Most types of suppressors have no appreciable effect on the ballistics of the rifle they may be attached to. The problem is that the bullet velocity must be subsonic. If it is supersonic the shock wave is quite audible and defeats the purpose of the supressor which can only suppress the sound of the escapng gas.
There was at least one type of now obsolete supressor in which the bullet after leaving the barrel muzzle passed through a pin hole in several successive rubber diaphragms. Since they actually contacted the bullet they tended to detract from accuracy.
