It is hard to say 30 pt but I would definitely start with 145.It is a good idea to keep a variety of weights on hand.You can get some test kits from 3R.I also keep some 5 grain weight washers on hand to fine tune with when I get close.You can add up to three of those before running out of threads.I only use them for tuning or sometimes practice arrows as I like the rear shoulder of the point to seat against the insert,for strength,on my hunting arrows.Anyway,if it is slightly stiff,145 probably would work but be ready to add a little more if you need to.