Starting March 17, 2014, veterans who have a VA compensation rating of 100% permanent and total (P&T) may receive expedited processing of applications for Social Security disability benefits.

What do I need to know about the VA and Social Security programs?

Both Social Security and VA pay disability benefits. However, their programs, processes, and criteria for receiving benefits are very different.

A VA compensation rating of 100% Permanent and Total does not guarantee that you will receive Social Security disability benefits. To be approved for Social Security benefits, you must meet Social Security’s definition of "disability." We consider you disabled under Social Security rules if:
•You cannot do work that you did before;
•We decide that you cannot adjust to other work because of your medical
condition(s); and
•Your disability has lasted or is expected to last for at least one year or to result in death.

If you receive VA compensation, this will not affect your Social Security benefits.

http://www.socialsecurity.gov/pgm/disability-pt.htm

Sounds good on paper- the permanent and total part is harder to get than SSDI. I wonder what % of vets that are 100% VA disabled are actually P&T? less than 5% I would imagine.

I am rated at 100% UI by the VA and permanently disabled by Social Security. I have had both since 2007. I had to stop working due to my disabilities in Feb 2005. I was maxed at 60% by the VA until I started receiving SS Dis. in 2007, now I get both.