Foxtrot Mike is well known for its innovative 9MM PCC, as it has been a go to for competitive PCC shooters and consumers alike, for more than 6 years. The Foxtrot Mike Products AR-15 Gen 2 Upper Receiver is a premium quality upper receiver designed with several innovative and patent-pending features that make it one of the most innovative AR-15 uppers on the market. The integrated, proprietary recoil system allows for the upper to function without the need for a lower with a buffer tube, making it a great option for AR style firearms, that incorporate a folding or collapsible stock. The Foxtrot Mike Products Mike-15 Gen 2 Upper Receiver is available in 5.56/223 Wylde and features a forward charging handle that is easy to operate and offers improved ergonomics compared to a traditional charging handle. It is is designed to provide superior performance and functionality to AR-15 enthusiasts. The reduced reciprocating mass, lighter weight, and higher pic rail on the gen 2 Mike 15 Upper receivers (.250” taller than Mil spec), allow shooters to experience an AR style rifle with less recoil, and quicker follow up shots due to flat shooting recoil impulse. The integrated recoil system is simple and utilizes Direct Impingement gas system. The proprietary bolt carrier is light weight and shorter than a standard AR15 bolt carrier. The carrier key (gas key), has an integrated recoil lug, which has a mating pocket in the proprietary bolt carrier. This ensures no recoil load during cycle is distributed to the gas key screws. The recoil springs have a “nested” inner spring (6 pound) ,and outer spring (12 pound) , both wound in opposite directions, to ensure they move freely during cycling of the firearm. Inside the nested recoil Springs is the recoil rod. The lightweight proprietary Gen 2 Bolt Carrier Group ride along the Recoil Rod as the gun cycles. The Lightweight M-Lok compatible handguard, has an interlocking tab with the upper receiver, ensuring proper alignment with the bore. Two Torx bit screws hold the handguard in place for simple maintenance without risk of stripping screws. An extra long, lightweight barrel nut improves torsional support to longer handguards during hard use. 4 position, non reciprocating charging handle, can be mounted on either side of the handguard, to accommodate left and right handed shooters. The charging handle is located in the best possible location for ergonomics, as it is located near your hand on the handguard. This allows shooters to clear malfunctions, check the chamber or make ready, all while looking downrange at your target. The “trolley” is the steel carriage the 4 position charging handle attaches too. The Trolley resides inside the hand guard, it is a round tube machined from steel, with a 4” deep .160” hole down the center of it. The recoil rod goes into the trolley when the charging handle is pulled rearward. The 4 position Charging Handle has redundant attachment methods, should one fail. The Charging Handle is held in place by (2) 10-32 set screws, which are installed from the front of the handguard using a 3/32” allen wrench. The trolley also has a threaded end which also compresses against the 4 position charging handle from the rear of the charging handle. The Mike-15 gen 2 Upper Receivers allow consumers to use their existing AR style Mil Spec Lower Receiver and combine it with the included Picatinny Rail Adapter and they can convert there vanilla M4 to a modern Buffer-less firearm, capable of using a collapsible or folding stock, and being able to be fired from the folded position should the need arise. Its unique features and accessories make it an excellent choice for those looking to build a custom AR-15 pistol or short-barreled rifle Sleek, Modern light weight design combined with premium materials, to produce an accurate, simple and reliable product at an amazing price. Premium 41V50 Barrel, vacuum stress relieved, button rifled 1-8 twist rate, Burnished .223 Wylde Chamber, coated in Melonite (QPQ). 9” Pistol length gas, 12.5” Mid Length gas, 13.9” Mid Length gas, 16” Mid Length gas and 16” Intermediate Length gas available. Proprietary Bolt Carrier machined from pre-hard 4342, machined then post vacuum heat treated to increase hardness and maintain excellent surface finish of gas ring bore of Proprietary Bolt Carrier. Integrated recoil Lug in the carrier and gas key, greatly improving shear strength of Gas key screws. Proprietary double pinned gas block with interlocking feature, ensures proper alignment of gas block. The Gas Block has its gas port drilled from the top, so we can confirm alignment of gas port in barrel, port in the gas block and gas tube are all aligned prior to assembly. Monolithic Style lightweight sleek modern buffer-less Ar style Upper Receiver, simple elegant direct impingement operating system allowing costumers to use the included picatinny rail adapter to transform their vanilla M4 into a Modern Buffer-less AR. Taper Lock Barrel nut, and extra long lightweight Barrel nut, allow for excellent handguard rigidity and accuracy in a lightweight package. Proprietary Firing Pin Spring, using S7 Tool Steel Firing Pin, and S7 Tool Steel Extractor Pin. An S7 Tool Steel Round Cam Pin and S7 AR-15 Extractor are also utilized. All Mike-15 Gen 2 Upper Receivers come with an easy to install Picatinny Rail Adapter included. This allows consumers to convert their vanilla M4 into a modern, lightweight, flat shooting buffer-less firearm, by using their own Mile Spec AR Lower Receiver and the included Picatinny Rail Adapter. Foxtrot Mike machines 6 flats (standard box wrench shape) on the chamber end of the barrel. We slide the 6 sided flats into a plate with a mating shape, so we can apply 150 pounds of torque to the barrel extension, without having to clamp down onto a round profile with a 10 ton press. This guarantees all the torque is applied to the barrel extension, guaranteeing proper torque values on every barrel.