wrote:

Phil,

I think the nails you are using are probably the "concret" variety
which are not suitable for what you are doing. Go to
http://www.tremontnail.com/ for a look see. I have used a variety of
their nails for several projects and am happy with the results. Also,
in order to avoid splitting the long side of the nail should be
parallel with the grain. Predrilling may be necessary for nails over
1.5".

Ed

Yes, they are concrete nails, but they're what I had on hand.
According to tremontnail.com, the prices look about the same for
hard-cut masonry nails that you can get at the Borg. I think I'll try
again, turning the nail 90 degrees and drilling a smaller pilot hole.
I don't mind buying nails, but why buy when I already have? Is there
something in particular that makes hard-cuts unsuitable?

-Phil Crow