This is how I have done multiple pieces using a shift.
You set a variable for how many pieces you want.
Create a parts counter and then a looping statement.

Here is an example

#525=5(NUMBER OF PCS PER BAR)
G10L2P0Z0(RESETS G53 SHIFT)
#526=0(COUNTER RESET)
WHILE[#526LT#525]DO1
(G53 SHIFTS Z IN FOR EACH PART)
G10L2P0Z[#526*.873]
;
;
;
;
;
#526=#526+1(PARTS COUNTER)
M01
END1(LOOP BACK TO THE WHILE STATEMENT)
;
;
;
M30
%

This example will run 5 pieces shifting .873" for each part