bigger is better, or should I say heavier is better with a slingshot. Out to 20 yards any muzzleloading ball 50 cal or larger will be fine. The bb sized stuff won't have enough butt to get the job done. You need something that will cause enough blunt force trauma to kill a small animal. Just like a bow, a slingshot will shoot one weight projectile more accuratly than another. Find the weight your slingshot likes and shoot that. Practice alot, and shoot instinctive. Shoot it just like a traditional style bow, hold it the same way everytime and pull it to the same anchor point on your face with every shot.20-25 yards is the max range for most slingshots.

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