Can a slingshot reach a muzzle velocity of 200

No, the initial velocity (8mm bead) of the slingshot shot by an ordinary player is between 80~100m/s. After a period of practice through a reasonable configuration and mastery of certain skills coupled with a certain amount of power, you can increase the initial speed (8mm beads) to more than 100-120.

Slingshot , which became popular in the seventies and eighties. Slingshot is a cold weapon or game tool. Slingshot is generally by the bow frame, leather band, leather pocket three parts, generally made of tree branches, was "Ya" shape, on the two ends of the leather band, the leather band in the middle of the band to tie a package of projectiles on the leather block. The power of the slingshot depends on the tension of the leather band and the rebound speed of the leather band, the greater the tension of the leather band can match the heavier projectile, the faster the rebound speed of the leather band can provide to the projectile a greater initial velocity, the heavier the projectile, the higher the initial velocity of the greater the power. Slingshots can be categorized by their launch mechanism as either a slingshot with a bow blade or a slingshot with a leather strap. There are the most primitive bow-type slingshots and crossbows.