Depends on the shafts. Ash is notorious, like hickory, for being hard to straighten and keep straight. But good shafts will straighten well and when sealed, stay straight. I have found that heated shafts tend to stay straighter. Seal them well,and eyeball them before your shooting session. They are tough, durable, and have enough weight to them to make any target, stolid or sentient, sit up and take notice.
Their performance in the hunting field makes them worth the effort.
Any wooden shaft in poor condition, or with excessive runout or "noodliness" is better off in the kindling pile. I have gotten wonderfully straight, tapered shafts from Ted Fry at Raptor Archery.
Killdeer