DY12 Shotgun

The DY12 is a gas-operated semi-automatic 12-gauge shotgun featuring an upper and lower receiver made from 7075 T6 aluminum. It provides AR-15-like ergonomics and controls, eliminating the need to retrain your mechanics for 3-gun competitions or target shooting. The shotgun is magazine-fed with a 5+1 capacity for 2-3/4” and 3” shells.

Thread Pitch 
The DY12 features a metric right-hand thread of M24x1.

Trigger Pull Weight
The trigger pull weight of the DY12 is between 4 and 4.5 kilograms.

Length of pull (LOP) 
The length of pull for the DY12 is 14-1/2 LOP.

Rail 
DY12 has picatinny rail system.  Please note that some fittings may be required. 

The DY12 upper receiver:  Slots .205” to .208”, Rails .230” to .208”, Width .825”. 

The DY12 slots are identical to Picatinny, while prior versions not under DY12 differ slightly where all don't work.

Most single lug sights will go on the rails. If the sights have two lugs the spacing between the slots comes into play and the sights will not go on unless the guns rails are modified. 

DY12 Receiver 
The DY12 does not have the same receiver width as the AR15 type receivers. 

Shooting with bean bag round 
DY12 will not shoot with bean bag round. 

Shooting Armor Piercing 

Using armor-piercing ammunition in the DY12 depends on the load; it must be sufficiently heavy and powerful to operate the action. The gun can handle it, but the functionality of the shot shell is uncertain.

Shooting Steel Shot 

Avoid using a full choke when shooting steel shot in the DY12, as it may lead to barrel jamming. Use the appropriate choke, such as Modified or Cylinder.

Barrels 
All Derya shotguns, including the DY12, feature chrome-lined barrels. The bore size measures 0.719 inches.

Gas port 
The DY12 features a gas port with a diameter of 0.120 inches.

Chokes and sizes

• Full (.680”) -  Lead shot only
• Modified (.701”) - Lead and Steel shot only
• Improved Cylinder (.722”) - Will shoot anything including slugs 

Safety

When the safety is engaged, the bolt cannot be retracted as it is blocked by the sear.

To remove the DY12 safety, unscrew the set screw and detach the lever.

Barrel Shroud
DY12 barrel shroud is constructed from aluminum. It is not pinned and can be unscrewed, relying solely on the knurling of the shroud and the nylon bushings.

Retaining Screw or Nut thread pitch
The thread in barrel retaining screw of DY12 is M8 x 1.25. 

Pistol Grip Screw Size 
DY12 grip screw is 6mm x 1.0 thread. 

Buttstock Screw Size 
DY12 buttstock Screw Size is M6x1, 31 MM long.

Buffer Tube Weight
DY12 Buffer Tube Weight is 1.5oz.

Recoil Spring Weight/Poundage 
DY12 Recoil Spring Weight/Poundage is 13lbs +\~ 1lbs .

Handguard Sizes 
DY12 factory handguard / Short is 12.5” while the extended handguard is 16.5”.

Optics and Scopes we recommend
Holosun 510c, Vortex Crossfire, SigSauer Romeo5.

Buffer Tube - the Buffer tube is Mil Spec

Forearm grip 
We do not offer and not recommend installing a forearm grip as it sometimes block the gas system causing cycling issue. 

Machining and Finishing Process
DY12 Barrel is made of 4140 Annealed Extruded Steel. Heat treatment is applied, followed by crack inspection, then drilling, and finally machining.

All Aluminum is 7075. Receiver specifically is machined from a solid block.

All significant components are made in house in our machines.

For finishing, anodizing and melonite is done in our factory in Türkiye. In USA, finishing is done by premium finishing company most other USA companies use.

Choosing Your DY12 Piston: Go By Shell Length

Your DY12 ships with two gas pistons — light and heavy. Picking the right one is simpler than most shooters expect. You don't need to chase velocity numbers, dram equivalent, or load type. Just match the piston to your shell length:

• 2¾" shells → light piston
• 3" shells → heavy piston

That's the whole rule.

It's the same approach longstanding shotgun manufacturers built their reputation on, and it holds because shell length is the most reliable proxy for how much gas a load dumps into the system. The light piston lets lower-pressure 2¾" loads vent enough gas to cycle the action reliably. The heavy piston meters the extra gas that 3" magnum loads generate, keeping the action from running over-driven — which means smoother cycling, less felt recoil, and less long-term wear.

