A couple weeks ago I bought a Leapers 1x30 tactical dot sight for my Marlin rifle. It's been crazy hot the past month, but the weather was cool enough today for me to spend some time outside without bursting into flame. At first I couldn't even hit the target, which makes zeroing the scope nearly impossible, so I had to move in to about 15 yards from the target to figure out just which way the adjust the scope. I finally got it close enough, then moved back to 40 yards to do the final adjustments. It took about 50 rounds to get it zeroed in properly. The results are much, much better than my first attempt with the iron sights.
I spent about $2.70 worth of ammo today.
This is why you should always inspect your ammo before loading.