A rifle having a receiver alignment system includes an upper receiver and a lower receiver configured to engage with each other in an assembled configuration by aligning and pressing an exterior portion of the upper receiver into an interior portion of the lower receiver. A cavity is defined within the interior portion of the lower receiver configured to receive the upper receiver. A lug positioned on the upper receiver defines an alignment groove formed on a lower surface of the lug. A plunger pin is provided in a hole defined within the interior portion of the lower receiver. The plunger pin is configured to engage with the alignment groove and generate a spring-loaded tension when the upper receiver and the lower receiver are engaged in an assembled configuration.

A pistol slide, including an upper part configured to guide a barrel of the pistol, a lower part configured to guide a recoil spring guide rod and a recoil spring, wherein the upper part and lower part are manufactured independently and coupled together to serve as the pistol slide.

A pistol slide, including an upper part configured to guide a barrel of the pistol, a lower part configured to guide a recoil spring guide rod and a recoil spring, wherein the upper part and lower part are manufactured independently and coupled together to serve as the pistol slide.

Quick take-down firearms and methods of using quick-take down firearms. The quick-take down includes an upper receiver coupling and a barrel coupling. The quick take-down can be unlocked by sliding a sliding lock collar in a translational motion to an unlocked position to release locking elements from a locked configuration. In the unlocked position, a barrel and handguard may be installed onto and removed from the upper receiver of the firearm. Releasing the sliding lock collar returns it to a locked position, securing the barrel and handguard to the upper receiver.

Quick take-down firearms and methods of using quick-take down firearms. The quick-take down includes an upper receiver coupling and a barrel coupling. The quick take-down can be unlocked by sliding a sliding lock collar in a translational motion to an unlocked position to release locking elements from a locked configuration. In the unlocked position, a barrel and handguard may be installed onto and removed from the upper receiver of the firearm. Releasing the sliding lock collar returns it to a locked position, securing the barrel and handguard to the upper receiver.

There is a multi-caliber weapon system. The multi-caliber weapon system comprises: a frame body, with a front body portion, a middle body portion, and a rear body portion, and including: a plurality of frame flanges, each frame flange being coupled to an interior of the frame body and extending upwardly therefrom; a barrel, removably coupled to the front body portion of the frame body, including: a plurality of barrel rings, each barrel ring being disposed around a circumference of the barrel and spaced along a length of the barrel, wherein the barrel rings are disposed on the frame flanges; a chamber, removably coupled to the middle body portion of the frame body, and removably coupled to the barrel; and a bolt, removably coupled to rear body portion of the frame body, removably coupled to the chamber, and including: a bolt face, removably coupled to a front bolt portion.

There is a multi-caliber weapon system. The multi-caliber weapon system comprises: a frame body, with a front body portion, a middle body portion, and a rear body portion, and including: a plurality of frame flanges, each frame flange being coupled to an interior of the frame body and extending upwardly therefrom; a barrel, removably coupled to the front body portion of the frame body, including: a plurality of barrel rings, each barrel ring being disposed around a circumference of the barrel and spaced along a length of the barrel, wherein the barrel rings are disposed on the frame flanges; a chamber, removably coupled to the middle body portion of the frame body, and removably coupled to the barrel; and a bolt, removably coupled to rear body portion of the frame body, removably coupled to the chamber, and including: a bolt face, removably coupled to a front bolt portion.

Firearm pin retainer plates and pins have a frame defining an internal space, a moving action part defining a bore and connected to the frame within the space, a pivot pin connected to the frame and to the action part such that the action part pivots with respect to the frame, the pivot pin having a cylindrical body portion closely received in the bore and defining a pin axis, the pivot pin having a first flat surface portion, a retention element connected to the frame within the space and having a first retention facility adapted to engage the first flat surface portion to prevent rotation of the pin with respect to the frame. The pin may have a second flat surface portion opposed to the first flat surface portion. The first retention facility may define a slot having opposed edges operable to engage the first and second flat surface portions.

Trigger module securing apparatus using internally threaded pins and threaded fasteners to secure a trigger module into the lower receiver of a rifle.

Apparatus, systems, and methods for the maintenance, repair, modification, cleaning, disassembly, and reassembly of firearms and firearm components are disclosed. Particular embodiments include tools to aid in the removal and insertion of an extractor pin from the bolt assembly of an AR-15 or M-16 rifle. Preferred embodiments are directed to bolt assemblies for .223 and .308 imperial caliber firearms, as well as 5.56 and 7.62 metric caliber firearms. The tools include a housing with a channel to receive the bolt, a channel to insert a locking rod to orient and secure the bolt in the housing, a channel for inserting a removal rod to remove the extractor pin from the bolt or an inserting rod to insert the extractor pin into the bolt.