We recommend shooting 50 rounds through your barrel, splitting this up enough to not overheat the barrel. Usually 25 round strings is okay to keep the barrel from getting too hot.
Then clean the barrel down to bare metal by removing all copper and carbon. We recommend using Bore Tech's Eliminator.
After cleaning the barrel shoot 50 more rounds through the barrel in 25 round strings to prevent overheating of the barrel.
Finally clean the barrel again to bare metal and your barrel is broken in. 

Yes, we only chamber our barrels tho as we can not guarantee the quality of other barrel makers.