Blowback firearms use the expanding gas impinging on the cartridge itself to push the <e1>bolt</e1> of the <e2>firearm</e2> rearward.
Blowback firearms use the
Blowback firearms use the expanding gas impinging on the cartridge itself to push the bolt of the firearm rearward.
<triplet> bolt <subject> firearm <object> Component-Whole(e1,e2)