at 4.5 pounds (measured with my Wheeler Trigger Pull Gauge). The trigger reset is very crisp though.
If you don’t know, there is a lot of challenges for engineers to design a streamlined trigger linkage that provides a crisp and light trigger pull safely. Typically, bullpup triggers are on the heavy side so they do not fire when dropped or jostled just right, and being designed as a battle rifle, the MDRX follows this trend. Even though it sounds like I just bashed the trigger on the MDRX, I would place it above most semi-auto bullpup triggers that I have used.
Disassembly and Barrel Swapping
Because the MDRX has been designed to easily convert between calibers and swap barrel lengths, the barrel is extremely easy to remove. Simply loosen the two screws on the side of the gun in front of the ejection port, rotate the barrel lock next to these screws and slide the barrel out of the action. You can also remove the handguard in a similar fashion. loosen the Torx head screws on either side of the handguard and then punch the pin on the underside of the handguard through. Then just pull the handguard off. You can also remove ejection port covers and bolt in a similarly simplistic manner.
Accuracy Testing
I rigged up the MDRX with a 4.5-27×50 Meopta Optika6 and set out my target at 103 yards, measured with a Leupold RX-2800 TBR/W. I then fired several 5 shot groups with a handful of different ammunition types. Below, you can see the average groups from Hornady Match 147 grain ELD-M, Hornady Match 140 grain ELD-M, Hornady American Gunner 140 grain BTHP, Hornady 143 grain Precision Hunter ELD-X, and 130 grainPrime BTHP. Even across the 130-147 grain weight range, my results were pretty consistent in hovering around 1 MOA, which is what Desert Tech claims for the MDRX on their website.
Desert Tech’s Warranty
Desert Tech’s warranty will allow you to return your firearm and get it fixed or replaced at no expense. This will cover any kind of defect in barrels, conversion kits, and firearms from manufacturing or materials for the lifetime of the firearm, regardless of ownership. However, there are some exclusions to what they will cover: they will not cover firearms that have been modified, had aftermarket parts installed, has not been properly maintained or been damaged by high-pressure ammunition or reloads. This warranty applies to any customer in the U.S.A or Canada.
Specifications and Features
- caliber options: 223 Remington, 300 Blackout, 308 Winchester, 6.5 Creedmoor
The following specs are for the 6.5 Creedmoor conversion
- 20″ barrel
- 1:8 twist
- 30″ total length
- 5/8×24 TPI muzzle threads
- 20 round mag included
- accepts SR25 magazines
- 4.7 – 4.5 pound 2-stage trigger
- 9.2 pounds (12 pounds as seen in pictures)
- swappable forward eject
- short-stroke piston operated
- 6 gas block settings (includes suppressor setting)
- ambidextrous controls
- last round bolt hold
- starts at $2,099.98 MSRP
Final Thoughts
I really enjoyed my time with Desert Tech MDRX. The rifle is a prime example of human ingenuity and true innovation. Not only is it unique, but it fills the role that it was designed for perfectly. The MDRX is the ultimate battle rifle because it is short and mobile without giving up barrel length and the accompanying velocity. A longer barrel will also emit less muzzle flash than a shorter comparator which is important for staying concealed.
If you are looking for a hunting rifle, I realize that all points I just made are moot. That said, in light of current events it is becoming increasingly apparent why the second amendment exists. I (and others) would concur that a battle rifle is important to have and to train with, in hopes that you never have to use it to defend yourself and your beliefs. And if it means much to you, I would depend on the MDRX for this purpose and it would be high on my list of preferences.
Learn more about the MDRX and Desert Tech by clicking HERE!
Initially the magazine would eject after firing a round but I bent the magazine catch and desert tech is sending a new one so this issue is resolved to some extent.
