Welcome to the proud family of Desert Tech firearm owners. In acquiring your new MDR (Micro Dynamic Rifle), you are the owner of the most versatile autoloading rifle in the world. To get the most out of your MDR rifle, please read this manual from cover to cover before handling and operating the rifle for the first time. TABLE OF CONTENTS FIREARM SAFETY............................................................................................................................................................
g) Magazine Spacer Removal.............................................................................................................................................................................................................................. 30 PARTS EXPLODED VIEW ..................................................................................................................................................................................................... 57 h) Conversion Kit Installation.......
SAFETY SAFETY FIREARM SAFETY WARNING! KEEP OUT OF REACH OF CHILDREN! IT IS DANGEROUS TO ALTER OR MODIFY THIS FIREARM IN ANY WAY. ANY ALTERATION OR MODIFICATION OF THE FIRING MECHANISM WILL RESULT IN THE FIREARM BECOMING UNSAFE. ANY ATTEMPT TO ALTER OR MODIFY THIS FIREARM WILL NULLIFY ALL WARRANTIES. THE USE OF REMANUFACTURED OR RELOADED AMMUNITION OF ANY KIND WILL ALSO VOID ALL WARRANTIES. 6 ALWAYS keep the firearm pointed in a safe direction.
SAFETY SPECIFICATIONS Weight (Rifle weight with conversion) Rifle empty, no magazine: .223 Wylde .300 BLK .308 Win TBD TBD 8.35 lb (3.79 kg) Length (Rifle length with conversion) REMEMBER: TREAT ALL FIREARMS AS ALWAYS LOADED. LOOKING INTO THE END OF THE BARREL (MUZZLE) IS NOT RECOMMENDED AT ANY TIME. Minimum Length with 16” Barrel: .223 Wylde .300 BLK .308 Win 26.2” (66.55 cm) 26.2” (66.55 cm) 26.2” (66.55 cm) Length with 16” Barrel and flash hider: .223 Wylde .300 BLK .308 Win 27.75” (70.
FACTS ABOUT THE MDR KEY FEATURES Portable The MDR has unrivaled portability because it is lightweight, compact, ergonomic, and balanced, with an overall length of 26.2” with a 16” barrel and a weight of 8.35 pounds. Adaptable WARNING: Carry out the following operations before dismantling: Move safety selector to “Safe” remove the magazine, open the bolt and visually ensure the chamber is clear (page 23).
4. 7. Insert the barrel assembly into the MDR receiver, barrel extension end first with the gas block rail at the 12 o’clock position. When properly seated in the receiver, there should be around a 1/16” (1.5mm) gap between the front edge of the upper receiver and the back edge of the gas block. (Fig. a-6) 8. Release the bolt assembly by pressing the charging handle downward to disengage it from the locked-back position.
c) Handguard Installation b) Gas Adjustment 1. To set the gas setting to Normal, rotate the gas valve within the gas block until the “N” is centered over the detent and clicks into place. (Fig. b-1) 2. To set the gas setting to Adverse, rotate the gas valve within the gas block until the “A” is centered over the detent and the gas valve clicks into place. (Fig. b-1) 1.
5. d) Ejection System The MDR may also be fired without the chute panel, in which case the empty cartridges will eject in the standard 90-degree fashion from the rifle. Be careful to note which side it ejects from in this configuration, as hot casings may potentially hit the shooter’s face while firing if the ejection port is on the same side as the shooter’s head.
RIFLE OPERATION Function Check, Loading, Reloading, Unloading, Firing b) Loading To load the MDR, first ensure it is in a safe environment to do so, observing all the rules of firearm safety, and the safety selector switch is in the “Safe” position (page 11) Ensure the cartridges loaded into the magazine match the chambering of the conversion kit. 2. Insert cartridges into the magazine by pressing the cartridge (parallel to the magazine) downwards into the magazine.
