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W33.1

W33.1Accidental rifle, shotgun and larger firearm malfunction

Non-billable headerICD-10-CM

W33.1 is a non-billable header ICD-10-CM code for accidental rifle, shotgun and larger firearm malfunction. It cannot be billed on its own: choose one of the more specific child codes below. This code also requires a 7th character before it is complete.

This code requires a 7th character

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

A
initial encounter
D
subsequent encounter
S
sequela

Inclusion terms

Alternative wordings a physician may use in the chart for this same 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

Other codes that can never be billed with W33.1

These codes carry an Excludes1 note pointing at W33.1. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading W33.1 alone.

  • W23Caught, crushed, jammed or pinched in or between objects
  • W32Accidental handgun discharge and malfunction

Risk adjustment

W33.1 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.

Code to one of these instead W33.1

5 child codes. Green means billable.

Related codes at this level

Codes that share W33. If W33.1 is not quite right, the correct code is usually one of these.

Questions about W33.1

Is W33.1 a billable ICD-10-CM code?
No. W33.1 is a non-billable header code. Code to a higher level of specificity using one of its child codes.
Where does W33.1 sit in the tabular list?
External causes of morbidity (V00-Y99), in the block Exposure to inanimate mechanical forces (W20-W49).
ICD-10-CMFY2026-Apr· effective April 1, 2026

Loaded directly from the CMS/NCHS ICD-10-CM public-domain release — see data sources and our editorial policy. If this page disagrees with the CMS tabular list, this page is wrong. Reference information for professional coders; not medical or billing advice.