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The Corvus Defensio M1 Receiver Rail offers a long, solid mounting solution for the attachment of optical aiming devices, iron sights, laser designators and other accessories.  Unlike the AR15 receiver and handguard rails the Corvus Defensio M1 Receiver Rail is solid (monolithic) from front to rear.  Unlike the original Steyr AUG A3 rail the Corvus Defensio M1 Receiver Rail reaches almost to the ejection port, making it easier to use short eye-relief optics. It is equipped with two QD-Sling Swivel attachment points and an interface to directly mount ACOG rifle scopes.


•    Long Picatinny Rail for mounting various accessories (optics, magnifiers, BUIS, electronic attachments, lasers, etc.).
•    The rear end of the rail extends almost to the ejection port allowing the use of very short eye-relief optics.
•    Machined slot for mounting 3x and 4x Trijicon ACOG rifle scopes directly to the rail, lowering the height of the optic relative to the bore.  This is especially useful when using a piggyback red dot sight (less offset).
•    Integral limited rotation QD Sling swivel attachment points (also suitable for snap hooks, paracord, etc.).
•    Maximum sight radius of approximately 240 mm (9.5”) when using iron sights.
•    Made of hard anodized 7075 aluminum.
•    Length: 260 mm (10.24”)
•    Weight: 146 gm (5.15 oz)


•    Separate receiver from stock.
•    Remove Barrel.
•    Heat the three screws of the original Picatinny rail mount with a heat gun to release the factory thread locker.
•    Remove the original Picatinny rail.
•    Attach the Corvus Defensio rail (preferably using the new rail mounting screws that are attached).

Note:  It is recommended to apply thread locker to the screws before the final assembly since otherwise, they could loosen during use!

For detailed instructions with pictures click here.

This product will only work with M1/SE versions of the Steyr AUG.

Additional Information

Customer Reviews

Great asset for the AUG Review by AJ
I needed a lower rail for my AUG to lower my acog/ rmr a little because the high rail for the AUG puts the rmr on top of the acog a bit too high for my liking. So I thought I’d give this a try. The rail has built in holes and an acog notch cutout in the rear of the rail for specifically mounting an acog. The only issue I had with it was if you mount the acog directly to the rail it pretty much brings the acog reticle down too low to be able to see the reticle. I didn’t realize the rail had the option to mount the acog to it when I ordered it and was counting on using my bobro low mount anyway. So it worked out well that way anyway and I still have the option to take my optic off should I need to. If you mount an acog to this rail directly, you will have to take the rail off off the gun to get the scope off should you want to. All in all I’m very pleased with this rail and it did exactly what I wanted it to. It brought my acog down enough to give me a better way to see my rmr and it’s even long enough to mount some BUIS if you like. Solid rail. Looks good, works well and adds a lot of versatility to this rifle. Love it! And don’t forget the awesome placement of the new QD swivels built in to the rail. (Posted on 5/25/2018)

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