Testing and Evaluation: Spring kit for CMMG .22 Bolt Carrier Group

I expressed interest in a set of springs that a local fellow posted online and he was generous enough to send me a set to test and evaluate. The springs are made for the CMMG .22 Bolt Carrier Group and will work with either conversion or dedicated versions.






Inside the package are the following:

  • stiffer recoil spring
  • softer firing pin spring
  • stiffer extractor spring

Supposedly these springs improve performance of the CMMG .22 AR kit.

Please stay tuned for updates as I will do some testing on units that have shown the following symptoms.


Lower receiver using a Timney drop-in AR trigger:

Problem: Light primer strikes

Test: softer firing pin spring

Lower receiver with factory 2 stage trigger

Problem: Hammer follows the bolt to the home position during rapid-fire. Unable to shoot further unless the user racks the charging handle. Chambered round is not fired.

Test: stiffer recoil spring, stiffer extractor spring.


Thank you Mr. Hernandez

Please stay tuned for an update.


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