Reduced Power Hammer Springs
SierraPapa reduced power hammer springs are manufactured in the USA from high grade spring steel. The new hammer springs are offered in two weights: light and medium. The light-weight spring provides the lowest trigger pull weight and it has been tested with complete reliability, using standard ammunition, in our test rifles. Theoretically there exists ammunition with "harder" primers. Our medium-weight trigger is an option for those who value ignition reliability with all possible ammunition types or who simply prefer a more positive trigger action in a combat carbine.
The reduced power hammer springs should only be used with our stainless steel hammer modification. Installing the reduced power hammer springs with the original CX4 plastic hammer may result in unreliable firing pin operation. The lighter weight of this spring causes it to be relatively more susceptible to the influence of each part of your CX4 when measuring trigger pull weight.
For best overall results the reduced power hammer spring should be installed concurrently with our trigger and hammer upgrades.
Price of hammer/trigger/spring upgrade kit: $186.50*
Shipping charge: $10.50* USPS Priority Mail
*A credit card processing fee of 3% applies to all credit card transactions. Payment by check, money order, or cash allows us to waive processing fees and keep our prices lower.