Ho-3 cannon

{{short description|20 mm autocannon}}

{{Use British English|date=April 2017}}

{{Infobox weapon

|name=Ho-3 cannon

| image= Praboemoelih Sergeant. G.H. Smeets van het K.N.I.L. (Gadja Merah) en 2 man van , Bestanddeelnr 407-5-6 (cropped).jpg

| image_size = 300

|caption= Two dismounted Ho-3 cannons without the drum magazines. Note the ammunition belt.

|origin = Empire of Japan

|type= Aircraft autocannon

|is_ranged=yes

|is_bladed=

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|is_UK=yes

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|used_by= Imperial Japanese Army Air Service
Imperial Japanese Navy Air Service

|wars=World War II

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|weight={{convert|45|kg|lb|abbr=on}}

|length={{convert| 1749|mm|in|abbr=on}}

|part_length={{convert|1194|mm|in|abbr=on}}

|width=

|height=

|crew=

|cartridge=20x125mm (127)

|caliber={{convert|20|mm|in|abbr=on}}

|action=Short recoil-operated

|rate= 300-400 rounds/min

|velocity={{convert|830|m/s|abbr=on}}

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|feed= 60-round drum magazine

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}}

Ho-3 was a Japanese autocannon used during World War II. It was a drum-fed improvement of the magazine-fed Ho-1 cannon, itself derived from the Type 97 antitank rifle. It was used by the Kawasaki Ki-45KAIc heavy fighter of the Imperial Japanese Army Air Force.Gustin & Williams, p. 183