Rolling Thunder responds:

I know this question has been asked many times but my story is...
I need to install about 200 sf of the top-nailed (older style, not the
tong & groove type) red oak hardwood floor. We were thinking to use
just hammers to do that, but it took us 2 days to install 50 sf in the
kitchen, with nail head yet to be sunk. So we decide to get a nail gun
for the rest of the job. Now the wood strip is 2" wide and 5/16" thick
oak, should I use 18 gauge brad nailer with 1" nail? Or should I go
for a 16 gauge finish nailer with 1" nail?
Thanks in advance,

There is a specialized nailer for wood floors. You hit it with a
hammer and the nail is driven into the edge of the hardwood flooring.
You can likely rent one.

AFAIK, those floor nailers work ONLY with t&g, which the OP said he did not
have.

Personally, I'd go for the thicker nail at least 1-1/2" long.

Charlie Self
"Give me golf clubs, fresh air and a beautiful partner, and you can keep the
clubs and the fresh air." Jack Benny