If you are into AKs then you probably know about the Sharps Bros MB47 milled 7.62x39mm AK receivers. But did you know that recently the company has released the 5.45x39mm version of this receiver called MB74? This new receiver has all the good features of the 7.62mm one but its dimensions are tailored for the 5.45mm AK parts.
Perhaps the most important feature of the MB47 and MB74 receivers is that they have an integral AR-15 buffer tube (receiver extension) mounting provision. It means that in order to attach an AR buffer tube, you won’t need to use adapters. Fewer parts mean simpler and more robust platform. In fact, Sharps Bros has patented the milled AK receiver with built-in AR-15 buffer tube threads.
The Sharps Bros MB74 receivers are made in the USA. They are machined out of solid blocks of 4140 steel. The weight of the block before milling is 15 lbs and after all the machining is done the final product weighs 2 lbs. These receivers are also heat treated to HRC41 hardness.
The barrel journal diameter on these receivers is .866. It will accept press-in barrels with 22 mm diameter of the chamber area. The MB74 receiver is compatible with any stamped or milled AK-74 type parts kits. The manufacturer, however, notes that some fitting may be required.
Here is also a video where John Sharps, the owner of Sharps Bros, shoots a 5.45 rifle built on this new receiver.
The Sharps Bros MB74 receiver is listed on the company’s website at an MSRP of $499. If you visit the page of this product on Sharps Bros website, you’ll find there a link to the Atlantic Firearms website where you can purchase the receiver.
Images from www.sharpsbros.com, www.atlanticfirearms.com