most guns use 6mm bbs
-they are very small pellets
they also have 6 mm paintball for airsoft guns-
-they are the same size as regular 6mm, but they make a paint splat when they hit your target.
-dont use in shotguns, AEGs, gas pistols or electric pistols, only use them in spring pistols, they ruin any other king of gun
but ive seen some airsoft guns use 50 caliber
-they are wayyyy larger than regular 6mm bbs, and are more expensive
paintballs are 68 caliber
-paintballs are very large, cant be fired out of airsoft guns, the barrels are to small, and have liquid in them so people/ Refs can tell when you get hit
ps: these paint balls have nothing to do with airsoft
hope this helps
thanks for asking
sincerely~~~~~~~~~~~~~~~~~~~~~~~~
RYry
also there are different weights , .12 gram, use in not so good guns, or opistols
.20 gram use in AEGs & in gas & spring rifles & pistols
.23 gram use in snipers or high fps AEGs
.25 gram use in snipers or high fps AEGs
.28 gram use in high powered snipers
.33 gram use in high powered snipers
thats all of the bbs that would usually use, people usuall dont use .33 or .28
but the heavier the bb the more accurate it goes, but if its too heavy it would just drop, and if its to light it would curve up!
you must also know that the lighter the bb, the higher the velocity but itsless accurate.