The most persistent problem is the cycling of ammo. I have tried 308 Norma, Winchester, Fiocchi, PMC and 762 Magtec, Armscor, PPU. The gunsmith I took the rifle to after 400 rounds stripped it, cleaned it, lubed it and tested it on his range with the ammo he had and experienced the same issues. PMC and Winchester 308 ammo tends to lightly dimple and not fire the primer on the second shot chambered. When you rack it back to clear the unspent round it doesn’t kick out like normal, even if you rack it fast and hard. The unspent round and the next round in the magazines end up jammed in the chamber. Only rarely will the 308 cartridge miss or get stuck in the forward eject system. And the most problematic 308 round is anything with a soft tip. The PPU 762 ammo is getting stuck in the chamber and if the gas is turned up too high it’s ripping the rim off the cartridge. The other 762 ammo frequently gets stuck in or misses the forward eject system but cycles nicely if you leave the forward eject port off. I have requested information on if and how to purchase a 308 side eject panel but received no response. This would be an acceptable fix for the 762 ammo in my mind and I am willing to pay for it. I am not using a high speed camera but I suspect the slightly dimpled non discharge rounds might be the result of a double fire. I have since replaced the trigger with a Jard sear and have not tested yet but Ill keep you posted. Still no idea on how the rifle is putting two 308 rounds in the chamber. Update: third time out shooting with 200 rounds of 308 PMC solid tip, normal gas setting and the new trigger. First off the Jard Sear trigger came from the manufacturer out of adjustment, not your fault but while out of adjustment it produced the same 308 jam as I described above. fires the first round and click on the second round, when you eject the second round it is lightly dimpled. After adjusting the disconnect screw on the new trigger the riffle fires 308 PMC solid tip consistently on Normal gas block setting. 1 out of every 50 will still lead to a jam where there appears to be a misfeed issue.
On the first day of shooting I noticed the trigger would get stuck. In some cases just waiting a second would allow the trigger to spring forward and on others the rifle had to be tapped. Basically the rifle is acting as if I am holding the trigger for a prolonged period of time before resetting and letting pull the trigger again. Upon inspection the trigger rod that connects the front group to the rear assembly has metal burs on the rear of it that appears to be catching on the plastic guides. I removed the rod and polished it smooth. The rear trigger group once removed does not appear to be sticking or rubbing but appears to be wearing excessively. After the first day and 400 rounds the notch in the round pin where the hammer is mounted appears cut into by the trigger latch that is supposed to catch it. As I mentioned above I have replaced the trigger and this issue should be all but removed so this is just for your information.
Also on the first day one of the screws fell out of the left hand side of the rifle, in the desert, and was lost. The manufacturer indicates one is on the way.
On the second day of shooting the cartridge ejection port dust cover hatch started to fall apart. The pin worked it’s way nearly out and it has never worked correctly since. The latch doesn’t hold it closed when you want it closed and the spring doesn’t hold it open when you want it open. The 308 cartridges appear to push past it regardless and I usually have it removed for the 762 ammo.
Initially the rear push pin was removed and reinserted relatively easily, but lately the pin is difficult to remove and the rubber butt stalk end and two halves of the rifle need to be squeezed and manipulated in order to reinsert the pin. I believe the issue above where a 7.62 cartridge was frequently getting stuck between the ejection port and bolt carrier might be putting outward pressure on and deforming the butt of the rifle.
Update!
After my last series of posts I received communication from Jeff Wood of https://coldboremiracle.com/ ([email protected]). Jeff let me know that he is Desert Techs go to repair man and that he could fix it.
I sent the rifle back to the manufacturer and they sent it off to Jeff for repairs. It took about a month and when I received it, the contents where in a new hard plastic case that also include a repair statement from Desert Tech. The statement indicates that a few parts were repaired or replaced and that the 25-round magazine I sent them was incompatible with the rifle as it holds too many rounds. Apparently, you may only use a 20 round or few magazines with this rifle and despite what all the advertisements say the 10-round magazine is the only one that shoots consistently. The statement also indicates that Desert Tech was able to accomplish his diagnosis of “good to go” after firing 20 rounds of 308 and 20 rounds of 7.62 x51… I’m Curious how he was able to diagnose the 25-round magazine and 20 round magazine after only firing 40 rounds but I’m no mathematician. They must have had a bad experience there not telling anyone about.
The freshly returned rifle appeared cleaned and well lubricated. Nothing was done about the factory trigger that appears prematurely warn. The Jard trigger works flawlessly once adjusted. The forward ejection panel that was giving the 7.62 x51 rounds so much trouble appears new and the dust cover flap is now working properly. The magazine catch latch was replace with one that does not appear to have the same poor casting as the original and did not need to be manipulated to work.
On the first trip out shooting after the rifle was returned to me it initially gave me no issues using 10 round magazines shooting 308 or 7.62 x51 cold. As I switch to the 20-round magazine, the gun is already heated up a bit and still on the Normal gas block setting, the 308 rounds start to jam towards the end of the clip (round 16-18). The old cartridge is ejected fine, but the new cartridge is only halfway in the chamber when the action slams closed on it. I adjusted the gas block one setting towards Advanced and I get the same jam. On the final Advanced setting of the gas block the 308 jam is reduced to every other clip. Switching back to 7.62 x51 20-round magazine I set the gas block to Normal and while still hot the 3rd round fired has the rim ripped off the cartridge and left in the chamber. After removing the spent cartridge and cleaning the chamber I call it a day.
