Screws and holes should be degreased with a solvent prior to use. Only a small amount is needed, usually one drop or less. Install screw immediately, do not over tighten and let set for at least 15 minutes before use. Small sight screws can easily be stripped or the head wrung off with excessive tightening. Snug is what you want.
Chinese screws are softer than typical American screws, so be careful.
Parts secured with this can be removed with common hand tools as long as the screw head is in good condition. Do not use on buggered up screws heads, or the will be even harder to remove. Most Chinese gun screws are standard metric threads, and Home Depot, or Industrial suppliers are a good place to look for replacements if needed. Scrapped electric or electronic products of all types can also yield a variety of free metric screws. Red is the strongest version.