I recieved a Field Grade Article 15 (which is Non-judicial punishment)
while in the military for a positvie urynalisis.  However I finished
my time in service with two combat tours and achieved the rank of
Sergeant and recieved an Honorable Dishcarge.  After this Art. 15 I
was able to not only buy a hand gun in my home state but also was
registered as a concealed weopons holder, but I was denied the
purchase of a rifle in the state I was stationed in.  Abviously there
is some kind of public or criminal record on file of this somewhere. 
What kind of offense and record would this be and how will it affect
me in the civilian world in regards to getting jobs?  (a federal or
state job even?)

It seems like you are referring to two different states:  your home
state that allowed you buy and carry a handgun; and the state in which
you were stationed.
IF this is so, the names of the states would be important to find an answer.

Here are two sites on article 15.  The first states clearly that it
does not establish a criminal record.  The second one, from the Air
Force, explains in detail the retention of art. 15 records and their
possible use, but this seems restricted to the military, federal
govt., and special instances relating to persons in health care.

http://www.reserve-nationalguard.com/general/article15.html
http://www.defenselink.mil/privacy/notices/usaf/F051AFJAF.html

Perhaps with the name of the state that denied purchase of a rifle, a
Researcher could indicate what factors could result in this.