Fully understanding that energy is the square of velocity times mass, this is the lightest bullet I offer for use in an AR-10 and/or AR-15. This bullet is made with a pure copper jacket and a hybrid core consisting of 99.9% lead and 0.1% polymer (inside the base of the bullet) to achieve a weight reduction of 12.5% from it's older, 200 grain brother yet keeping the 200's outer dimensions. Built to stand up to the rigors of auto-loading with sturdy construction yet yield impressive expansion at typical .375 SOCOM velocities. You can expect delivery by the end of the month following the month purchased in though I try to deliver much earlier. When inventory is exhausted, back orders are taken and filled in the order they were received. I hope to post pictures soon!