301 Redirection and Loosing Rank in Google?@!#

[xjones]

Hi there:

I'm the webmaster for several sites. With the last Google update my sites (which were doing great before FL update) came within the top ten positions again in Google for my main keywords.

But, we decided to move all the sites under one URL. I did that mapping the sites with the 301 redirection.

I noticed that the site I didn't redirect lose rank (went from position #10 to #27 but at least is still there.

The other sites which I redirected are gone at least they are not in the 150.

Isn't that true that when you move your sites the wright way to handle it is with the 301?

You can see my sites:

The one which is still within Google, my main keyword is blood pressure monitors and the URL is:
http://www.blood-pressure-monitors-n...e-monitors.com

One example of a site a redirected with 301 is for heart rate monitors, old address was: http://www.heart-rate-monitors-n-hea...e-monitors.com

My new address is: http://www.jpimall.com/heartratemonitors

Main keyword is: heart rate monitors

By now you probaly realize why I change the site to the new adress instead of using the long old URL.

Any advice? Any ideas/comments?

Thank you for your time and advice,
Have a great day :0}