I was tuning my new sting. Set up is 7 1/4" brace, black moon riser, border hex 5 ws, new spaghetti secure button soft spring(cuz I can not spell the company name of the type of my head) and my new bcy-x string. As per last thread (those that gave me input might remember) I was at the end of my prior plunger as far as tension goes. It was all the way out and as a lefty, arrows will just barely making it to center, most hitting slight right. SO still shooting gold tip 600s with 125 and 100 grain tips and cheetah 650s with 125 grain tips. The curiostiy I came across is the gold tips tune better, dead on center after a little plunger play. The cheetah even though "650" spine and 125 grains tips still hitting stiff (right) by about 4 inches when compared to the stiffer 600 spine gold tips. Any input or insight? And my gold tips seem to group together no matter if 100 grain or 125 grain tip. I should them randomly so I do not know which tip is on arrow to do like a blind test which grain tip shoots better, but really find no big difference. This has baffled me, my stiffer 600 spine arrows shooting weaker than my 650 spine cheetah 3Ds.