The problem with all " tracers" is that they don't weigh the same as the other bullets that are not tracers, so they actually shoot to a different POI than regular bullets. We have all see the TV shows that picture tracers being fired from machine guns, either on the ground, or from fighter airplanes. Every fifth round was a tracer. Up close, no problem, but at 500 yds, and beyond, the tracers have either burned out, or are hitting lower than the other bullets.
Many people have tried to make tracers with Round Ball over the years. You can drill holes in the balls, with a drill press, and try to put some compound in it that will ignite. The question will be, will it ignite reliably, how long a fire will it give you, is the ammo even legal to use in your state?, and what will that burning compound do to the POI vs the POA? If the group widens to an unacceptable level, you have learned nothing.
It might be better, when sighting in a gun with a new ball, or load, to clamp a scope on it, even if that means useing hose clamps you would buy for your car's radiator hoses. They will hold the scope base on well enough for this limited kind of range use, and let you see the target. Once you have a good load, that shoot good groups, you can remove the scope, and zero the iron sights on a clear bright sunny day.
Shooters who are getting older eyes, like us, do a variety of different things to improve their vision. They switch to an aperature sight, and put a plastic glowing front site on the gun. Or, they use a merit site that attaches to their glasses, and has a changeable aperture to allow you to open or close the hole to the conditions you find in the field. I just heard of a man who pasted a small washer-shaped disc to the lens of his glasses to help his eyes focus better. By all means, consider getting shooting glasses, which move the focal point of the lens from the low center, where we look when reading, and often when looking straight ahead with our chins up, to the upper quadrant hear the nose, where we look through our glasses when shooting a rifle or shotgun. I bought glasses like this when I became serious out Trap shooting 20 years ago. If you can get your glasses prescription from your optician, you can order glasses from a few specialists- I found my guy from an ad in a Shotgun Sports magazine- that do this kind of work. Some of them attend the big Skeet and Trap and Sporting Clays shoots around the county, in a small truck where they can take measurements, and even fill orders for some of the more common type lens. I suspect one or more of these guys may appear at Camp Perry Ohio for the National Rifle Matches, too. I have not seen them at Friendship, however. If you are interest in shooting glass, PM me and I will give you the name of the guy who made my glasses.