Possible causes include, ammunition, magazine, spring,etc..
If it's doing it regularly, it may be an extractor problem.
See a gunsmith.
A gun recoils when fired due to the need to eject the casing and to recycle the pent up gas
Many types. First, muzzle loaders do not use cartridge casings. Only autoloading firearms automatically eject a fired casing. Revolvers, and lever action, bolt action, and pump action firearms require a specific action by the shooter to eject a fired casing, as do single shot and double barreled shotguns.
A shell, fired from a field-gun or a mortar.
On the ground, in a pocket, in a bucket, etc..
An expended shell casing is the empty metal container left behind after a bullet is fired from a gun. It holds the primer, gunpowder, and projectile before being shot. Shell casings are often collected at crime scenes as evidence to help identify the type of weapon used.
To help keep foreign matter (dirt) out of the action when the weapon is not firing.
When a gun fires, the primer and burning gunpowder eject residue. That residue is chemically like very few things OTHER than gunshot residue (GSR) If your clothes test positive for GSR, it is a pretty safe bet you were very close to a gun that was fired. It may or may not tell whether YOU fired the gun.
It means that the shell will eject on the left side not the right. Same way with rifles.
The gun does not always cycle. It also will not always eject the shell. These can both be potentially dangerous situations.
Its quite simple as that it ejects the shotgun shell out of the gun after it has been fired but this depends on the type. A double or single barrel shotgun would only eject the shells when u hit the release mechanism to reveal your side of the barrel then they eject out.On any other type shot gun where u load 8 or have a clip they generally fling out the side when re-cocked or if automatic they do this automatically. Hope i helped