Set the piston by the box you're shooting, then leave it alone. It's a straightforward, field-proven approach — and it won't let you down.

DY12 Ammo Recommendations

The DY12 is a gas-operated, magazine-fed 12-gauge, and like every gun in that class it runs best on quality ammunition with enough energy to work the action. A few simple guidelines will keep yours cycling cleanly:

• Aim for 1,250 fps or higher. Across the mag-fed semi-auto shotgun category, roughly 1,250 fps is the accepted floor for reliable cycling, and manufacturers of comparable AR-platform 12-gauges advise the same. Improper cycling is often caused by ammunition producing a muzzle velocity under 1,250 fps. For best function, high-power shells of 1,250 fps or higher are recommended. Full-power buckshot and slugs run reliably as well.
• Favor high-brass / high-velocity loads. Cheap, low-velocity rounds often don't cycle well, and around 1,250 fps is a rough minimum for smooth operation. High-brass hunting and defensive loads give you the most consistent results.
• Go easy on the cheapest target loads. Very light birdshot loads built for trap and skeet are the most likely to give a mag-fed semi-auto trouble. If you want to shoot light 2¾" target loads, run the light piston and expect to keep the gun clean.
• Pick smooth-hulled shells. Twelve-gauge shells were never designed to feed from a box magazine, so look for smooth casings with a more rounded nose for the most dependable feeding.
• Buy quality. Premium loads engineered for mag-fed guns — such as Federal Action Shotgun — are built specifically to feed and eject without malfunction, and they're worth it when reliability matters. This category of ammunition was developed because mag-fed shotguns posed real challenges in finding shells that cycle near 100%.
• Break it in. As with any gun in this class, expect the action to smooth out over the first few hundred rounds.

The short version: feed your DY12 quality 12-gauge in the 1,250 fps-and-up range, match the piston to your shell length, keep it clean, and it'll run.

Watch DY12 Cycling Tutorial

Frequently Asked Questions for DY12:

Differences between DY12 and VR80 - The DY12 adheres to Mil Spec standards. It features a genuine AR grip, includes QD rings, and comes with a standard Picatinny rail. The DY12 has an adjustable stock, unlike the VR80, which has a fixed stock. It also has distinct packaging and disassembles in a different manner.

How many rounds will the magazine on my Model DY12 hold? The magazine capacity is two, five and ten rounds. But  21 round drum magazine is available in our web shop. 

Where is the serial number located?  DY12 - The serial number is located on the left side of the upper receiver.  

I just bought a Derya DY12 and removed the barrel shroud. What are the thread size and pitch for the muzzle threads and the threads that secure the barrel shroud? The Derya DY12 barrel has M24 x 1 -6g threads at the muzzle and TR25 x 2 trapezoidal threads that hold the barrel shroud.

I don't see my firearm, item number, UPC, or color listed for DY12, where is it? On our website, we only list the type of firearms, as each type might include up to 10 different items. Variations exist due to different color exclusives and varying magazine capacities to comply with state gun laws. Below are all the item numbers, UPCs, and special information: If an item number starts with a number followed by an "L", it indicates a magazine limitation from the standard item. If an item number ends in "US", it means the firearm was Made in the United States. If an item number ends in "TR", it signifies the firearm was made in Türkiye.

DY12 Video Training & Tutorials

• Derya DY12 Shotgun Basics: Safe Handling and Operation Tutorial

   

• Derya DY12 Shotgun Field Stripping and Assembly Tutorial

   

• Derya DY12 Shotgun Choke System Tutorial

• Derya DY12 Shotgun Magazine Cleaning Tutorial

• Derya DY12 Shotgun Telescopic Stock Tutorial

• Derya DY12 Shotgun Reloading Techniques Tutorial

• Derya DY12 Shotgun Changing Pistons Tutorial

• Derya DY12 Shotgun Troubleshooting Techniques Tutorial

• Derya DY12 Shotgun Cleaning and Maintenance Tutorial

• Derya DY12 Shotgun Mounting and Accessories Tutorial

• Derya DY12 Compensator Installation Guide