aimming
Hi Sebastion,
I just happened across your thread and thought I'd see if I could help. The most important thing is as Anderson and Doug said-practice, practice and more practice. I see you're shooting an OMER 100cm gun. If it didn't come that way I would recommend using monofilament for your shooting line, also I put two full wraps for the shooting line. Using a line reel is a personal choice and it's what ever you're comfortable w/. Personally I use one.
A couple of things to check are the flopper and how much the end is bent up. Make sure the flopper lies completely flat on the shaft, also you don't want the tip of the flopper bent up too much also. Either one of these things will affect the flight of your shaft.
One thing you didn't mention is if your gun was shooting consistantly in any one direction during your miss's, i.e. low, left, right,ect.
As for aimming, like Anderson mentioned it becomes very instinctual after awhile. At first I would practice on targets arranged in the water. The soft foam that comes in computer boxes will work. I would cut a fish shape about the size of the average fish you are most likely to encounter. I would draw the kill zones to use as an aimming point. I believe Anderson has one on one of the other threads to look at. Tie it to a length of line to a weight so it floats mid water. Start fairly close, maybe a couple of gun lengths away. Hold the gun straight out w/ the barrel about eye level. Look down the barrel at the target. You will see the point of the shaft and the target in the same image. If the gun shoots fairly straight then you can judge left/right by just moving the gun in the direction to intersect the target. Up/down aimming is a little trickier. Depending on distance you may hold the point over, dead on, or even under your target. Keep practicing at your known distance until you are hitting the kill zone at least 90% of the time. In a sheltered area or friends pool it shouldn't take long. Once you have done this for awhile you will notice that you don't see the end of your shaft anymore, you just point your gun and it becomes an extention of your arm. You are learning your weapon and your body remembers it.
Another thing mentioned before,GET CLOSE! Learn to develope your stalking skills and patience. Don't rush your shot, It's better not to shoot than to shoot and make a bad hit and the fish rips off. This is a waste. It does happen sometimes but it should be the exception not the rule. Learn about the fish you are going to hunt. Their habits and behavior. A good rule of thumb I heard once is "don't shoot until you can clearly see their eye", when you can do this they're within range. I hope some of this will help you, please write if you have any other questions. Take care.
Jay