The MICV program continued on and in 1972 a new request for proposals was issued which was won by FMC and they began construction of the XM723 prototype which was completed in 1973 .
The MICV program continued on and , in 1972 , a new request for proposals was issued . 
 This was won by FMC , who began construction of the XM723 prototype , which was completed in 1973 .