1745 two strands of slingshot hit the turtledove stomach can be under?

According to personal arm length, cut the leather band, 1745 tied short, you pull not full, you can change the 2040

1842 four strands, it can be. 8 of the beads can be under the turtledove, two strands of the 2050

7mm beads can be under the pheasants, mainly to see what you hit the place.