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ICD-10-CM 2027 diagnosis code

W33.1Accidental rifle, shotgun and larger firearm malfunction

Not billable — use a more specific codeRequires 7th character

W33.1 is a header code, so it can't be reported by itself. Choose one of the 5 more specific codes beneath it and add the required 7th character.

Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data

About W33.1

W33.1 is the ICD-10-CM diagnosis code for accidental rifle, shotgun and larger firearm malfunction. It belongs to category W33 (accidental rifle, shotgun and larger firearm discharge and malfunction), block W20-W49 (exposure to inanimate mechanical forces) and chapter 20 (external causes of morbidity). It is a header code, so it can't be reported by itself; one of its 5 subcodes must be used instead.

Within W33 (accidental rifle, shotgun and larger firearm discharge and malfunction), W33.1 is specifically for accidental rifle, shotgun and larger firearm malfunction. Related codes cover discharge (W33.0).

Codes in this range require a 7th character: A for initial encounter, D for subsequent encounter and S for sequela. Use placeholder "X" characters to fill any empty positions before the 7th character.

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

7th character

The appropriate 7th character is to be added to each code from category W33

  • Ainitial encounter
  • Dsubsequent encounter
  • Ssequela

Coding notes

Applicable toConditions and synonyms classified to this code
  • Injury due to explosion of rifle, shotgun and larger firearm (parts)
  • Injury due to malfunction of mechanism or component of rifle, shotgun and larger firearm
  • Injury due to piercing, cutting, crushing or pinching due to (by) slide trigger mechanism, scope or other gun part
  • Injury due to recoil of rifle, shotgun and larger firearm
  • Powder burn from rifle, shotgun and larger firearm

Notes that apply from higher levels

Instructions written at a parent level also apply to W33.1.

› From W33 Accidental rifle, shotgun and larger firearm discharge and malfunction
Includes
  • rifle, shotgun and larger firearm discharge and malfunction NOS
Excludes1
  • accidental airgun discharge and malfunction (W34.010, W34.110)
  • accidental BB gun discharge and malfunction (W34.010, W34.110)
  • accidental handgun discharge and malfunction (W32.-)
  • accidental pellet gun discharge and malfunction (W34.010, W34.110)
  • assault by rifle, shotgun and larger firearm discharge (X94)
  • firearm discharge involving legal intervention (Y35.0-)
  • firearm discharge involving military or war operations (Y36.4-)
  • intentional self-harm by rifle, shotgun and larger firearm discharge (X73)

Broader instructions also apply from W20-W49 Exposure to inanimate mechanical forces and Chapter 20: External causes of morbidity.

Codes whose notes reference W33.1

Code history

  1. 2016
  2. 2017
  3. 2018
  4. 2019
  5. 2020
  6. 2021
  7. 2022
  8. 2023
  9. 2024
  10. 2025
  11. 2026
  12. 2027
  • FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
  • No changes since FY2016.

Common questions about W33.1

Is W33.1 billable?

No. W33.1 is a header code. Report one of its more specific subcodes instead.