Barrel chart is down for upgrades and updating, i hope. It's probably gonna be a while since there's so many choices of barrels and paints.
Keep in mind that paintballs VARY FROM LOT TO LOT and as such, older paint may be swollen or out of round, which will lead to breaks/failure to feed. Buy fresh paint that's been sealed, and check each bag before you buy to make sure none have broken in transit or due to rough handling.
Also, make sure your barrel is correctly fitted to the paint size, or paint will get stuck(and break), or slide right out(low velocity & poor accuracy). Make sure your barrel is screwed in tightly to the breach of your paintball marker(also causing low velocity & breaks).
As originally posted by someone else, I just decided to save everybody some time. Barrel and paint chart for most barrels and paintballs on the market, including some discontinued barrels and paints.
Barrel Chart
Paint Chart