Hello guys, is it possible to determine your PF without a chrono? I have ammo kasi for the match this weekend, but I'm not sure kung papasa cuz I changed the recipe and different din yung reloader. My current recipe is 4.7gr of VV N320, OAL of 1.17. My old load was around 4.6gr VV N20 with unknown OAL. I clocked at exactly 170pf. I added 1 gr. to be on the safe side. Does a change in OAL significantly change the velocity of the bullet? BTW, 180gr gamit ko na heads.