plug and play my friend....setup your 20.....estimate yoru 30.....then shoot your 30.....get it dialed in, then match that gap from your 20/30, to your 30/40 if anything put that 40 just a tad farther than the 20/30 gap, and test your 40...and so forth....

My pins I'd estimate at 1/8" gap from 20/30,