I have a have and have seen several WWII Gem, Red Cross and other discs but 
 the original poster, on another list, states that they are definitely "45" 
 blanks. 
 
I have a 7" lacquer disc blank with the "45" center hole so they were  
available. That may have been a likely format to use during the Korean  war era, 
since a "45" player would have been more universally available  than reel 
tape, or even a 78 turntable late in the decade. 
 
Of course during the 50's and 60's, there were many more alternate means  
available to "call home" than during WWII, but if one wanted to send a disc  
recording, the "45" format could make sense then.
 
Mike Csontos
 
 
In a message dated 11/18/2009 2:18:08 P.M. Eastern Standard Time,  
[log in to unmask] writes:

These  records were very widespread all over the country and in some of
the major  points of encampment around the world.  But there is one thing
that is  very important for Ms. Denman to know about them -- they are NOT
45s, they  are 78s.  There was no 45 speed until 1949.