I have two sites (1) http://lifeinsurancequotescheap.com (2) http://uk-lifeinsurance.net. My site (1) was on 2nd position of the 1st page of the Google for my keyword "cheap life insurance quotes". Then i put 301 redirect in my site (2) and suddenly my site (1) was out off the SERP. Then i have removed 301 but my site is not re-gaining previous position why?
maybe because your keywords are not useful for your site. Or maybe your website was already sandbox. You can double check each pages of your site using cache:"then your site" to update if your site was crawl by google.
Bascially, when you redirect a domain to another one, Google takes almost 1 or more months to pass juice of the redirected domain to new one.., within this time, there will be a drop in Site and SERP too. If the redirection has done after 2months, still you are facing the same problem then the issue might be: The strategy you are following treats Google as a fishy one., because google certain parameters before transferring all the juice of this domain to another.., let me know if you need any more info on this.