Self-leveling follower and magazine
A follower for a firearm magazine and a method are disclosed. The follower platform is shaped to support a cartridge and has a top surface, a bottom surface opposing the top surface. The top surface defines at least one plane. A normal of the bottom surface defines a vertical axis of the follower. The front end has an interior surface and an exterior surface for engaging a magazine body. The rear end has an interior surface and an exterior surface for engaging the magazine body. A spacer is positioned on the platform. The bottom surface, the front end, and the rear end define a spring receiving space. The spring receiving space is shaped to limit an upper portion of the spring to vertical compression when the upper portion of the spring is compressed into the spring receiving space.
1. A follower for a firearm magazine, comprising:
a platform shaped to support a cartridge and having a top surface, a bottom surface opposing the top surface, the top surface defining at least one plane, a normal of the bottom surface defining a vertical axis of the follower;
a front end associated with a firing direction and positioned on a front portion of the platform, the front end having an interior surface and an exterior surface for engaging a magazine body;
a rear end positioned on a rear portion of the platform, the rear end having an interior surface and an exterior surface for engaging the magazine body; and
a spacer positioned on the platform; wherein
the bottom surface, the front end, and the rear end define a spring receiving space, the spring receiving space shaped to limit an upper portion of a spring to vertical compression when an upper portion of the spring is compressed into the spring receiving space; and wherein
the top surface has an ascending angle of incidence from the front end to the rear end relative to the bottom surface.
2. The follower of claim 1 , wherein:
the spacer has a top surface shaped to support a cartridge being fed to a firearm, the top surface of the spacer angled such that a rear portion of the top surface of the spacer is farther from the at least one plane of the platform than is a front portion of the top surface of the spacer.
3. The follower of claim 2 , further comprising an angle between the top surface of the spacer and the at least one plane of the platform, wherein:
the angle is less than 1 degree.
4. The follower of claim 2 , wherein:
an angle between the top surface of the spacer and the at least one plane of the platform is one of (a) substantially one-half of a taper of a cartridge case to be supported by the follower and (b) substantially one-half of an induced taper of a cartridge to be supported by the follower.
5. The follower of claim 1 , further comprising:
a bolt stop interface projecting from a rear portion of the platform, the bolt stop interface having a stop shelf that is not parallel to the at least one plane of the platform.
6. The follower of claim 5 , wherein:
a rear portion of the stop shelf of the bolt stop interface is farther from the at least one plane of the platform than is a front portion of the stop shelf of the bolt stop interface.
7. The follower of claim 1 , wherein:
at least one of the front end and the rear end comprises at least one fin for engaging a rail in a firearm magazine.
8. The follower of claim 1 , wherein:
the interior surface of the front end forms an obtuse angle with the at least one plane of the platform; and
the interior surface of the rear end forms an acute angle with the at least one plane of the platform.
9. The follower of claim 1 , further comprising:
a spring retention wall coupled to the platform and extending into the spring receiving space between the front end and the rear end, the spring retention wall shaped to limit the upper portion of the spring to vertical compression when the upper portion of the spring is compressed into the spring receiving space.
10. The follower of claim 1 , wherein:
the front end has a front edge that forms an obtuse angle with the top surface and a perpendicular angle to the bottom surface; and
the obtuse angle is between 90.5 degrees and 93 degrees.
11. The follower of claim 1 , wherein:
the rear end has a rear edge that forms an acute angle with the top surface and a perpendicular angle to the bottom surface; and
the acute angle is between 87 degrees and 89.5 degrees.
12. The follower of claim 1 , wherein:
the interior surface of the front end forms an obtuse angle with the top surface of the platform.
13. A follower for a firearm magazine, comprising:
a platform shaped to support a cartridge and having a top surface and a bottom surface, the top surface defining at least one plane of the platform and a normal of the bottom surface of the platform defining a vertical axis of the follower;
a front end positioned adjacent to a front portion of the platform; and
a rear end positioned adjacent to a rear portion of the platform; wherein
an interior surface of the front end and an interior surface of the rear end define a spring receiving space shaped to limit an upper portion of a magazine spring to vertical compression when the upper portion of the magazine spring is compressed into the spring receiving space; and wherein
the top surface has an ascending angle of incidence from the front end to the rear end relative to the bottom surface.
