Magazine spring and magazine assembly

Abstract

A spring for a firearm magazine includes a top attachment leg, a plurality of upper coils connected to the top attachment leg, a plurality of intermediate coils below the upper coils, and a bottom attachment leg below the plurality of intermediate coils. The upper coils are sized and shaped to nest within the intermediate coils when the spring is fully compressed, reducing the solid height of the spring. In some embodiments, at least two complete upper coils and/or at least two complete lower coils nest within intermediate coils. In one example, at least some coils have a rectangular coil shape. The spring can be configured for use in a handgun magazine or a rifle magazine, for example. A handgun magazine and a magazine components kit including the spring are also disclosed.

1 . A spring for a firearm magazine, comprising:
 a top attachment leg;   a bottom attachment leg; and   a plurality of intermediate coils between the top attachment leg and the bottom attachment leg;   wherein the spring extends along a central spring axis and at least some of the individual coils of the plurality of intermediate coils have a rectangular coil shape that includes straight side segments connected between straight end segments, wherein each of the straight side segments and each of the straight end segments is inclined to a horizontal when the spring is at free length with the central spring axis oriented vertically.   
     
     
         2 . The spring of  claim 1 , wherein each of the straight end segments is inclined at an angle of at least 10° when the spring is at free length. 
     
     
         3 . The spring of  claim 1 , further comprising:
 a plurality of upper coils between the plurality of intermediate coils and the top attachment leg, wherein at least two of the plurality of upper coils nest within the plurality of intermediate coils when the spring is fully compressed, and wherein the top attachment leg nests within the plurality of upper coils and the bottom attachment leg nests within the plurality of lower coils when the spring is fully compressed.   
     
     
         4 . The spring of  claim 1 , further comprising a plurality of upper coils between the plurality of intermediate coils and the top attachment leg, wherein the upper coils have an oval coil shape. 
     
     
         5 . The spring of  claim 1 , further comprising a plurality of upper coils between the plurality of intermediate coils and the top attachment leg, wherein the upper coils have a rectangular coil shape. 
     
     
         6 . The spring of  claim 5 , further comprising lower coils between the plurality of intermediate coils and the bottom attachment leg, wherein the lower coils have a rectangular coil shape. 
     
     
         7 . The spring of  claim 6 , wherein the lower coils are sized and shaped to nest at least partially within the plurality of intermediate coils when the spring is fully compressed, and wherein each of the straight end segments is inclined at an angle of at least 10° when the spring is at free length. 
     
     
         8 . The spring of  claim 1 , further comprising:
 a plurality of upper coils between the top attachment leg and the plurality of intermediate coils; and   a plurality of lower coils between the plurality of intermediate coils and the bottom attachment leg.   
     
     
         9 . The spring of  claim 8 , wherein the spring has from 9 to 11 coils. 
     
     
         10 . The spring of  claim 9 , wherein the spring has a maximum solid height of not more than 6 wire diameters. 
     
     
         11 . The spring of  claim 10 , wherein a front portion of the spring has a solid height of not more than 4 wire diameters. 
     
     
         12 . The spring of  claim 11 , wherein the wire diameter is from 1.2 mm to 1.4 mm. 
     
     
         13 . A magazine parts kit comprising:
 the spring of  claim 1 ;   a magazine base plate;   a follower having a lower rear margin that is inclined with respect to the horizontal; and   a spring plate configured to nest with the magazine base plate,   wherein the magazine base plate has a base plate body with a top surface that defines a recess sized and shaped to receive the spring plate such that the spring plate is recessed into the base plate body.   
     
     
         14 . The magazine parts kit of  claim 13 , wherein the follower configured such that a front portion and a rear portion of the follower overlap the intermediate coils when the spring is fully compressed. 
     
     
         15 . The magazine parts kit of  claim 14 , wherein one or both sides of the follower are cut away to accommodate the intermediate coils when the spring is fully compressed. 
     
     
         16 . The magazine parts kit of  claim 13 , wherein an underside of the follower defines a protrusion configured to engage the top end portion of the spring, wherein the protrusion is laterally offset from a center of the follower. 
     
     
         17 . A magazine comprising:
 a magazine tube extending along a central axis from a bottom end to a top end having feed lips;   a follower retained in the magazine tube;   a base plate on the bottom end of the magazine tube;   a spring plate with a plate body; and   a spring retained within the magazine tube between the spring plate and the follower, the spring including a top attachment leg, a bottom attachment leg, a plurality of upper coils, and a plurality of intermediate coils between the plurality of upper coils and the bottom attachment leg;   wherein the spring extends along a central spring axis and individual coils of the plurality of intermediate coils have a rectangular coil shape that includes straight side segments connected between straight end segments, wherein each of the straight side segments and each of the straight end segments is inclined to a horizontal when the spring is at free length with the central spring axis oriented vertically.   
     
     
         18 . The magazine of  claim 17 , further comprising a plurality of lower coils between the plurality of intermediate coils and the bottom attachment leg, wherein when the spring is fully compressed, at least two upper coils nest within the plurality of intermediate coils, the top attachment leg nests within the plurality of upper coils, and the bottom attachment nests within the plurality of lower coils. 
     
     
         19 . The magazine of  claim 17 , wherein the straight end segments are inclined at an angle of at least 10° when the spring is at free length. 
     
     
         20 . The magazine of  claim 19 , wherein at least some coils of the plurality of lower coils nest within the plurality of intermediate coils when the spring is fully compressed.