Yes chokes are designed to tighten shot patterns.
You can use a sabot in any shotgun, as long as the barrel is not choked. If you have screw in chokes, you will want to use ONLY the Cylinder or CYL choke. Otherwise, you will need to look on the barrel to see what it is choked in. If you do not have screw chokes, unless it says CYLINDER or SLUG, it is probably choked. (It may say Improved, IM, Modified, Full, etc)
In states that do not allow the use of a high-power rifle to hunt deer, you may be able to use a shotgun loaded with buckshot or slugs.
Depends entirely on your intended end use.
Remington 870 pump loaded with "OO" buckshot or rifled slug
Depends on the use, and how YOUR shotgun patterns. For deer (some areas do not allow slugs or rifles, so buckshot it is) I am partial to 00 Buckshot. Larger pellets retain more energy, give better penetration.
Slug barrel
Assuming your shotgun has two triggers, you can fire either first. If you have one trigger, the order of fire can vary massively...use a gauge to check the bore on your gun, If you don't have one just use a coin and see how far it will go down the front of the barrel, or make a target out of cardboard to see which barrel is the more open barrel, by patterning the barrels. once you know which barrel is the the more open choke, you are ready to determine which barrel you want to shoot first, and as a quail hunter on the rise you will usually shoot the barrel with the more open choke first, saving the tighter choked barrel , as the game gets farther away. Source: shotgunworld.com
Miroku is simply a brand name, like Browning or Winchester. The correct size SHOTSHELL (proper term, not bullet) will be marked on the barrel, such as 12 guage, 2 3/4 inch, or 20 g, 3 inch, etc). The specific shell loading you want will depend on the use of the shotgun- buckshot or slugs for larger game, birdshot for small game.
I have no personal experience with this. What follows is information from a reputable local gun dealer. Rifled barrels are designed primarily for use with sabot slugs. Buckshot will not harm a rifled barrel because in the barrel, the plastic wadding holding the shot together will be the only portion of the projectile(s) in contact with the barrel. Firing rifled lead slugs will lead to difficult (nearly impossible) to clean out accumulations of lead in the barrel & negate the rifling because the rifling of the slug & the rifling of the barrel will not match up.
It will be marked on the barrel.
Deer slugs are the shotgun shells to use when deer hunting.
The Short answer is yes. Even in a 410 gauge shotgun with a full choke. Remember that a "410" is 41 caliber or .41 inches in diameter. oo buckshot is only about .32 inches in diameter. The same is true for shooting slugs in a shotgun. There is no safety issue involved. You will notice that there is no warning on the packaging of the ammunition. In our litigious times you can be sure that if there was a problem there would be a warning printed on the box.