The challenge factor is ten feet. Many scopes do not focus at such a short distance. But then, at ten feet your target can be a bit blurry and you will likely still nail it.
The second factor could be parallax error. This is where the plane of the image of the rattler and the reticle are not the same across all distances. Some scopes have a wheel to adjust the parallax across a variety of distances, but many do not adjust below 5 meters. However, it is likely the error will be quite small anyway.
The last part is reticle selection. You will need a scope which has dots (MOA or MIL), to support "holdover" or "holdunder" to compensate for the distance. A free program, such as Hawke Sports Optic's "Chairgun Pro", will allow you to determine what is the best zeroing distance for your scope/rings/airgun combination to achieve your goals. The first step will be for you to know the velocity and type of pellet. Then how much the rings lift the center of the scope above the center of the bore. Key those into the chairgun pro software. Then key in how much maximum height error you can tolerate (such as plus or minus 1/2 inch). Then key in with what you might want for ideal gun zeroing distance, such as 25 meter. Look at how it projects the amount of vertical error over your distance, and you can use your reticle "dots" to have the right holdover/holdunder for that distance. You can also just use clicks on your turret (provided your scope is repeatable, many scopes under $400 aren't as repeatable as most people would hope).
The picture below shows a run I did. It is plus and minus 1/2 inch from 16 to 56 meters, for a Benjamin Bulldog, but it gives a typical example of what you would see. If you look at the chart, I would require 2.5 inches of holdover at ten feet. It would require 10.25 inches of holdover at 100 yards.