It doesn't matter. Most self defense takes place inside 7 meters. At that range shotgun loads have not had a chance to spread to any siginificant degree.
Not unless you have to change the choke tube.
They are for the choke wrench most likely. Choke markings are usually on the body of the tube.
Soak in diesel overnight to loosen dirt/debris, use choke key supplied with gun
Try want ads, gun shows, e-gunparts.com, gun shops
DO NOT ATTEMPT TO FIRE BUCKSHOT OUT OF A THREADED BARREL WITHOUT A CHOKE TUBE INSTALLED!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Danger, Danger, Danger
Choke tubes are round case-like devices that tighten the pattern of BBs as they leave the barrel of a gun. The tighter the pattern, the better its long-distance accuracy will be.
Try Mid West Gun Works.
From Mossberg's website:"Can I shoot slugs or buckshot through a "smoothbore" field barrel with Accu-Choke™ tubes? (500/505/535/9200/88/930 models) Yes, and with sabots or rifled slugs, the more "open" the choke tube, the better the accuracy ("Improved Cylinder" recommended.) The "full" or "modified" choke tubes are preferred for buckshot loads. Slugs, buckshot and steel shot loads are not recommended for use with an extra full "turkey tube" installed, due to the tube's tight constriction. Do not fire any load without a choke tube installed, doing so will damage the internal choke tube threads. "
Full choke.
criminals in most cases. Personal defense in others.
You can purchase a choke tube for a Smith & Wesson 3000 shotgun at various sporting goods stores, specialized gun shops, or online retailers such as Brownells, MidwayUSA, or Amazon. It's important to ensure the choke tube is compatible with your specific shotgun model. Additionally, checking manufacturer recommendations or forums dedicated to shotgun enthusiasts can provide guidance on the best options available.
Even in a situation where you shoot some one in self defense the police must take control of your gun. Receiving the gun back will depend on the full out come of the situation.