Last week manufacturer Dead Air Silencers announced ATF had changed its interpretations of the use and replacement of 'wipes' in silencers by their owners. Previously, industry had relied upon the Bardwell ATF opinion letter (http://www.titleii.com/bardwell/atf_letter66.txt) in which ATF explicitly states:
“In regard to the two parts in your cited example, we consider a
baffle to be a silencer, but a wipe, which is usually nothing more
than a rubber or plastic disc with a hole in it, is generally not
considered to be a silencer. Thus an individual owner could
replace a wipe.”
ATF informed Dead Air it no longer shares the opinion of the Bardwell letter, and asked the silencer manufacturer to immediately cease its unrestricted disribution of wipes. Consequently Dead Air immediately discontinued sales of what were disposable accessory wipes for their products. Dead Air announced they were in the process of developing longer-lasting inserts which even if considered part of the silencer would allow these designs to continue functioning.
We can only speculate why ATF has changed its interpretation of their earlier opinion letter, but it's possible they are preparing to restrict what they see as the next threat to proliferation: home manufacturing of firearms, particularly using 3D printers. It is a felony to manufacture a silencer at home prior to receiving an ATF-issued Form 1 Tax Stamp.
Arsenal Attorneys are concerned not only by the decision to regulate wipes as “suppressor parts” per se, but also with the inconsistency in policy that leaves the public vulnerable to swift and arbitrary changes to the rules.