AOW - Any weapon restricted by a ban which is NOT the assault weapon ban
ATF - Bureau of Alcohol, Tobacco and Firearms
ATT - Alcohol and Tobacco Tax Division of the IRS, the pre-68 administrators of the NFA
AW - Assault Weapon
AWB - Assault Weapon Ban
BOB - Bug Out Bag - a survivalist's grab bag, kept stocked at all times (or else it isn't a BOB, just a fast packing job)
BOV - Bug Out Vehicle - a vehicle, usually an off-road vehicle, meant to traverse treacherous or blocked roads after SHTF.
BFSC - Basic Firearms Safety Card (a CA-specific certification, replaced by the HSC)
C&R - curio and relic
CFR - Code of Federal Regulations
COE - Certificate of Eligibility (a CA-specific certification)
DD - destructive device
DEWAT - De-activated war trophy
DOJ - Department Of Justice, usually for the state in question
FET - federal excise tax
FFL - federal firearms license
GCA - Gun Control Act
HSC - Handgun Safety Card (a CA-specific certification which replaced the BFSC)
LE - Law Enforcment
LEO - Law Enforcement Officer
LEGR - Law Enforcement Gun Release, a California-specific form which must be filled out before taking possession of a firearm siezed for evidence by LE.
NFA - National Firearms Act
PC - Penal Code, an abbreviation brought up whenever citing sections of law.
SBR - Short Barreled Rifle
SHTF - Stuff Hits The Fan. An abbreviation for any event which suspends the rule of law and order. Can be short-term (natural disaster, etc), or long-term (national collapse, etc).
SOT - special (occupational) taxpayer
TEOTWAWKI = The end of the world as we know it. Semi-permanent state of SHTF. Mad Max, etc.
U.S.C. - United States Code