no
As long as the owner's manual doesn't prohibit it.
Yes: A Remington 870 shotgun with a modified choke will shoot any commercial shotgun slug.
Yes
Yes, but would be better if you put in an improved cylinder choke.
no slugs should on be shot thru a improved cylinder shotgun. if you shoot thru any other choke it can cause the barrel to split
Can you shoot a standard slug threw a modified and or improved?
Yes, it is, but make sure you shoot foster style slugs. They are easier to force (swage) through the choke, and are designed for smoothbore shotguns. I like the Remington managed recoil slugs. A 1 oz. slug coming out at around 1250 fps is nothing to sneeze at, and they're very comfortable to shoot. If bears are your concern, however, I might go with something with a higher velocity.
A rifled slug- yes.
"Choke" refers to the amount that the barrel is constricted at the muzzle (located at the end of the shotgun barrel). The more constricted the bore opening is, the narrower and denser the pattern of shot which can be thrown. Several degrees of choke are commonly available, including full, improved-modified, modified, improved-cylinder and cylinder bore. Full choke barrels are made for long range shooting because they make the shot pattern denser at greater distances. Improved modified chokes fall between the full choke and the modified choke and are sometimes used in trapshooting. Modified chokes are midway between the full choke and the improved cylinder choke. Improved cylinder and cylinder bore or skeet chokes have little constriction and give the greatest spread (most open pattern) when shot is fired at close range. A slug may be fired through a choke so long as the slug can fit. If the choke is to small at best the choke threads will strip and at worst the barrel will split down the middle killing or maiming you. When in doubt ask the dealer.
because the choke is actually slightly smaller in diameter than the barre, for tightening the grouping of shot shells. A slug will cause major problems.
yes you can shoot rifled slugs through smooth bore barell, or use rifled choke for sabots. the sa08 takes the same choke as mossberg...win, etc.