Does the amount of times dogs lock when breeding mean that is how many puppies they will have?

No, there is no relevancy as to how many times a dog "locks" equaling the amount of puppies. You do need to watch those dates that the dogs lock though, because it changes your due dates.

The best time to breed is once the bitch goes into actual heat, is actually bleeding, not just showing the signs. Then we allow the male and female to hook once a day for three days consecutively. This way we know that the breeding has taken place, because one day may not have taken where as another day it may have. Doing this only once a day also ensures that the male isn't exhausted and has strong sperm, and the female isn't exhausted. Then we calculate each of those 3 days out as the possible due dates. We never take them beyond those 3 days. There is more to it than just what I mentioned, but I am trying to stick to your question without giving information overload.