I ordered a G&P M4 from Evike last week and am still waiting for it to arrive. I have a pack of 10,000 Black Ops High Quality .20g biodegradable BB's at the house. These are polished and supposedly decent BB's. Will these BB's be ok to use with the G&P? My brother-in-law's KWA says in the manual to only use .23g BB's. I just don't want to screw up my gun.