maybe 80 feet at 45 degrees
They will "fit" but they will not fire correctly, and will break when the bolt tries to push two of them at once.
no
it depends what type of marker you are using 99% percent of the time it will be .68 cal but you can find .43 and .50 cal markers.
Not recommended
Any round pipe can shoot darts that fit inside it. I would not use it as a dart gun however.
Almost every paintball gun out there is a .68 cal. so they should have em
No.
No
Yes, the standard .68 cal paintball marker can fire "pepper balls".The "pepper" that it fires is actually Capsaicin II (chili-pepper) More information can be found in the website link to the sources and related links(below).
No
No it will jam in the barrel.
No. Only shoot the caliber printed on the barrel.