Ensuring the MDR is on “Safe” and pointed in a safe direction, insert the loaded magazine (bullets forward, Fig. b-1) into the magazine well until it is seated with an audible “click” sound. A quick tug down on the magazine is advisable to ensure it’s locked in position. 5. Grasp the charging handle, press down and pull all the way to the rear of the charging handle channel, then release. Do not slowly release, or “walk”, the bolt forward, as it may not fully seat the cartridge in the chamber. 6. 2.
When on target and ready to fire, rotate the safety selector switch to “Fire.” (Fig. d-1) 4. Squeeze the trigger until the rifle fires. Release the trigger so it resets, and repeat the process until the magazine is empty or until desired firing is complete. f) Unloading / Clearing 1. Fig. f-1 e) Reloading Fig. d-1 2. The MDR comes with two ambidextrous options for releasing the magazine. 1a.
CALIBER CONVERSION / DISASSEMBLY / REASSEMBLY a) Conversion Kit Removal 1. Using the T25 side of the multi-tool, loosen the handguard retention screws. Press the captured handguard retention pin through from the right side to the left side of the MDR receiver until it snaps into position. (Fig. a-1) 2. Slide the handguard off the front of the MDR. (Fig. a-1) 3. Lock the charging handle to the rear of the charging channel. 4.
b) Bolt Head Removal / Bolt Carrier Group Disassembly 1. FPRP Tilt the bolt carrier group upwards and drop the firing pin out. (Fig. b-1) Firing Pin 1. When swapping the bolt head during a caliber conversion, ensure the bolt head caliber label on the extractor matches the chambering of the conversion kit being installed. (Fig. c-1) 2. Follow the Bolt Head Installation / Bolt Carrier Group Reassembly steps on page 28 for bolt head installation instructions.
d) Bolt Head Installation / Bolt Carrier Group Reassembly 1. Note: Ensure the caliber on the bolt head matches the barrel you have installed. (page 12, Fig. a-5) 2. 3. 4. Rotate the bolt head to approximately the 1 o’clock position and insert the bolt guide pin, with the top plate of the pin parallel to the bolt carrier. (Fig.
Using a small flat tool, tap the back of the magazine conversion bar until it slides off. (Fig. f-2) 3. 1. Insert the barrel assembly into the MDR receiver, barrel extension end first with the gas block rail at the 12 o’clock position. When properly seated in the receiver, there should be a 1/16” (1.5mm) gap between the front edge of the upper receiver and the back edge of the gas block rail tower. (Fig. h-1) CONVERSION & REASSEMBLY CONVERSION & REASSEMBLY Press the .223/.
4. 6. 7. On the MDR handguard, pop the captured handguard retention pin out to its open-most position. (Fig. h-5) CONVERSION & REASSEMBLY CONVERSION & REASSEMBLY 5. Ensuring the bolt head is fully forward, install the bolt carrier assembly into the back of the MDR upper receiver first ensuring the charging handle is forward.
DESERT TECH REFLEX OPTIC (DTRO) b) Using and Zeroing the DTRO a) DTRO and DTRO Mount Installation 1. Fig. a-1 To turn the DTRO on, press the button at the front of the optic. To turn it off, press and hold the button for approximately two seconds. (Fig. b-1) 2. The DTRO takes a CR2032 3v battery. It is located on the bottom of the optic. Once mounted, optic removal will be necessary to change the battery. (Fig. a-2, page 34) The DTRO has two adjustment screws, and two lock screws.
6. To move the dot down or up, use the included screwdriver to turn the top screw counter-clockwise or clockwise, respectively. (Fig. b-4) 7. After each zero adjustment, re-tighten the lock screws to ensure no zero shift occurs during firing. ADVANCED DISASSEMBLY a) Bolt Head Disassembly 1. L Fig. b-3 MRO 2. Separate the extractor spring assembly from the extractor by pulling it off the extractor. (Fig a-2) 3.
b) Bolt Head Reassembly CAUTION: Before reassembling the bolt carrier group, ensure you have the correctly chambered extractor for the conversion kit you intend to install (Fig. b-1). Failure to comply can cause malfunctions, internal damage, or a complete failure of the firing cycle. Press the extractor bump stop into the extractor spring. (Fig. b-2) 2. Press the extractor spring assembly onto the extractor spring catch point, until it snaps in position. (Fig. b-3) 3.
