A Gas bleed is a firearm component used for various purposes.
Bolt action riflesEdit
A gas bleed has been used on various bolt action rifles to prevent ruptured cartridges. First originated on the Remington Lee 1879 and 1882/1885 models (and possibly 1871 Beaumont rifles) but mainstream on Mauser rifles.
A gas bleed is found on gas operated firearms, usually a small hole on the barrel/gas block that is used to push back a gas piston to unlock the bolt.