I have had a Bushmaster A-3 shorty since January, but have only recently been able to shoot it.  I have two problems with regards to zeroing this rifle.  Keep in mind I am "U.S. Army trained" on the old A-1 sights.
1. ELEVATION. Being that this is a shorty the sight adjustment only goes to 600 meters, and there is no clicks lower than the 300 meter setting. Click by click, low to high it goes like this.
6/3, 0, Z, 0, 0, 0, 4, 0, 0, 0, 0, 0, 0, 0, 5, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 6/3.
Now for the question.  The manual says to rotate the elevation knob one click up. That would be the blank click inbetween the 6/3 and Z.  Given that the "Z" most likely stands for ZERO I thought that this may be a misprint.  Should I use the first click or set the elevation to "Z"?
2. DISTANCE.  There are not many places to shoot a rifle around me so I joined a rifle club which is about 45 minutes away.  The problem is the short rifle range only has 50 yard, 50 meter and 100 yard target holders making it impossible for me to zero at the recommended 25 yard mark.  The range master will not allow shooting at any distances other than the prescribed distances listed above.  Is there any way to battle sight zero my shorty at these distances.
Thanks in advance for your help.[thinking]
Ed

Forest,
Great instruction, I can't thank you enough.  About the yards/meters thing; it's been almost 9 years since I left active duty.  Memory fades with age.  Thanks again.
Ed