CLEANING AND MAINTENANCE d) Gas Block Reassembly 1. GENERAL Install the piston into the gas block, pressing it to the rearmost position. (Fig. d-1) Fig. d-1 2. ADVANCED Install the gas valve in the front of the gas block with the firing condition rib at the 12 o’clock position, then rotate it until the detent clicks into the desired firing condition setting. (Fig. d-2) Use a punch tool to depress the detent to allow initial rotation.
a) Receivers b) Bolt Carrier Group (Assembled) 1. Separate the upper receiver from the lower receiver by popping out the three (3) captured takedown pins. (Fig. a-1) 1. Remove the bolt carrier group, ejector panel, and chute panel by following the steps on page 24-25. 2. With a brush and CLP, scrub the magazine well, then wipe it clean with a rag. 2.
5. Re-apply CLP to the bolt carrier, bolt body, bolt guide pin, firing pin, and firing pin lock, extractor cutout, bottom bolt carrier guides, and spring guide. (Fig. c-1) c) Bolt Carrier Group (Disassembled) 1. Disassemble the bolt carrier group by following the steps on page 26. 6. Reassemble the bolt carrier group following the steps on page 28. 2.
f) Ejector Panel and Chute Panel (Assembled) e) Gas Valve 1. Remove the chute panel and ejection panel by following the steps on pages 16-17. 1. Remove the gas valve from the gas block by following the removal steps on page 39. 2. Apply CLP to the insides of the chute panel and ejection panel, then, with a wire brush, scrub the insides of the chute and ejection panels.
g) Storage WARNING! KEEP OUT OF REACH OF CHILDREN! 1. Ensure the rifle chamber is clear and the magazine is unloaded and the rifle is on ”S” (Safe) position. 2. If possible, store rifle in a gun safe, with the butt of the stock resting on the ground and the muzzle pointed up. 3. If a safe is unavailable, store in a secure location, ensuring it is out of reach of children. TROUBLESHOOTING a) Failure to Fire WARNING: If the rifle fails to fire with a live 2. Empty chamber (loaded magazine).
b) Failure to Feed from Magazine *Rifle jams with empty chamber Malfunction 4. Bolt not fully closed. 5. Dirty firing mechanism, defective firing pin, or defective striker assembly. 6. Barrel not properly seated. Malfunction Pull charging handle all the way to the rear and release. 1. Malfunctioning magazine. Possible Causes: -Dirty -Poor ammunition -Ammunition out of spec -Worn recoil spring 2. Magazine improperly seated. Check for sluggishness of operation. Clean.
Malfunction 5. Triple feed. Remedial Action Remove the magazine, then pull and lock the charging handle to the rear. Observe the chamber check window to confirm a the chamber is clear. Cycle the bolt multiple times to ensure all rounds have been cleared, then insert the magazine, charge the rifle, and resume firing. If a round or multiple rounds continue to get hung up in the receiver, remove the chute panel and clear the malfunction by hand. 52 5. Triple feed.
Malfunction 2. Cartridge stuck between bolt carrier and chute panel. Remedial Action Malfunction Remedial Action Remove the magazine, pull the charging handle to the rear and tilt the rifle upwards in a safe direction. 2. Cartridge stuck between bolt carrier and chute panel. (continued) If the problem still persists, it may be the ammunition is out of spec. If none of the above remedy the malfunction, contact Desert Tech Warranty to discuss the next step.
Malfunction 6. Malfunctioning extractor. 7. Improper gas block setting causing the bolt to short stroke. 8. Worn extractor or extractor spring. Clean extractor (see pages 43-45). Verify proper extractor for installed conversion kit. Rotate gas block to the proper position for shooting conditions. Replace extractor or extractor spring. 1. Flash Hider 2. Barrel 3. Handguard 4. Gas Block 5. Charging Handle (Right and Left Side) 6. Picatinny Rail 1 7. Upper Receiver 8. Ejection Panel 9. Cheekrest 10.
