Constructing a circle from Half Circles

[man321]

Morning Everyone,
I am trying to construct a circle from two half circles on Opposite sides on the same Cylinderical barrel, I have made the half circles at exactly the same Location in Z. But no matter what i do , construction always fails, Its a Long Barrel , and i can't use a Star Probe or any thing else, we have done this in MM4 and it is as simple as recalling a Buffer in MM4.
Anyone ?

[tking]

CIR1 =FEAT/CIRCLE,RECT,IN,LEAST_SQR
THEO/0,0,-10.5,0,0,1,10
ACTL/0,0,-10.5,0,0,1,10
CONSTR/CIRCLE,BF,cir1.HIT[1],cir1.HIT[2],Cir1.HIT[3],Cir2.HIT[1],Cir2.HIT[2],Cir2.HIT[3],,
OUTLIER_REMOVAL/OFF,3
FILTER/OFF,UPR=0

TK