Hand feeding Rat Pups

Question
Hi there!
I am dealing with 6 rat pups that were born yesterday. I woke up this morning to a mama that had passed away, I assume when she was giving birth. She had managed to clean the sacs off of the babies, and they are very much alive.  I have been doing some reading and the popular concensus is human soy milk, 5% of body weight every two hours, wiping bottoms to stimulate waste production, and massage after each feeding to encourage circulation.
Now, my problem is, what gadget am I supposed to use to feed them with? I have plunger-type syringes that go down to .1 ml, and I'm estimating that the babies are 5 grams in weight. Without a gram scale, I can't be sure. Is there a rough estimate scale that I can go by, possibly according to age? I was planning on starting with .3 ml and trying to guess from there as they grow, if I manage to keep them alive.
Any suggestions and guidelines you can offer would be very much appreciated, and how long can these guys go without eating before I need to consider euthanasia so they don't die of slow starvation?

Pam

Answer
I applaud you for your efforts, but its next to impossible to care for pups this young on your own.  Not that it doesnt work, but its hard work and heartbreaking as well since the chance of survival is very very low under 14 days of age.

Here is the best info going on how to care for orphaned pups even though you have a good idea on how to do it, this may help you find what your looking for:

http://www.ratfanclub.org/orphans.html