Upper Receiver 1 2 5 3 4 6 78 9 1. Charging Block Screws 2. Pivot Link 3. Charging Handle Roll Pins 4. Charging Pivots (Left and Right) 10 5. Coil Spring Pins (2) 6. Charging Handle (Right and Left Side) 7. Charging Handle Springs (2) 8. Charging Handle Detent Pins (2) 9. Charging Block 10. Mounting Thread Plate 11. Upper Receiver 12. 8-32 Receiver Screw (8) 13. Mounting Bracket 14. Mounting Bracket Torx Screws (4) 15. Barrel Block Torx Screws (8) 16. Vent Plug (2) 17. Retaining Ring 18.
Barrel Assembly Bolt Carrier Group 1 1 2 1. Barrel Extension 2 1. Operation Rod Guide 2. Operation Rod 2. Barrel 3 3. Gas Block 4. Bolt Head Assembly 4. Gas Piston 4 5. Gas Piston Ring 8. Gas Block Taper Pin (2) 5. Bolt Guide Pin 5 6. Gas Valve 7. Flash Hider 3 3. Recoil Spring 6. Firing Pin Retainer (FPRP) 6 7. Firing Pin Retainer O-Ring 8 4 8 8. Bolt Carrier 9. Firing Pin 10.
Bolt Head Ejection Panel 1 1. Ejector Action Spring 5 2 1. Extractor 3 3. Extractor Buffer 5. Bolt Head 4 2 3. Ejector Pin 4 5 4. Counter Link 5. Ejection Carriage 2. Extractor Spring 4. Extractor Dowel Pin 1 2. Extractor Link 8 6 3 6. Retention Screws (2) 7 7. Ejector Release Spring 8. Ejector Panel Release Tab 9. Stationary Pin 10. Cross Link Pin 11. Ejector Panel 12. Ejector Carriage Return Spring 13. Ejector Spring Rod Guide 10 14.
Chute Panel Handguard and Pistol Grip 3 2 1 1. Chute Panel 2. Chute Panel Release Tab 1. Handguard 3. Retention Screws (2) 2. Handguard Nut (2) 4 4. Chute Panel Release Spring 3. Handguard Screws (2) 5. Dust Cover Pin 6. Dust Cover Spring 7. Dust Cover Detent Pin 8. Dust Cover Detent Spring 6 4. Takedown Pin Clip 5. Takedown Pin 16 6. Pistol Grip 15 7. Pistol Grip Screw 9. Dust Cover E-clip 10. Chute Dust Cover 1 2 8. Pistol Grip Cap 14 3 11. Coiled Spring Pin 12.
Conversion Kit 1. Barrel Assembly 2. Bolt Head Trigger Group 1. Second Stage Lever 1 2. Trigger Axle 3. Magazine Conversion Bar 1 3 3. Trigger 4. Magazine Insert (For .223 and .300 BLK kits) 5. Chute Assembly 2 4.
Sear Assembly Semi-Automatic Desert Tech Reflex Optic (DTRO) and DTRO Mount 1 3 1. Hammer 2. Hammer Spring 3. Sear Axle Pin 4. Sear Spring 1. DTRO Screws (2) 5 1 4 2 6 2 2. DTRO 8 9 7 3. Battery 4. DTRO Seal Plate 5. Sear 5. DTRO Mount 6. Sear Bushing 6. DTRO Rail Mount Screw 7. Sear Housing 7. DTRO Rail Mount Nut 3 4 8. Hammer Catch 9. Hammer Catch Spring 11 10 5 10. Sear Housing Pin (3) 11.
DESERT TECH WARRANTY POLICY -Desert Tech warrants to the initial retail purchaser that for three (3) years from the date of purchase, your Desert Tech SRS A-1, SRS A-1 Covert, HTI, MDR, including the chassis, conversion kits, scope mounts, muzzle brakes and magazines will be free from manufacturing defects in workmanship and/ or material.
Notes: 72 Notes: 73
Notes: 74 Notes: 75
