What is sometimes refered to as 440 is usually just
440a, or 440b which are less desirable for knives than
440c. If you choose to use 440c, you should plan to do
all of your drilling and filing, and most of your grinding prior
to heat treat.
Unless you have experience heat treating, You should plan to
send your blades out to someone...perhaps Paul Bos..for heat treat.
You could also try to get together with someone for some instruction
in HT, as well as planning the order of the steps you'll use.
So.....is 440c forgiving..? Not very......If you're learning on your own. I'd
suggest starting with a non-stainless....perhaps 1080, or 5160.