First pistol build 556 7.5” Rainier barrel with standard .063” gas port. All Aero Precision parts F/A BCG, Maxim CQB brace with proprietary 3 oz buffer.

What size gas port is best?  Sooooo many contradictory posts like, a .090 port is needed, one guy said .063 worked great with a 3 oz buffer.  Rainier recommends an H3 5 oz.

The Maxim buffers are $75 -$85 each so don’t want to just play around or over bore the port if needed.

Maybe I should convert to a 300BO if ammo is available.  
Thanks.

Edit. No suppressors in RI. ??

Does it run?

BCG coming on Sunday.  Just don’t want to build something that is temperamental.  Almost picked up a 10” barrel but if Springfield and ATI can make a 7” work then there is hope for me.
Wanted to see what you guys were running for port size and buffer weight.