On Wed, 14 Apr 2010 06:28:43 -0500, Lloyd E. Sponenburgh wrote:
"DoN. Nichols" ... [wrote]:

At first glance, they looked like drywall screws, but examining one
showed that instead of having a sharp spiral point, they had a drill
bit point, so they would drill through the metal and then thread in --
going into pre-drilled and countersunk holes in the sides of the new
top.

Yeah? (Um... they're called "self-drilling sheet metal screws". Any
ACE Hardware store will have them) G

But sheet metal screws don't look like drywall screws. More likely
they were Drill Point Drywall Screws, as shown at top of
http://www.aaronswoodscrews.com/DrywallScrews.htm and one screen
down in http://www.smithfast.com/drywallthreads.html. The latter
also shows (near the end, after the Trim Head Drywall Screws section)
Auger Point Deck Screws that look somewhat like drywall screws.
(With Type-17 point, as mentioned in the link Larry Jaques gave,
http://www.midstatesbolt.com/screwpoints.htm.)

--
jiw