1. Always ensure that the weapon is clean before firing subsonic rifle ammunition. A dirty bore creates a dangerous situation.
2. Always ensure that the previous projectile exited the bore before loading or firing the next round. If in doubt, stop and inspect the bore.
3. Always treat subsonic rifle ammunition and the weapons it is in with the same respect given any other ammunition and weapon. Just because it is quiet does not mean that it is not as dangerous as any other weapon system.
These instructions are necessary because subsonic rifle ammunition is not a "one size fits all" proposition due to variances in bore size and comparative smoothness or roughness, and because chamber dimensions are not all the same. While reasonable care is exercised in the production of this ammunition and it functions in most weapons satisfactorily, it is the end user's responsibility to ensure that his particular weapon works safely with this specialized ammunition.