"Readily Converted":
The Undefined Middle Ground in Massachusetts Firearms Law

MGL Chapter 140, Section 121 defines a firearm to include listed weapon types that are designed to or may readily be converted to expel a shot or bullet. It also includes frames, receivers, and unfinished frames or receivers, while excluding antique firearms and permanently inoperable firearms.^[1]

Change from the Earlier Definition

Chapter 135 replaced language focused on whether a shot or bullet could be discharged with the present "designed to or may readily be converted" formulation.^[2] Earlier Massachusetts operability cases interpreted the former text. Their holdings must be applied cautiously to the revised definition.

What Remains Unspecified

Section 121 does not supply a general factor test for how much time, skill, equipment, parts, or expense makes conversion "readily" achievable. It also does not define "permanently inoperable" in general terms. Other definitions in the same section use related language for particular categories, but they do not necessarily resolve every firearm-definition question.

Federal Law Is Not a Substitute

Federal firearms law also uses conversion concepts, and federal cases may be informative. They do not automatically establish the meaning of the Massachusetts statute. State and federal definitions, exceptions, and enforcement contexts must be analyzed separately.

Practical Effect

A missing or damaged component does not by itself establish that an item falls outside the Massachusetts definition. The item's design, present condition, available parts, and work needed to restore function may matter. No single example can establish a universal rule for other items.

Bottom Line

Treat a formerly functional or incomplete firearm as a fact-specific legal question unless it clearly falls within a statutory exclusion. For possession, transfer, registration, or serialization decisions involving a disabled or incomplete item, obtain qualified legal guidance.