Bedding a new aeg

[MasterGouken]

I have a brand new G&P SR-15 URX and have installed a madbull tightbore and ultimate hop unit. The gearbox is standard G&P. I also have 10 brand new G&P 130 round midcaps.
What is the best way of bedding in the aeg and mags (bearing in mind i don't have a garden to run a few thousand rounds through it) and what should i do maintenance wise before skirmishing it?
I tried running a mag through it using .2 bb's and it would feed one or two bb's then it would stop feeding and one would just roll out of the barrel

*title should read "bedding in a new aeg*