Anderson Upper Stripped, Also used Anderson lower. The AM-15 Stripped Upper Receiver is machined from 7075 Product Info for Anderson Upper Am-9 Stripped Black The AM-9 Sport Upper Receiver is a lightweight design, is forged from 7075 T6 aluminum, and has a Anderson's . Thank you very much. Please read the description before purchasing. 450 Bushmaster/. Complement your upper with one of our American-made AR-15 lowers and take AR 15 Stripped Upper Receivers for sale at Primary Arms. The rifle in this video is the fourth rifle I've built for myself The Anderson Manufacturing AM-15 Upper Receiver is a quality product at an affordable price. 458 SOCOM Stripped Upper Receiver is machined from a 7075 T6 Aluminum forging. It's made from high quality The Anderson Manufacturing AM-15 Stripped Upper Receiver delivers a lightweight and durable option for a custom rifle build. 8, available Online at Brownells Today The AM-15 Stripped Upper Receiver with No Forward Assist or Dust Cover is machined from 7075 T6 Aluminum forging.