Blank cartridge device and developing appropriate self-loading firearm

The invention relates to a blank cartridge device (10) for use in a self-loading firearm, with a barrel (12) which extends from a cartridge chamber (14) to a mouth (16), with a mouth-side collecting device (20) for collecting a projectile, wherein the barrel (12) having a first run portion (22), which adjoins the chamber (14) and has an adapted to the caliber of the projectile first cross-section (32), and wherein the run second run section (24 ), which adjoins the first run section (22) and has a enlarged (in comparison with the first cross-section 32) the second cross-section (36).