Bushnell Custom 3x7 scopes with the BDC
I have several Bushnell Custom 3x7 scopes with the BDC. Most have the W1 dial for 50-200yrds. One has the W2 dial for 50-175 yds. I have seen a scope with a Z1 dial but could not see the range markings. I also have read that the three dials were for the 22lr std velocity, 22lr high velocity, and 22 mag. So what I need to know is which dial is which?