The next day I go out and buy the exact same ammo Jeff used to test the rifle. The first two 10-round magazines of 308 go smoothly and then the first 20-round magazine of 308 jams like before on round 17. The second 20-round magazine and the 16th round does not discharge but instead gets stuck in the chamber with the action locked on behind it. So stuck I could not safely dislodge it or tear it down at the range. When I get home and tear it down, I discover the unspent round is the shape of a banana. I’m now getting ready to ship it back to the manufacturer again. I did not get to test the new 7.62 x51 rounds.
In short, this is a $2,500.00 rifle that fails at performing its primary task and the failure of which is somehow out done by its manufacturer who expects you to put over 1000 round thru a faulty weapon in order to make it a slightly less unreliable and do it 10 rounds at a time with multiple months long pauses in-between where the rifle must be sent back to the manufacturer for “repair”…
2nd Update!
As if this couldn’t get any worse, I received communication from Jeff that my riffle never made it to him, he was out of town on a hunt. Desert Tech had someone else perform the warranty work who was out of the loop on the issues I have been communicating. They obviously did not read the two page right-up I sent with the riffle. Furthermore after taking over a week to respond to me this is the response I received from Glen Fullmer:
Good afternoon Scott,
Please find the warranty claim form attached. If you will complete it and get it back to me, I’ll generate another RMA. Please note that if we can’t identify a defect in the rifle or duplicate the issues you’re reporting, we will charge for testing and evaluation ($50), ammunition used, and any shipping/repackaging costs. Thank you.
Glen Fullmer
Warranty Manager
Desert Tech
801-975-7272 Ext. 148
[email protected]
I feel that if anyone should be charging for testing it’s going to be me. So in summary Desert tech is continuing to take the approach of blaming the operator instead of the manufacturer. The continue to negligently push a defective and dangerous product on it’s consumers.
I’m considering a SE model. Does anyone know if the ejected brass will clear the shooters face after a shoulder transition.
If it does not you can easily swap it to forward eject
Before you decide to buy an MDR, everyone needs to know that Desert Tech is a small and poorly managed operation. I waited more than 2 years (while Desert Tech had the full amount deposit) for my MDR. I originally ordered the 223 version, but DT wasn’t delivering them so I took a 308, and had to pay more. The first MDR’s had loads of problems with the gas valve (2 iterations) then a complete rework of the innards. MDR did do a rebuild of my MDR via warranty. You can do a Google search to see the early negative reviews and why the rebuild was necessary. After waiting years, MDR announced it was making conversion kits for the 223 caliber. However, since January, 2020, DT has had my money and still not delivered the conversion kit. Its been 7 months. Consider this when you decide to make your buy.
I’m sure it is a fine rife, as far as bullpups go, but 12 pounds as pictured/$2100, I’m just gonna have to pass. I see absolutely no compelling need for it that any number of other items I have will do just as well or better.
Great concept, but lacking GD&T + QA / QC: New out of the box and without firing a single shot, mine has
1. A miss-aligned 556 gas block (7.62 barrel also displays the same symptom, but was judged “within tolerance”),
2. Binding magazine release after swapping out the Mag Catch, and
3. Handguard not alignment with receiver.
Yes, they are all covered under DT’s lifetime warranty, but the owner must ship it back at his / her own expense ($65.00) for any warranty service. Like my buddies joked, DT must have had so many issues that paying for warranty return shipping would bankrupt the business. My friends are waiting for 3rd or 4th generation instead being beta tester for DT…
Consensus (OK, small sample size of 5) is for 556 caliber, the AUG (and STG556) still offer the best package in weight, balance, ergonomics, and value.
” Desert Tech is a top dog in this niche market that is constantly releasing innovative and quality products: ”
Cough cough…
Ever hear of a little company called, eerrrr what was their name again?
Oh – that’s right – ISRAELI WEAPONS INDUSTRIES…
I’ll take one that’s proven and issued to militaries all over the world – than a “small niche market” (which bullpup rifles are ANYTHING BUT).
While Desert Tech makes cool stuff – and their announcement -> market window is slightly smaller than IWI’s (which took +2 years to release the T-7 and TS-12) – reports in the IWI groups from owners of DT’s stuff, are going to keep me away. And a “lifetime warranty” really isn’t important – if the rifle sits over at DT forever.
Had an issue with my new TS-12 – had a shipping tag in my email 5 DURING the phone call – and it was turned around in TWO DAYS (with FREE NEXT DAY SHIPPING both ways). Doesn’t hurt that I’m friends with their US Sales Rep either – but I didn’t even drop his name on the phone call.
