Bolt Buffer and Firearm

Abstract

Firearms and buffer systems having a second buffer spring or having a buffer spring and a buffer adjusting nut, for instance, to absorb recoil energy, reduce recoil forces, or both. In some embodiments, a first buffer spring is aft of the bolt assembly and a second buffer spring is forward of the first buffer spring, forward of the carrier assembly, or a combination thereof. In some embodiments, a buffer adjusting nut adjusts preload of the second buffer spring, contacts the second buffer spring, or both. In particular embodiments, a buffer weight is located between the first buffer spring and the carrier assembly or the second buffer spring, the first buffer spring is longer than the second buffer spring, the first buffer spring is less stiff than the second buffer spring, the first buffer spring and the second buffer spring have a common axis, or a combination thereof.

What is claimed is: 
     
         1 . A firearm comprising:
 a bolt assembly;   a first buffer spring aft of the bolt assembly; and   a second buffer spring between the bolt assembly and the first buffer spring.   
     
     
         2 . The firearm of  claim 1  further comprising a buffer adjusting nut that adjusts preload of the second buffer spring. 
     
     
         3 . The firearm of  claim 2  wherein the first buffer spring is longer than the second buffer spring. 
     
     
         4 . The firearm of  claim 2  wherein the buffer adjusting nut is aft of the second buffer spring. 
     
     
         5 . The firearm of  claim 4  wherein the first buffer spring and the second buffer spring have a common axis. 
     
     
         6 . The firearm of  claim 1  further comprising a buffer weight located between the first buffer spring and the second buffer spring. 
     
     
         7 . The firearm of  claim 1  wherein the second buffer spring acts to reduce peak recoil force produced by the firearm. 
     
     
         8 . The firearm of  claim 1  wherein the second buffer spring acts to absorb recoil energy produced by the firearm. 
     
     
         9 . A firearm comprising:
 a bolt assembly;   a carrier assembly;   a first buffer spring aft of the carrier assembly; and   a second buffer spring between the bolt assembly and the carrier assembly.   
     
     
         10 . The firearm of  claim 9  further comprising a buffer adjusting nut. 
     
     
         11 . The firearm of  claim 10  wherein the buffer adjusting nut adjusts preload of the second buffer spring. 
     
     
         12 . The firearm of  claim 10  wherein the buffer adjusting nut contacts the second buffer spring. 
     
     
         13 . The firearm of  claim 10  wherein the buffer adjusting nut is aft of the second buffer spring. 
     
     
         14 . The firearm of  claim 9  further comprising a buffer weight located between the first buffer spring and the carrier assembly. 
     
     
         15 . The firearm of  claim 9  wherein the first buffer spring is longer than the second buffer spring. 
     
     
         16 . The firearm of  claim 9  wherein the first buffer spring and the second buffer spring have a common axis. 
     
     
         17 . The firearm of  claim 9  wherein the second buffer spring acts to reduce peak recoil force produced by the firearm. 
     
     
         18 . The firearm of  claim 9  wherein the second buffer spring acts to absorb recoil energy produced by the firearm. 
     
     
         19 . A buffer system for a firearm, the firearm comprising a bolt assembly and a carrier assembly, the buffer system comprising a buffer spring and a buffer adjusting nut, wherein the buffer adjusting nut adjusts preload of the buffer spring. 
     
     
         20 . The buffer system of  claim 19  further comprising a buffer weight and wherein the buffer adjusting nut contacts the buffer spring.