A barrel with a full choke.
Either a full choke,or extra full choke shotgun barrel.
yes
the barrel is constricted at the end to make the pattern of shot flow density wider or tighter. Usually from cylinder up to full choke
It is possible to fire a shotgun without a choke, but it is highly not reccomended, and they don't cost that much If you select a barrel with no choke (cylinder) it will cause the pattern to be looser than for a barrel of a shotgun that has a tighter choke. The extreme is "full choke" which keeps a tight pattern out to the effective range. Full choke is typically used for waterfowl. A shotgun that is pressed into double duty (shot for small game and slugs for big game) would work well to have modified choke. Slugs have to be designed to fire through a full choke without blowing the barrel but you will certainly shorten the life of the barrel by firing slugs through a choked barrel. If you can afford an extra barrel, then use a cylinder (no choke) for slugs. Remington and other shotgun manufacturers have interchangeable choke tubes (see link) that allow you to screw in the appropriate choke for your quarry.
The Choke of a shotgun is the amount of barrel restriction at the muzzle end which affects the shot pattern. A full choke will keep the spray pattern of the pellets closer together farther out than if the barrel was not restricted at the muzzle. If there is no restriction at the muzzle, the choke is said to be cylinder choke or cylinder bore.
A shotgun barrel with a cylinder bore choke.
The choke is a way of narrowing the barrel. It is designed to keep the shot in a tighter pattern. A full choke is supposed to increase the effective range of the weapon.
If you mean a choke bored barrel, it designates the amount of constriction a shotgun barrel has.
They came in various barrel lengths and choke combinations. If it is not marked on the side of the barrel, you will have to pattern the shotgun to determine the choke
Being a double barrel has no bearing on what the choke COULD be. While MOST are full/ modified. it could be any, or none. Shotgun ChokeYardageShotgun Choke Restriction Diameter difference between bore and shotgun chokeCylinder< 200Skeet22.5.005 of an inchImproved Cylinder25.010Light Modified30.015Modified32.5.020Improved Modified35.025Light Full37.5.030Full40 or More.035Extra Full40 or More.040
There is an excellent article at the link below to explain the choke process for shotguns.
Best guess: You have a shotgun manufactured in Croatia. "Pun" means "Full" in Croatian. "Pola" means "Half". You would have something like 70% constriction in the Pun barrel and 55 to 60% constriction in the Pola barrel.