Guys, I've notice that the 1.25m standalone head shield is not using up any of its ablative. I got two probes enroute to Eve. The first one has the 1.25m heat shield and hits the atmosphere for an aerocapture at ~6000 m/s with a pe of ~56 Km and a Max g-load of ~4.0 Gs. Mechjeb says that I should lose ~1700 m/s of delta v. Like I said, the heat shield burns up and explodes without using any ablative at all. The second probe has the 2.5m head shield and uses its ~100 units of its 1000. The probe survives no problem and its going deeper in the atmosphere. Its traveling at ~ the same speed, max g-load of 7.0 Gs, and Mechjeb predicts its losing ~2300 m/s of delta v. Is my first probe blowing up because the heat shield is not working or am I exceeding its thermal capacity?