I have had 4 sets of limbs (go) on me since I started shooting crossbows. The first two were both on a Parker Buckbuster 175 and both times they were at full cock when the middle of the limbs snapped loose. I had an Excal Vortex come straight out of the box with a splinter about 3" long on the left limb. I snapped it off and shot the bow two full deer seasons before getting new limbs. The 4th was an Excal Matrix 330 that I bought used off the classifieds from George (Mainstreet) and I was the 4th or 5th owner. I removed the limbs one day and noticed a crack starting across the limb so I got new limbs for it. I figure it had probably been dryfired a few times before I bought it.