for giggles i threw it together without a gasket (currently double gasketed) and it was .0125....but there also was no undesireable tight spots on the squish band due to the pop up... looked like the pop up was about .050+ from the edge of the band all the way around, at least at the spots i checked the squish with solder....
Did you do a compression test?
If you can get the squish down that low without a gasket why would you not want to use the 066 piston with one gasket and you could make the squish right and take care of the freeport?
Not at the .0125 squish.... i do my squish checks with no rings in, as it makes putting the jug on multiple times way easier, and eliminates the drag of the rings that likely would have masked the piston bottoming out on the case.
Because i am still new to building saws and dont need every last ounce of ommph out of it? If i need more oomph i have a MMWS jug on my ms661
theres some oomph for ya...Also.... you make it seem like freeport is a bad thing.... 
bottom line is, i only have a half tank thru this saw and its already got more balls than my woods ported 044....the 044 is fully broken in and about .025 squish, while the 460 is .050 squish and unseated rings.... why chase theoretical gains that could be losses in the end both time and money wise when i have a working combo?
