When pressing 'e' on another player's turret, you take ownership of that turret (and ammo), and I believe all damage done by it is credited to the new owner. The original owner may still pack and re-deploy the turret.
Pressing 'e' on your own turret does not add ammo. The only way to add ammo is to pack up and re-deploy, at which point the turret is loaded with up to the default amount (if you have it available).
Somehow by spamming 'e' it's possible to fully take ownership and pack up another player's turret, though I haven't been able to reproduce this.
When pressing 'e' on another player's turret, you take ownership of that turret (and ammo), and I believe all damage done by it is credited to the new owner. The original owner may still pack and re-deploy the turret.
Pressing 'e' on your own turret does not add ammo. The only way to add ammo is to pack up and re-deploy, at which point the turret is loaded with up to the default amount (if you have it available).
Somehow by spamming 'e' it's possible to fully take ownership and pack up another player's turret, though I haven't been able to reproduce this.