ATF open letter: repairing and changing the caliber of registered silencers

In an August 28, 2026 open letter, ATF says a registered complete silencer may be repaired or have its caliber changed without a new NFA “making” when the work does not destroy or alter its serialized frame or receiver, change required markings, or create a new firearm. The letter discusses replacement parts and warns that altering the serialized component may trigger different requirements. This guidance addresses modifications to registered silencers; ATF’s later October 9 letter separately addresses its enforcement policy for certain $0-tax NFA items. Read both official letters before relying on either policy.

Source: ATF firearms open letters