IP Library › Granted Patent US 12,736,305
Granted Patent B2
US 12,736,305 · App. 19/245,711 · Granted Sep 15, 2026

Back-up sights with compact aperture, centering sight post, and miniaturized windage detent mechanism

Inventors: Zachary Freeman (Westminster, CO); Eric Nakayama (Broomfield, CO); Timothy Eric Roberts (Broomfield, CO)
Assignee: Magpul Industries Corp.
F41G1/033F41G1/08F41G1/17F41G1/18F41G1/26
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Quick Facts
Patent No.
US 12,736,305
App. No.
19/245,711
Granted
Sep 15, 2026
Kind
B2
Abstract

A sighting system for a firearm and related methods are disclosed. The sighting system has front and rear flip-up sights, wherein the front sight comprises a flip-up portion having an aperture through which a sight post can partially extend; a knob comprising one or more notches on a first side and the sight post extending from a second side; at least one detent arranged to face and interact with the one or more notches. The knob is configured to rotate about a first axis, where the rotation causes the sight post to move in a first direction along the first axis; tilting of the knob in a second direction based on the detent interfacing with the notches; and tilting of the sight post in the second direction, thereby forcing at least a portion of the sight post to press against the aperture, or a combination thereof.

Claims (39)

1 . A method for manufacturing a rear flip-up sight for a firearm, the method comprising:

providing a sight assembly comprising:

a base;

two vertical arms extending from the base, forming an opening between the two vertical arms;

a windage screw passing through the two vertical arms;

an aperture mechanism positioned within the opening, the aperture mechanism having a first aperture and a second aperture of different sizes; and

configuring the aperture mechanism to rotate 180° around the windage screw to achieve aperture selection between the first and second apertures; and

installing a threaded tab along the windage screw, the threaded tab interfacing with a biased detent and configured to move laterally in response to rotation of the windage screw, thereby adjusting a lateral position of the aperture mechanism, as guided by the biased detent, and avoiding lateral shift during the aperture selection.

2 . The method of claim 1 , further comprising:

aligning the first and second apertures along a common vertical axis by configuring the threaded tab to laterally adjust the aperture mechanism as the windage screw is rotated.

3 . The method of claim 1 , further comprising:

forming the aperture mechanism with a unitary structure having non-threaded tabs that slidably engage the windage screw to allow the aperture selection without introducing lateral shift.

4 . The method of claim 1 , wherein rotation of the windage screw causes the threaded tab to move laterally and adjust a position of the aperture mechanism without misalignment of the first aperture and the second aperture when the aperture mechanism is rotated 180°.

5 . The method of claim 3 , wherein the windage screw is coupled to a windage knob, and wherein the windage knob comprises a leaf spring with a plurality of detents and wherein the plurality of detents are shaped to engage with a plurality of notches spaced along a perimeter of the windage knob.

6 . The method of claim 5 , wherein the windage screw and the threaded tab are configured to laterally shift the aperture mechanism in response to rotation of the windage knob.

7 . The method of claim 3 , wherein the aperture mechanism is configured to maintain alignment along a vertical axis when switching between the first and second apertures, reducing lateral shift.

8 . The method of claim 5 , wherein the aperture mechanism is configured to rotate around the windage screw with minimal or no lateral movement along the windage screw when flipped between the first and second apertures, and the windage screw moves the aperture mechanism laterally when the windage knob is rotated.

9 . The method of claim 5 , wherein the leaf spring has a radius less than a radius of the windage knob.

10 . The method of claim 5 , wherein the threaded tab interfaces with the biased detent via a notch and wherein the interfacing between the notch and the biased detent is configured to guide lateral movement of the threaded tab along the windage screw.

11 . The method of claim 5 , further comprising a circular boss on one of the two vertical arms.

12 . The method of claim 11 , wherein the circular boss includes a concentric recess for receiving the leaf spring.

13 . The method of claim 5 , wherein the plurality of detents are angled.

14 . A method for manufacturing a rear flip-up aiming sight, the method comprising:

providing a sight assembly comprising:

two arms;

an aperture mechanism comprising:

first and second sighting apertures of differing diameters; and

first and second non-threaded pivot apertures oblique to the first and second sighting apertures; and

installing:

a windage screw passing through the two arms and the first and second non-threaded pivot apertures with a threaded tab between the first and second non-threaded pivot apertures and threaded to the windage screw; and

a biased detent configured to guide lateral movement of the threaded tab along the windage screw, wherein the aperture mechanism is configured to rotate 180° around the windage screw to switch between the first and second sighting apertures.

15 . The method of claim 14 , further comprising:

aligning the first and second sighting apertures along a vertical axis by configuring the threaded tab to laterally adjust the aperture mechanism as the windage screw is rotated.

16 . The method of claim 14 , further comprising:

forming the aperture mechanism with a unitary structure having non-threaded tabs that slidably engage the windage screw to allow the first and second sighting aperture switching without introducing lateral shift.

17 . The method of claim 14 , wherein rotation of the windage screw causes the threaded tab to move laterally and adjust a position of the aperture mechanism without misalignment of the first sighting aperture and the second sighting aperture when the aperture mechanism is rotated.

18 . The method of claim 16 , wherein the windage screw is coupled to a windage knob, and wherein the windage knob comprises a leaf spring with a plurality of detents and wherein the plurality of detents are shaped to engage with a plurality of notches spaced along a perimeter of the windage knob.

19 . The method of claim 16 , wherein the aperture mechanism is configured to maintain alignment along a vertical axis when switching between the first and second sighting apertures.

20 . The method of claim 18 , wherein the aperture mechanism is configured to rotate around the windage screw with minimal or no lateral movement along the windage screw when flipped between the first and second sighting apertures, and the windage screw moves the aperture mechanism laterally when the windage knob is rotated.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Apr 7, 2026
From: FREEMAN, ZACHARY; NAKAYAMA, ERIC; ROBERTS, TIMOTHY ERIC
To: MAGPUL INDUSTRIES CORP.
Reel/Frame 074293/0537 →
Continuity (4)
Continuation 18482520 · Oct 6, 2023
Continuation 17802245 · Aug 25, 2021
Provisional Application 63070357 · Aug 26, 2020
Related Publication 20250314456A1 · Oct 9, 2025
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