Obviously I am an IWI FANBOI (have an original Tavor, TS-12, T-7 and Galil X39) – but let’s not make DT the sole (or BEST) player in this “niche market”.
Bet Gieselle won’t be jumping on a trigger pack for this anytime soon. Yes – I’m spoiled – If I don’t do the trigger work myself, everything in my rack has either a Gieselle – or a Fulton Binary (for AR pattern triggers – with STEEL PINS so they don’t break).
Decent review though, but let’s not make this into anything more than it is. A “boutique bullpup”. And personally, due to “anecdotal reports” from a number of end users – I’ll TRUST MY LIFE TO MY IWI…
Regards,
Rick
12 lbs.? No thanks…
I did notice the spec weight was 9.2 but as tested was 12 lbs….. would really like to know what the difference was…
IMO, it’s been the trigger pull that has kept me away from ALL bullpup’s, I have seen and tried many, to date NONE have been desirable due to this factor.
Most are atrocious, few are even close to tolerable.
I have a Bushmaster M17S that after a little tinkering has a VERY nice trigger. Just over 2 lbs. (Which with the large rounded trigger pad feels like 6 oz.) and just enough creep to notice if you are really looking for it, otherwise it is imperceptable.
I own a IWI Tavor SAR 18 and initially the trigger was heavy and mushy, however, after a couple aftermarket upgrades (Geissele trigger pack and Lightning Bow Trigger) the trigger pull now is crisp at around 5 lbs as opposed to the 8-9 lbs it was initially.
Sure I had to spend more to get the trigger how I wanted it but most bullpups are meant for the military and thus are at a minimum minute-of-man accurate at range. The MDRX seems to be shooting at just over 1 MOA…
So, IMHO, if minute-of-man accuracy is good for the military than I don’t mind it being the bare minimum for me and since most firearms can be modified to shoot better, I don’t mind my minimum being there
Well, there are two different opinions…
I’d like to see it run through dirt water sand storms before it’s okay too much internally covered uncleanable
I have owned a Kel Tec RDB 223 for three years. I quickly became my favorite platform. It is short enough to defend a house easily but with a 16 1/4 barrel retains full velocity. The Kel Tec RDB and RFB as well as the Tavor from IWI have been on the market for some time . I still believe Kel Tec has been the innovator. The trigger on the RDB is excellent and the downward ejection facilitates shooting from either shoulder. Some complain that controls are difficult on Bullpups but it is just a matter of using the platform a few days.
Got to have this one!
It’s garbage like this one that gets all gun owners in trouble… All it will take will be one idiot…
Let me get this straight… You’re a gun owner, and you’re complaining about people buying cool and innovative guns instead of old hunting rifles? You’re too scared of the anti-gun lobby trying to spank us over the actions of one miscreant to approve of the use and sale of “asssaaauuullltttt riiiiffflllleeesss!!!!!” (as if it matters)? This is the exact attitude that turns new people away from the firearms community. And this is coming from a 21 year old who has gotten tens of people introduced to firearms, including scary black guns. I enjoy hunting as much as the next guy, but remember hunting isn’t why the second amendment exists. My generation is very mindful of this.
Well said sir, well said indeed!
Agree very well said brother
Young men like you will be how this nation stays free.
In my life time we have restored rights that did not exist when I was 21.I hope from the next world I can see what people like you accomplished when you are my age
The peanut gallery is down the hall, you’re excused.
Please enlighten me…
How is this garbage?
Garbage? Doubtful. Ostensibly, to you, the MDRX is just a scary gun. Maybe you’d be more comfortable having the government mandate which guns the citizen should be allowed to purchase? Not me. The MDRX isn’t on my wish list but I fully support the right of any lawful gun owner to purchase and own one.
“All it will take will be one idiot…”
Repeat it’s only a tool, only a tool.
With this sort of inflammatory statement you should back it up with some sort or level of imperial evidence… otherwise why make this sort of statement, you just come angry and ignorant???
Exactly was thinking the same thing….just a FUDD
And you don’t think some idiot that uses an M14 or bolt action rifle won’t do the same….?
Don’t pay attention to Jeffrey. He’s just an agitator stirring the pot and trying to get a reaction…. Which he did.
You sound like another Libturd that just happens to own a gun because you haven’t voted yourself out of one yet. What you know about guns can comfortably fit in a mosquito’s a$$. If you’re going to make ALL gun owners seem like IDIOTS, do all of U.S. a favor, SDSTFU and keep your ignorance to yourself.