14. The follower of claim 13 , further comprising:
a spacer coupled to the platform, the spacer having a top surface that is at an angle to the at least one plane of the platform such that a rear portion of the top surface of the spacer is farther from the at least one plane of the platform than is a front portion of the top surface of the spacer, wherein the angle between the top surface of the spacer and the at least one plane of the platform is one of (a) substantially one-half of a taper of a cartridge case to be supported by the follower and (b) substantially on-half of an induced taper of a cartridge to be supported by the follower.
15. The follower of claim 13 , further comprising:
a bolt stop interface projecting from a rear portion of the platform, the bolt stop interface having a top surface; wherein
a rear portion of the top surface of the bolt stop interface is farther from the at least one plane of the platform than is a front portion of the top surface of the bolt stop interface.
16. The follower of claim 13 , further comprising:
a spring retention wall extending substantially perpendicularly from the bottom surface of the platform between the front end and the rear end, and shaped to engage an interior region of a magazine spring as the magazine spring is compressed into the follower.
17. The follower of claim 13 , wherein:
the interior surface of the front end forms an obtuse angle with the at least one plane of the platform;
the interior surface of the rear end forms an acute angle with the at least one plane of the platform;
the obtuse angle between the interior surface of the front end and the at least one plane of the platform is between 90.5 degrees and 93 degrees; and
the acute angle between the interior surface of the rear end and the at least one plane of the platform is between 87 degrees and 89.5 degrees.
18. The follower of claim 13 , wherein:
the interior surfaces of the front end and the rear end form perpendicular angles with the bottom surface of the platform to limit an upper portion of the magazine spring to vertical compression when the upper portion of the magazine spring is compressed into the spring receiving space.
19. A follower for a firearm magazine, comprising:
a platform shaped to support a cartridge and having a top surface and a bottom surface, the top surface of the platform defining a first cartridge support plane and the bottom surface of the platform having a normal that defines a vertical axis of the follower;
a front end positioned on a front portion of the platform such that an interior surface of the front end is perpendicular to the bottom surface of the platform and forms an obtuse angle with the first cartridge support plane; and
a rear end positioned on a rear portion of the platform such that an interior surface of the rear end is perpendicular to the bottom surface of the platform and forms an acute angle with the first cartridge support plane, the front end extending further below the platform than the rear end; wherein
the bottom surface, the front end, and the rear end define a spring receiving space, the spring receiving space shaped to limit an upper portion of a spring to vertical compression when the upper portion of the spring is compressed into the spring receiving space; and wherein
the top surface has an ascending angle of incidence from the front end to the rear end relative to the bottom surface.
20. The follower of claim 19 , further comprising:
a spacer extending from the top surface of the platform, the spacer having a top surface defining a second cartridge support plane shaped to support a cartridge casing having a tapered rear portion; wherein
the second cartridge support plane is angled such that a rear portion of the second cartridge support plane is farther from the first cartridge support plane than is a front portion of the second cartridge support plane.
21. The follower of claim 19 , further comprising:
a bolt stop interface projecting from a rear portion of the platform, the bolt stop interface having a top surface that is not parallel to the first cartridge support plane, wherein a rear portion of the bolt stop interface is farther from the first cartridge support plane than is a front portion of the bolt stop interface.
22. The follower of claim 19 , wherein:
the obtuse angle between the interior surface of the front end and the first cartridge support plane is between 90.5 degrees and 93 degrees; and
the acute angle between the interior surface of the rear end and the first cartridge support plane is between 87 degrees and 89.5 degrees.
23. A follower for a firearm magazine, comprising:
a platform shaped to support a cartridge and having a top surface and a bottom surface, the top surface defining at least one plane of the platform and a normal of the bottom surface of the platform defining a vertical axis of the follower;
a front end positioned adjacent to a front portion of the platform;
a rear end positioned adjacent to a rear portion of the platform; and
a spacer coupled to the platform, the spacer having a top surface that is at an angle to the top surface of the platform such that a rear portion of the top surface of the spacer is farther from the top surface of the platform than is a front portion of the top surface of the spacer; wherein
an interior surface of the front end and an interior surface of the rear end define a spring receiving space shaped to limit an upper portion of a magazine spring to vertical compression when the upper portion of the magazine spring is compressed into the spring receiving space.